# Patent

## Title
Module for “machine-to-machine” communications using public key infrastructure

## Abstract

Methods and systems are provided for efficient and secure “Machine-to-Machine” (M2M) between modules and servers. The module and server can utilize public key infrastructure (PKI) such as public keys to encrypt messages. The module and server can use private keys to generate digital signatures for datagrams sent and decrypt messages received. The module can internally derive pairs of private/public keys using cryptographic algorithms and a set of cryptographic parameters. The module can authenticate the submission of derived public keys. The module and server can mutually derive shared secret keys using the PKI keys. Data can be encrypted and decrypted using a set of cryptographic algorithms, the secret shared keys, and the set of cryptographic parameters. A module can send and receive sets of cryptographic parameters in order to flexibly and securely communicate with a variety of servers over time.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
The subject matter of this application is related to the subject matter of U.S. patent application Ser. No. 14/023,181, filed Sep. 10, 2013 in the name of John Nix, entitled “Power Management and Security for Wireless Modules in ‘Machine-to-Machine’ Communications,” which is hereby incorporated by reference in its entirety.
The subject matter of this application is also related to the subject matter of U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, entitled “Secure PKI Communications for ‘Machine-to-Machine’ Modules, including Key Derivation by Modules and Authenticating Public Keys,” which is hereby incorporated by reference in its entirety.
The subject matter of this application is also related to the subject matter of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, entitled “Systems and Methods for ‘Machine-to-Machine’ (M2M) Communications Between Modules, Servers, and an Application using Public Key Infrastructure (PKI),” which is hereby incorporated by reference in its entirety.
The subject matter of this application is also related to the subject matter of U.S. patent application Ser. No. 14/064,618, filed Oct. 28, 2013 in the name of John Nix, entitled “A Set of Servers for “Machine-to-Machine” Communications using Public Key Infrastructure,” which is hereby incorporated by reference in its entirety.
The subject matter of this application is also related to the subject matter of U.S. patent application Ser. No. 14/084,141, filed Nov. 19, 2013 in the name of John Nix, entitled “Key Derivation for a Module using an Embedded Universal Integrated Circuit Card,” which is hereby incorporated by reference in its entirety.
BACKGROUND
1. Technical Field
The present methods and systems relate to communications for a module, and more particularly, to methods and systems for supporting secure, efficient, and flexible communications using Internet Protocol networks, where a module for “machine-to-machine” communications can communicate with a set of servers.
2. Description of Related Art
The combination of “machine-to-machine” (M2M) communications and using low-cost sensors, Internet connections, and processors is a promising and growing field. Among many potential benefits, M2M technologies allow the remote monitoring and/or control of people, assets, or a location where manual monitoring is not economic, or costs can be significantly reduced by using automated monitoring as opposed to manual techniques. Prominent examples today include vending machines, automobiles, alarm systems, and remote sensors. Fast growing markets for M2M applications today include tracking devices for shipping containers or pallets, health applications such as, but not limited to, the remote monitoring of a person's glucose levels or heartbeat, monitoring of industrial equipment deployed in the field, and security systems. Many M2M applications leverage either wired Internet connections or wireless connections, and both types of connections continue to grow rapidly. M2M applications may also be referred to as “the Internet of things”.
M2M communications can provide remote control over actuators that may be connected to a M2M device, such as, but not limited to, turning on or off a power switch, locking or unlocking a door, adjusting a speed of a motor, or similar remote control. A decision to change or adjust an actuator associated with an M2M device can utilize one or a series of sensor measurements. An M2M device may also be referred to as a “wireless module” or also simply a module. As one example, if a building or room is too cold, then temperature can be reported to a central server by an M2M device and the server can instruct the M2M device to turn on a switch that activates heat or adjusts a thermostat. As the costs for computer and networking hardware continue to decline, together with the growing ease of obtaining either wired or wireless Internet access for small form-factor devices, the number of economically favorable applications for M2M communications grows.
Many M2M applications can leverage wireless networking technologies. Wireless technologies such as, but not limited to, wireless local area networks and wireless wide area networks have proliferated around the world over the past 15 years, and usage of these wireless networks is also expected to continue to grow. Wireless local area network (LAN) technologies include WiFi and wireless wide area network (WAN) technologies include 3rd Generation Partnership Project's (3GPP) 3rd Generation (3G) Universal Mobile Telecommunications System (UMTS) and 4th Generation (4G) Long-term Evolution (LTE), LTE Advanced, and the Institute of Electrical and Electronics Engineers' (IEEE) 802.16 standard, also known as WiMax. The use of wireless technologies with “machine-to-machine” communications creates new opportunities for the deployment of M2M modules in locations without fixed-wire Internet access, but also creates a significant new class of problems that need to be solved.
First, many wireless wide-area networking standards were designed and optimized for mobile phones, which may be continuously connected to the network during the day (i.e. non-sleeping hours for most subscribers while they may charge phones at night), in order to receive inbound phone calls and messages. In this case, the radio may be in an idle state but utilizing discontinuous reception, but the radio is still active and drawing power in order to receive and process incoming signaling from the network such as, but not limited to, a Public Land Mobile Network (PLMN). A need exists in the art to make wireless M2M communications efficient in order to conserve battery life and radio-frequency spectrum resources.
Since the packets transmitted and received by a wireless module will likely traverse the public Internet for many applications, a need exists in the art to (i) prevent eavesdropping at intermediate points along the path of packets transmitted and received, (ii) allow endpoints to verify the identity of the source of packets received. A need exists in the art for a wireless module and a monitoring server to leverage established public key infrastructure (PKI) techniques and algorithms. A need exists in the art for communication to be secured without requiring the established, but relatively processing, bandwidth, and energy intensive security protocols, such as, but not limited to, IPSec, Transport Layer Security (TLS), and Secure Socket Layer (SSL) between a module and a server. The establishment of theses links requires extra overhead in the form of packet handshakes and/or key exchanges at levels including the network and transport layer of the traditional Open Systems Interconnection (OSI) model.
M2M applications frequently require small, periodic messages sent between a wireless module and a monitoring server, where the wireless module sleeps between the messages. M2M applications may leverage wired modules as well which can also sleep between messages. During relatively long periods of sleep such as 30 minutes or more, the a wireless or wired network with intermediate firewalls will often tear down the network and/or transport layer connections, which means the wireless module would need to re-negotiate or reestablish the secure tunnels each time the wireless module wakes and seeks to send a relatively small message to a server. A need exists in the art for supporting established security protocols with an external application, without requiring them to be implemented on a module due to the relatively long periods of sleep and other complexities from inactivity in the module.
Next, a need exists in the art for the communication between a module and a monitoring server to be highly energy and bandwidth efficient in order to reduce energy consumption over the operating lifetime of a module. A limiting factor for a wireless module for M2M applications deployed or installed into the field is the lifetime of the battery of the wireless module. If the transmission techniques for the wireless module are not energy efficient, the system will require more frequent manual intervention for the replacement or recharging of batteries. The energy saving techniques for transmitting and receiving data should leverage established Internet protocols. For wired modules operating for years or decades, a significant cost will be the power consumed from land-line power.
Further, a need exists in the art for the secure, energy efficient communications that support Internet protocols to support intermediate firewalls that may exist along the path of packets sent and received by both a wireless module and a monitoring server. Without support for communication through an intermediate firewall, packets may be blocked by the firewall and the M2M application would not properly function in this case. Currently, there are dozens of manufacturers and form-factors of modules, and this diversity will continue to increase for the foreseeable future. By leveraging standards such as the Internet and PKI technologies, an efficient, secure, and highly scalable system of communicating could support the wide variety of modules.
In addition, the utilization of PM technologies in modules can increase security, but a number of technical challenges must be addressed. These challenges increase if a deployed module required updated private/public key pairs after operation begins. The typical paradigm of “swapping out a SIM card” (which also depend on a pre-shared secret key Ki embedded in the card) with mobile phones may not be applicable or cost effective with modules, where swapping out the SIM card could be burdensome. A need exists in the art to allow for a deployed module to securely and automatically begin using new private and public keys (i.e. without human intervention such as swapping out a SIM card). Newer PKI technologies may offer a wide variety of algorithms for ciphering with public keys, and a need exists in the art for the utilization of new public and private keys to support the wide variety of algorithms and possible parameters, even after a module has been installed. A need exists in the art for a scalable and secure method of associating a module identity with a module public key, when the module begins utilizing a new public key. A need exists in the art for a module to efficiently be able to utilize multiple public/private key pairs at the same time, such as with different service providers or different applications simultaneously. And other needs exist in the art as well, as the list recited above is not meant to be exhaustive but rather illustrative.
SUMMARY
Methods and systems are provided for secure and efficient communication using a module to communicate with a server and a mobile operator network. The module can support “Machine to Machine” (M2M) communications, also known as “the Internet of things”. The methods and systems contemplated herein can also support other applications as well, including mobile phone handsets connecting to a wireless network, where the wireless network can be associated with or the radio access portion of a mobile operator network. A module in the present invention can comprise a mobile phone such as a smartphone. An objective of the invention is to address the challenges noted above for securing the deployment of modules that can utilize an embedded universal integrated circuit card (eUICC) and/or also PM algorithms and keys. The methods and systems contemplated herein can reduce the need for manual intervention with a module in order to automatically and remotely utilize and update new or different keys in order to securely communicate with a network.
Exemplary embodiments may take the form of methods and systems for a module. The module and a server associated with an M2M service provider can include a set of cryptographic algorithms for use in sending and receiving data. The cryptographic algorithms can include asymmetric ciphering algorithms, symmetric ciphering algorithms, secure hash algorithms, digital signature algorithms, key pair generation algorithms, a key derivation function, and a random number generator. The module can utilize a set of cryptographic parameters with the set of cryptographic algorithms.
The module can utilize the set of cryptographic algorithms and the set of cryptographic parameters to securely generate or derive module private keys and module public keys. A module private key and module public key can be generated either (i) upon manufacturing, distribution, installation, or an initial use of the module, or (ii) at subsequent times after initial use such as when a new set of key pairs are required or are useful for continued operation of the module. A module private key that is loaded into a module by a manufacturer, distributor, technician, or end user can comprise an initial module private key, and a private key that is derived by a module after installation or distribution can comprise a derived module private key. After deriving the module public key and module private key, the module private key can be preferably recorded in a nonvolatile memory within the module.
A first embodiment can comprise a method for a module to securely and efficiently send sensor data to a server. The module can include a sensor for automatically collecting data regarding a monitored unit. The module can comprise a wireless module that connects to a wireless network, including a wireless WAN such as a public land mobile network (PLMN). The module and the network can use standards that include Internet Protocol (IP) at the network and transport layers of the open systems interconnection (OSI) stack. The module can record an initial module private key and a module identity in a non-volatile memory, and the initial module private key and module identity could be recorded by a module manufacturer, or the module identity could be recorded by a module manufacturer and a distributor or end user could record the initial module private key. An eUICC subscription manager could also provide the initial module private key. Upon connecting with a first network, the module can receive a set of cryptographic parameters using the initial module private key.
Continuing with this first exemplary embodiment, the module can derive a module private key and a module public key using the set of cryptographic parameters and the set of cryptographic algorithms. The module can send a message with the derived module public key and the module identity to a server and the module can authenticate the message using the initial module private key. A server could record or have access to an initial module public key associated with the initial module private key, and the server can use the initial module public key to authenticate the message sent by the module. In this manner of a module using the initial module private key and the server using the initial module public key, the module can authoritatively send the derived module public key, such that a fraudulent or otherwise unauthorized module could not feasibly submit a public key for the module with the module identity. After sending and authenticating the derived module public key, the module can send a sensor measurement with a module identity in a message to the server, and the message could contain a module encrypted data. The module can use the derived module private key to encrypt the module encrypted data. The server can use the received, authenticated module public key to decrypt the module encrypted data. The server can record or forward the sensor data, and the module can repeat the process of collecting sensor data and using the derived module private key to send the sensor data.
In another embodiment, the module may be deployed within a wireless network such as, but not limited to, a 4G LTE network, a LTE Advanced network, or a WiFi network, and the module may comprise a wireless module. After being installed next to a monitored unit, the wireless module can (i) wake from a sleep or dormant state, (ii) utilize a sensor to collect data associated with a monitored unit, (iii) connect to the wireless network using Internet Protocol standards, and (iv) send the sensor data to a server. During an active state, the module can use a UDP IP:port number to both send a message to the server and receive a response to the server. The message as a UDP datagram can be a UDP Lite datagram and with a checksum only applied to the packet header. A UDP Lite datagram with sensor data can include channel coding for the body of the datagram to mitigate the effect of bit errors. In this embodiment, the wireless network can preferably support the UDP Lite protocol.
In another embodiment, a module can use a first module private key and a server can use a first module public key to establish communication between the two nodes. The server can belong to a mobile network operator and be associated with a wireless network. The server can securely send the module a set of cryptographic parameters, where the set of cryptographic parameters includes values to define an equation for an elliptic curve. The values could comprise constants and variables such that the module can calculate an elliptic curve, and the elliptic curve can be different than standard, published curves. The set of cryptographic parameters could be sent from the server to the module in a server encrypted data, where the server encrypted data is decrypted by the module using any of (i) the first module private key, (ii) a symmetric key, and (iii) a shared secret key. The module can use the set of cryptographic parameters, a random number generator, and a key pair generation algorithm within a set of cryptographic algorithms in order to generate a new, second module key pair, which could comprise a second module public key and a second module private key. The module can securely and/or authoritatively send the second module public key to the server, where the steps to implement security for sending the second module public key can include using of the first module public key and/or the shared secret key.
In another embodiment, a module with a module identity can derive its own public and private keys after distribution of the module using a first set of cryptographic parameters. A module can send a message that includes a module identity, where the module identity can be verified using at least one of a module digital signature and a shared secret key. A set of servers can send the module with the module identity a second set of cryptographic parameters, which can be different than the first set of cryptographic parameters. Over time, the module can use at least a subset of the second set of cryptographic parameters to derive multiple pairs of module public and private keys. Over time, the module can (i) send a series of module public keys with the module identity and (ii) use a previous module public key in the series to verify and/or authenticate a message with a module public key sent by the module to the server.
These as well as other aspects and advantages will become apparent to those of ordinary skill in the art by reading the following detailed description, with reference where appropriate to the accompanying drawings.



BRIEF DESCRIPTION OF THE DRAWINGS
Various exemplary embodiments are described herein with reference to the following drawings, wherein like numerals denote like entities.
FIG. 1a is a graphical illustration of an exemplary system, where a server and a module connect using a wireless network, in accordance with exemplary embodiments;
FIG. 1b is a graphical illustration of hardware, firmware, and software components for a module, in accordance with exemplary embodiments;
FIG. 1c is a graphical illustration of components within a module, in accordance with exemplary embodiments;
FIG. 1d is a graphical illustration of components in a set of cryptographic algorithms, in accordance with exemplary embodiments;
FIG. 1e is a graphical illustration of an exemplary system, where a module and a server exchange a set of cryptographic parameters and a subset of the set of cryptographic parameters, in accordance with exemplary embodiments;
FIG. 1f is an illustration of a certificate that includes a PKI public key, where the key comprises an elliptic curve cryptography (ECC) key, in accordance with exemplary embodiments;
FIG. 2 is a graphical illustration of an exemplary system, where a module sends a message to a server, and where the module receives a response to the message, in accordance with exemplary embodiments;
FIG. 3 is a flow chart illustrating exemplary steps for a module to send sensor data to a server, in accordance with exemplary embodiments;
FIG. 4 a is a flow chart illustrating exemplary steps for a module to process a message, including encrypting sensor data and sending a digital signature, in accordance with exemplary embodiments;
FIG. 5a a is a flow chart illustrating exemplary steps for a module to process a response from the server, including verifying a server's identity and decrypting instructions, in accordance with exemplary embodiments;
FIG. 5b is a flow chart illustrating exemplary steps for a module to communicate with a server after deriving a public key and private key, in accordance with exemplary embodiments;
FIG. 5c is a simplified message flow diagram illustrating exemplary steps for a wireless module to detach from a wireless network, in accordance with exemplary embodiments;
FIG. 6 is a simplified message flow diagram illustrating an exemplary message sent by a module, and an exemplary response received by the module, in accordance with exemplary embodiments;
FIG. 7 is a flow chart illustrating exemplary steps for a module to derive a series of public keys and private keys, including sending and authenticating the derived public keys, in accordance with exemplary embodiments;
FIG. 8 is a simplified message flow diagram illustrating an exemplary message sent by a module, wherein the message includes a derived module public key, in accordance with exemplary embodiments;
FIG. 9a is a graphical illustration of public keys, private keys, and a key derivation algorithm, in accordance with exemplary embodiments;
FIG. 9b is a graphical illustration of deriving a symmetric key using public keys, private keys, and a key derivation algorithm, in accordance with exemplary embodiments; and,
FIG. 10 is a simplified message flow diagram illustrating an exemplary system with exemplary data transferred between a module and a set of servers, in accordance with exemplary embodiments.



DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION
FIG. 1a 
FIG. 1a is a graphical illustration of an exemplary system, where a server and a module connect over a wireless network, in accordance with exemplary embodiments. The system 100 includes a module 101 operating within a wireless network 102. System 100 can also include a module provider 109, an IP Network 107, and a M2M service provider 108, a certificate authority 118, and a monitored unit 119. M2M service provider 108 can include a server 105. For embodiments where the M2M service provider 108 comprises a mobile network operator, the mobile network operator could use 4G LTE and LTE Advanced networks, an server 105 could comprise a home subscriber server (HSS) or a mobility management entity (MME). System 100 is illustrated without specific packet transmissions between module 101 and M2M service provider 108. Examples of the communications and messages pertaining to the present invention will be illustrated in later Figures. As contemplated herein, machine-to-machine communications may comprise communication between a module 101 and a server 105, such that data can be transferred between the two with minimal manual intervention, although manual intervention can be required to set up system 100 and any occasional manual maintenance required. As contemplated herein, machine-to-machine communications may also be referred to as “the Internet of things” (IoT). Also note that module 101 may comprise a wireless module, such that module 101 can communicate with wireless network 102 using a radio and an antenna. A wireless or a wired configuration for module 101 can be utilized in the present invention.
If module 101 operates as a wireless module, module 101 and wireless network 102 can communicate using a base station 103. Module 101 and wireless network 102 can utilize a variety of wireless technologies to communicate, including WiFi, WiMax, a 2nd generation wireless wide area network (WAN) technology such as, but not limited to, General Packet Radio Services (GPRS) or Enhanced Data rates for GSM Evolution (EDGE), 3rd Generation Partnership Project (3GPP) technology such as, but not limited to, 3G, 4G LTE, or 4G LTE Advanced, and other examples exist as well. A wired module 101 can connect to the IP Network 107 via a wired connection such as, but not limited to, an Ethernet, a fiber optic, or a Universal Serial Bus (USB) connection (not shown).
Generally, the communication techniques described herein can be independent of the network technologies utilized at the physical and data-link layers, so long as the underlying network provides access to the IP Network 107 and supports Internet Protocols (IP). The IP Network 107 can be an IPv4 or an IPv6 packet-switched based network that utilizes standards derived from the Internet Engineering Task Force, such as, but not limited to, RFC 786 (User Datagram Protocol), RFC 793 (Transmission Control Protocol), and related protocols. The IP Network 107 can be the public Internet comprising globally routable IP addresses, or a private network that utilizes private IP addresses. IP Network 107 as illustrated in FIG. 1a could comprise the globally routable public Internet, or IP Network 107 could also be a private Internet that is (i) not globally routable and (ii) only accessible to authorized modules and servers. As one example of a private IP Network 107, IP Network 107 could use private IP addresses for nodes on the network, and in this case IP Network 107 could be referred to as an intranet or private network. Alternatively, IP Network 107 could be a private network layered on top of the publicly routable Internet via secured and encrypted connections. The specific numbers for IP addresses and port numbers shown in FIG. 1a and other figures are illustrative and any valid IP address or port number can be used, including an IPv4 and an IPv6 address. Server 105 within M2M service provider 108 can communicate with the module 101 using IP network 107, where IP network 107 can comprise a private network that utilizes Internet Protocol standards.
When operating in a wireless network configuration, module 101 can access the IP Network 107 via the wireless network 102. In the wireless network configuration, module 101 can be a wireless handset, a cellular phone, a smartphone, a tablet computer, a laptop, a computer with a radio, a tracking device, or a circuit board with a radio that accesses wireless network 102. Examples of wireless modules that utilize a wireless WAN such as, but not limited to, 2G and 3G networking technologies include the Motorola® G24-1 and Huawei® MC323. Example manufacturers of wireless modules in 2012 include Sierra Wireless® and Telit®. Example leading manufacturers of mobile phones in 2013 include Apple® and Samsung®. In a wired configuration (not shown), module 101 can be a computer, security camera, security monitoring device, networked controller, etc. A more detailed depiction of exemplary components of a module 101 is included in FIG. 1b and FIG. 1c below. Module 101 could also comprise a “point of presence” payment terminal, such that a sensor 101f (in FIG. 1b below) associated with module 101 could collect payment information such as, but not limited to, an account number from a credit card or similar payment card. Module 101 could communicate with the payment card via a magnetic reader or near-field wireless communications, and in this case the magnetic reader or antenna for near-field communications can function as a sensor. Module 101 could also operate as a “smartcard” such that an end user presents module 101 to merchants for payments.
Wireless network 102 may comprise either a wireless local area network (LAN) or a wireless WAN such as a public land mobile network (PLMN). Examples for technologies used in wireless LANs include an 802.11 WLAN, Bluetooth, or Zigbee among other possibilities. Module 101 operating in wireless mode could communicate with a base station 103 of a wireless network 102 using a radio and an antenna. Wireless network 102 could operate as a Mode II device according to FCC Memorandum Opinion and Order (FC-12-36) and related white space regulation documents. If module 101 supports IEEE 802.15.4, then wireless network 102 could be a Zigbee network, an ISA100.11a standards-based network, or a 6LoWPAN network as described by IETF RFC 4944. Other possibilities exist as well for the wireless technology utilized by a wireless network 102 and module 101, operating in a wireless mode, without departing from the scope of the present invention.
Module 101 can collect data regarding a monitored unit 119 and periodically report status to a M2M service provider 108 or a server 105. Examples of a monitored unit 119 can include a vending machine, an alarm system, an automobile or truck, a standard 40-foot or 20-foot shipping container, or industrial equipment such as, but not limited to, a transformer on an electrical grid or elevator in a building. Additional examples of a monitored unit 119 include can also include a pallet for shipping or receiving goods, an individual box of pharmaceuticals, a health monitoring device attached to a person such as, but not limited to, a pacemaker or glucose monitor, and a gate or door for opening and closing. Other examples exist as well without departing from the scope of the present invention. Module 101 can utilize a sensor to measure and collect data regarding a parameter of monitored unit 119 such as, but not limited to, temperature, physical location potentially including geographical coordinates from a Global Positioning System (GPS) receiver, radiation, humidity, surrounding light levels, surrounding RF signals, weight, vibration and/or shock, voltage, current, and/or similar measurements.
As illustrated in FIG. 1a, wireless network 102 may include a wireless network firewall 104 and M2M service provider 108 may include a server network firewall 124. These firewalls may be used to secure communication at the data link, network, transport, and/or application layers of communications using the IP Network 107. Firewalls 104 and 124 could perform network address translation (NAT) routing or operate as symmetric firewalls, and/or selectively filter packets received through IP Network 107 in order to secure system 100. The firewall functionality of firewalls 104 and 124 could be of many possible types, including a symmetric firewall, a network-layer firewall that filters inbound packets according to pre-determined rules, an application-layer firewall, or a NAT router, as examples. Firewalls 104 and 124 could also implement an IPSec tunnel between the two firewalls. Although a single firewall 104 and 124 is illustrated in wireless network 102 (or a wired network 102 or simply “network 102”) and with M2M service provider 108, respectively, firewall 104 and 124 may each comprise multiple firewalls that operate in conjunction and the combined operation may be considered a single firewall 104 and 124, respectively.
According to a preferred exemplary embodiment, module 101 may preferably record a module private key 112. As described in additional figures below, module 112 can generate a key pair comprising a module private key 112 and a module public key 111, where module private key 112 resides within module 101 and may not be shared or transmitted to other parties. Alternatively, the present invention also contemplates that module 101 does not derive its own module private key 112, and rather module private key 112 can be securely loaded or transmitted to module 101, and in this case the loaded module private key 112 can comprise an initial module private key 112b. Module 101 may also be associated with a module provider 109. Module provider 109 could be a manufacturer or distributor of module 101, or may also be the company that installs and services module 101 or associates module 101 with monitored unit 119. Module provider 109 can record a module public key 111 and a certificate 122 (illustrated below in FIG. 10 for module 101. Module public key 111 may be associated with a module public key identity 111a, which could be an identifier of module public key 111.
Either module provider 109 or M2M service provider 108 could function as a eUICC subscription manager 164, where an eUICC subscription manager 164 can manage the recording and secure distribution of eUICC profiles to a module 101. Other entities could operate as an eUICC subscription manager 164 as well. An eUICC subscription manager is described in ETSI TS 103 383 v12.1, entitled “Smart Cards; Embedded UICC; Requirements Specification,” which is herein incorporated by reference in its entirety. An eUICC subscription manager 164 can also use a server 105 and record private keys and public keys for the server/subscription manager operation. In embodiments, eUICC subscription manager 164 can use a module public key 111 (with asymmetric ciphering) or a symmetric key 127 (with symmetric ciphering) to cipher an eUICC profile (such as, but not limited to, a received eUICC profile 163a depicted and described in connection with FIG. 1c below), such that only module 101 with module private key 112 could reasonably decipher the eUICC profile. In this manner, the eUICC profile 163a can remain reasonably secured. The eUICC subscription manager 164 can use either symmetric ciphering 141b or asymmetric ciphering 141a to encrypt the eUICC profile 163a. The module public key 111 used by an eUICC subscription manager 164 can comprise an initial module public key 111b, where the initial module public key 111b can be derived outside module 101 and loaded into module 101. Or, the eUICC subscription manager 164 can use a module public key 111 derived by the module 101 (such that derived module public key 111 has been transferred to the eUICC subscription manager 164 in a secure and reliably manner).
In embodiments, a module 101 may utilize multiple module public keys 111 over the lifetime of module 101 (including multiple corresponding module private keys 112), and module public key identity 111a can be used to select and/or identify the correct module public key 111. Module public key identity 111a could be a string or sequence number uniquely associated with module public key 111 for a given module 101 (i.e. module public key identity 111a does not need to be globally unique). As illustrated in FIG. 1a, module public key identity 111a may preferably not be included in the string or number comprising module public key 111, but rather associated with the string or number comprising module public key 111, and in this case the two together (module public key identity 111a and the string or number for module public key 111) can refer to module public key 111 as contemplated herein. In addition, module 101 can record an initial module private key 112b and an initial module public key 111b. These initial keys can be different from a module private key 112 and a module public key 111 since the “initial” keys can be derived from an outside source and loaded into a module 101, and module private key 112 and module public key 111 can be derived by module 101.
The module public key 111 or initial module public key 111b can optionally be signed by a certificate authority 118 in order to confirm the identity of module 101 and/or the identity of module provider 109. Module provider 109 can also function as a certificate authority 118 for module 101. Thus, the validity of module public key 111, possibly recorded in a certificate 122 (illustrated in FIG. 10 in the form of a signature 123 could be checked with module provider 109, and the wireless module provider's 109 provider public key 120 could be checked against certificate authority 118. Other configurations for signing public keys and using certificates with public keys are possible as well without departing from the scope of the present invention.
Public keys and private keys as contemplated in the present invention, including module public key 111 and module private key 112 and additional keys described herein, may leverage established standards for Public Key Infrastructure (PKI). Public keys may be formatted according to the X.509 series of standards, such as, but not limited to, X.509 v3 certificates, and subsequent or future versions, and these keys may be considered cryptographic keys. The keys can support standards such as, but not limited to, the International Organization for Standardization (ISO) ISO/IEC 9594 series of standards (herein incorporated by reference) and the Internet Engineering Task Force (IETF) RFC 5280 titled “Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile” (herein incorporated by reference), including future updates to these standards.
Module public key 111 and module private key 112, as well as the other private and public keys described within the present invention, could be generated using standard software tools such as, but not limited to, Openssl, and other tools to generate public and private keys exist as well. Public and private keys as contemplated herein could be recorded in a file such as, but not limited to, a *.pem file (Privacy-enhanced Electronic Mail), a file formatted according to Basic Encoding Rules (BER), Canonical Encoding Rules (CER), or Distinguished Encoding Rules (DER), or as text or binary file. Other formats for public and private keys may be utilized as well, including proprietary formats, without departing from the scope of the present invention. As contemplated herein, a key may also comprise a public key, a private key, or a shared key including a secret shared key such as, but not limited to a symmetric key 127. A public key as contemplated herein may also be considered a certificate or a public certificate. A private key as contemplated herein may also be considered a secret key.
Server 105 can include a module database 105k. For embodiments where M2M service provider 108 comprises a mobile network operator, server 105 can operate as an HSS or MME in 4G LTE networks, including recording network access credentials such as identities, public keys, and symmetric keys for a plurality of modules 101 in a module database 105k. Server 105 could be a plurality of individual computers operating in a coordinated manner through a network in order to function as a server 105. Server 105 can include a server public key 114 and a server private key 105c. M2M service provider 108 can also include a network private key 165a and a network public key 165b. Additional details regarding the various public and private keys illustrated in FIG. 1a will be provided in Figures below.
Other configurations besides the one illustrated in FIG. 1a are possible as well. Wireless network 102 could be included in M2M service provider 108, and M2M service provider 108 could comprise a mobile network operator. In many common commercial relationships for the operation of mobile phone service in the United States in 2013, wireless network 102 could represent a portion of the radio access network used by a M2M service provider 108 as a mobile network operator. A mobile network operator could outsource the operation and maintenance of a radio access network, such as a wireless network 102, to 3rd parties. In this configuration, wireless network 102 could represent a network operated by a first company specializing in the operation of radio towers and BTS equipment. This first company could be contracted with the M2M service provider 108 as a mobile network operator in order to support mobile phone service or data services to modules 101.
In addition, server 105 could reside within wireless network 102 in a data center managed by wireless network 102. Wireless network 102 could also operate as a module provider 109. Although a single module 101, server 105, wireless network 102, and M2M service provider 108 are illustrated in FIG. 1a, system 100 could comprise a plurality of each of these elements. Module 101 could also record sensor data pertaining to a plurality of monitored units 119. Module 101 could be mobile, such as physically attached to a truck or a pallet, and module 101 could connect to a series of different wireless networks 102 or base stations 103 as module 101 moves geographically. Other configurations are possible as well for the elements illustrated in FIG. 1a without departing from the scope of the present invention.
FIG. 1b 
FIG. 1b is a graphical illustration of hardware, firmware, and software components for a module, in accordance with exemplary embodiments. FIG. 1b is illustrated to include many components that can be common within a module 101, and module 101 may also operate in a wireless configuration in order to connect with a wireless network 102. Module 101 may consist of multiple components in order to collect sensor data or control an actuator associated with a monitored unit 119. In a wireless configuration, the physical interface 101a of module 101 may support radio-frequency (RF) communications with networks including a wireless network 102 via standards such as, but not limited to, GSM, UMTS, mobile WiMax, CDMA, LTE, LTE Advanced, and/or other mobile-network technologies. In a wireless configuration, the physical interface 101a may also provide connectivity to local networks such as, but not limited to, 802.11 WLAN, Bluetooth, or Zigbee among other possibilities. In a wireless configuration, module 101 could use a physical interface 101a be connected with both a wireless WAN and wireless LAN simultaneously. In a wired configuration, the physical interface 101a can provide connectivity to a wired network such as, but not limited to, through an Ethernet connection or USB connection.
The physical interface 101a can include associated hardware to provide the connections such as, but not limited to, radio-frequency (RF) chipsets, a power amplifier, an antenna, cable connectors, etc., and additional exemplary details regarding these components are described below in FIG. 1c. Device driver 101g can communicate with the physical interfaces 101a, providing hardware access to higher-level functions on module 101. Device drivers 101g may also be embedded into hardware or combined with the physical interfaces. Module 101 may preferably include an operating system 101h to manage device drivers 101g and hardware resources within module 101. The operating systems described herein can also manage other resources such as, but not limited to, memory and may support multiple software programs operating on module 101 or server 105, respectively, at the same time. The operating system 101h can include Internet protocol stacks such as, but not limited to, a User Datagram Protocol (UDP) stack, Transmission Control Protocol (TCP) stack, a domain name system (DNS) stack, etc., and the operating system 101h may include timers and schedulers for managing the access of software to hardware resources. The operating system shown of 101h can be appropriate for a low-power device with limited memory and CPU resources (compared to a server 105). An example operating system 101h for module 101 includes Linux, Android® from Google®, Windows® Mobile, or Open AT® from Sierra Wireless®. Additional example operating systems 101h for module 101 include eCos, uC/OS, LiteOs, and Contiki, and other possibilities exist as well without departing from the scope of the present invention.
A module program 101i may be an application programmed in a language such as, but not limited to, C, C++, Java, and/or Python, and could provide functionality to support M2M applications such as, but not limited to, remote monitoring of sensors and remote activation of actuators. Module program 101i could also be a software routine, subroutine, linked library, or software module, according to one preferred embodiment. As contemplated herein, a module program 101i may be an application operating within a smartphone, such as, but not limited to, an iPhone® or Android®-based smartphone, and in this case module 101 could comprise the smartphone. The application functioning as a module program 101i could be downloaded from an “app store” associated with the smartphone. Module program 101i can include data reporting steps 101x, which can provide the functionality or CPU 101b instructions for collecting sensor data, sending messages to server 105, and receiving responses from server 105, as described in the present invention.
Many of the logical steps for operation of module 101 can be performed in software and hardware by various combinations of sensor 101f, actuator 101y, physical interface 101a, device driver 101g, operating system 101h, module program 101i, and data reporting steps 101x. When module 101 is described herein as performing various actions such as acquiring an IP address, connecting to the wireless network, monitoring a port, transmitting a packet, sending a message, receiving a response, or encrypting or signing data, specifying herein that module 101 performs an action can refer to software, hardware, and/or firmware operating within module 101 illustrated in FIG. 1b or FIG. 1c performing the action. Note that module 101 may also optionally include user interface 101j which may include one or more devices for receiving inputs and/or one or more devices for conveying outputs. User interfaces are known in the art and generally are simple for modules such as, but not limited to, a few LED lights or LCD display, and thus user interfaces are not described in detail here. User interface 101j could comprise a touch screen if module 101 operates as a smartphone or mobile phone. As illustrated in FIG. 1b, module 101 can optionally omit a user interface 101j, since no user input may be required for many M2M applications, although a user interface 101j could be included with module 101.
Module 101 may be a computing device that includes computer components for the purposes of collecting data from a sensor 101f or triggering an action by an actuator 101y. Module 101 may include a central processing unit (CPU) 101b, a random access memory (RAM) 101e, and a system bus 101d that couples various system components including the random access memory 101e to the processing unit 101b. The system bus 101d may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures including a data bus. Note that the computer components illustrated for the module 101 in FIG. 1b may be selected in order to minimize power consumption and thereby maximize battery life, if module 101 includes a battery and is not attached to external power. In addition, the computer components illustrated for the module 101 in FIG. 1b may also be selected in order to optimize the system for both long periods of sleep or idle states relative to active communications and also may be optimized for predominantly uplink (i.e. device to network) communications with small packets or messages. The computer components illustrated for the module 101 in FIG. 1b may also be general-purpose computing components, and specialized components are not required in order to utilize many of the embodiments contemplated herein.
Module 101 may include a read-only memory (ROM) 101c which can contain a boot loader program. Although ROM 101c is illustrated as “read-only memory”, ROM 101c could comprise long-term memory storage chipsets or physical units that are designed for writing once and reading many times. As contemplated within the present invention, a read-only address could comprise a ROM 101c memory address or another hardware address for read-only operations accessible via bus 101d. Changing data recorded in a ROM 101c can require a technician have physical access to module 101, such as, but not limited to, removing a cover or part of an enclosure, where the technician can subsequently connect equipment to a circuit board in module 101, including replacing ROM 101c. ROM 101c could also comprise a nonvolatile memory, such that data is stored within ROM 101c even if no electrical power is provided to ROM 101c. Although not depicted in FIG. 1b, but illustrated in FIG. 1c below, module 101 could also include a flash memory 101w. Module program 101i, data reporting steps 101x, operating system 101h, or device driver 101g could be stored in flash memory 101w within module 101 when the module is powered off. These components and/or instructions could be moved from a flash memory 101w (not shown in FIG. 1b but shown in FIG. 1c) into RAM 101e when the module is powered on. Note that ROM 101c could be optionally omitted or included in a memory unit within CPU 101b (not shown).
Although the exemplary environment described herein employs ROM 101c and RAM 101e, it should be appreciated by those skilled in the art that other types of computer readable media which can store data that is accessible by a module 101, such as, but not limited to, memory cards, subscriber identity module (SIM) cards, local miniaturized hard disks, and the like, may also be used in the exemplary operating environment without departing from the scope of the invention. The memory and associated hardware illustrated in FIG. 1b provide nonvolatile storage of computer-executable instructions, data structures, program modules, module program 101i, and other data for computer or module 101. Note the module 101 may include a physical data connection at the physical interface 101a such as, but not limited to, a miniaturized universal serial bus adapter 101v (illustrated in FIG. 1c), firewire, optical, or other another port. The computer executable instructions such as, but not limited to, module program 101i, data reporting steps 101x, operating system 101h, or device driver 101g can be initially loaded into memory such as, but not limited to, ROM 101c or RAM 101e through the physical interface 101a before module 101 is given to an end user, shipped by a manufacturer to a distribution channel, or installed by a technician. In addition, the computer executable instructions such as, but not limited to, module program 101i, data reporting steps 101x, operating system 101h or device driver 101g could be transferred wirelessly to module 101. In either case (wired or wireless transfer of computer executable instructions), the computer executable instructions such as module program 101i, data reporting steps 101x, operating system 101h, or device driver 101g could be stored remotely on a disk drive, solid state drive, or optical disk (external drives not shown).
A number of program modules may be stored in RAM 101e, ROM 101c, or possibly within CPU 101b, including an operating system 101h, device driver 101g, an http client (not shown), a DNS client, and related software. Further, the module program 101i and/or data reporting steps 101x can perform the various actions described in the present invention for the module 101 through instructions the module program 101i and/or data reporting steps 101x provide to the CPU 101b. A user may enter commands and information into module 101 through an optional user interface 101j, such as a keypad, keyboard (possibly miniaturized for a mobile phone form-factor), and a pointing device. Pointing devices may include a trackball, an electronic pen, or a touch screen. A user interface 101j illustrated in FIG. 1b can also comprise the description of a user interface 101j within U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, which is herein incorporated in its entirety.
The module 101, comprising a computer, may operate in a networked environment using logical connections to one or more remote computers, such as the server 105 illustrated in FIG. 1a. Server 105 can also function as a general purpose server to provide files, programs, disk storage, remote memory, and other resources to module 101 usually through a networked connection. Additional remote computers with which module 101 communicates may include another module 101 or mobile device, an M2M node within a capillary network, a personal computer, other servers, a client, a router, a network PC, a peer device, a base station 103, or other common network node. It will be appreciated that the network connections shown throughout the present invention are exemplary and other means of establishing a wireless or wired communications link may be used between mobile devices, computers, servers, corresponding nodes, and similar computers.
The module program 101i and data reporting steps 101x operating within module 101 illustrated in FIG. 1b can provide computer executable instructions to hardware such as CPU 101b through a system bus 101d in order for a module 101 to (i) collect data from a sensor 101f, (ii) change the state of an actuator 101y, and (iii) send or receive packets with a server 105, thus allowing server 105 to remotely monitor or control a monitored unit 119. The module program 101i and/or data reporting steps 101x can enable the module 101 to transmit or send data from sensor 101f or module 101 by recording data in memory such as RAM 101e, where the data can include sensor data, a destination IP:port number, a packet or packet header value, an encryption or ciphering algorithm and key, a digital signature algorithm and key, etc. The data recorded in RAM 101e can be subsequently read by the operating system 101h or the device driver 101g. The operating system 101h or the device driver 101g can write the data to a physical interface 101a using a system bus 101d in order to use a physical interface 101a to send data to a server 105 using the IP Network 107. Alternatively, the module program 101i and/or data reporting steps 101x can write the data directly to the physical interface 101a using the system bus 101d. 
The module program 101i and/or data reporting steps 101x, or operating system 101h can include steps to process the data recorded in memory such as, but not limited to, encrypting data, selecting a destination address, or encoding sensor data acquired by (i) a sensor 101f or (ii) through a physical interface 101a such as, but not limited to, a thermocouple, shock or vibration sensor, light sensor, or global positioning system (GPS) receiver, etc. The module 101 can use the physical interface 101a such as, but not limited to, a radio to transmit or send the data from a sensor to a base station 103. For those skilled in the art, other steps are possible as well for a module program 101i or operating system 101h to collect data from a sensor 101f and send the data in a packet without departing from the scope of the present invention.
Conversely, in order for module 101 to receive a packet or response from server 105, the physical interface 101a can use a radio to receive data from a base station 103. The received data can include information from a server 105 and may comprise a datagram, a source IP:port number, a packet or header value, an instruction for module 101, an acknowledgement to a packet that module 101 sent, a digital signature, and/or encrypted data. The operating system 101h or device driver 101g can use a system bus 101d and CPU 101b to record the received data in memory such as RAM 101e, and the module program 101i or operating system 101h may access the memory in order to process the received data and determine the next step for the module 101 after receiving the data. The steps within this paragraph may also describe the steps a module program 101i or data reporting steps 101x can perform in order to receive a packet or a response 209 below. For those skilled in the art, other steps are possible as well for a module program 101i, data reporting steps 101x, or module 101 to receive a packet or response from a server 105 within the scope of the present invention.
Moreover, those skilled in the art will appreciate that the present invention may be implemented in other computer system configurations, including hand-held devices, netbooks, portable computers, multiprocessor systems, microprocessor based or programmable consumer electronics, network personal computers, minicomputers, mainframe computers, and the like. The invention may also be practiced in distributed computing environments, where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices. In addition, the terms “mobile node”, “mobile station”, “mobile device”, “M2M module”, “M2M device”, “networked sensor”, “industrial controller”, or “user equipment” can be used to refer to module 101 or its functional capabilities of (i) collecting sensor data regarding a monitored unit 119, (ii) changing state of an actuator 101y associated with monitored unit 119, and/or (iii) communicating the data associated with a monitored unit 119 with a wireless network 102. The function of module 101 and sensor 101f could be integrated, and in this case module 101 could also be referred to as a “sensor”, “intelligent sensor”, or “networked sensor”. Further, the term “module” or “monitoring device” can be used to refer to the module program 101i when module program 101i provides functional capabilities such as reporting data from a sensor 101f to a server 105 or receiving instructions for an actuator 101y from a server 105. Other possibilities exist as well for the configuration or combination of components illustrated in FIG. 1b without departing from the scope of the present invention.
FIG. 1c 
FIG. 1c is a graphical illustration of components within a module, in accordance with exemplary embodiments. FIG. 1c is illustrated to show a combination of components useful for leveraging the efficient and secure communication techniques described in the present invention. In addition to the components illustrated in FIG. 1b above, module 101 can include a an eUICC 163, a battery 101k, a server public key 114, a wireless module private key 112, a connection to an actuator 101y, a USB interface 101v, a CPU wake controller 101u, a flash memory 101w, a symmetric key 127, a pre-shared secret key 129, a random number generator 128, cryptographic algorithms 141, a radio 101z, and other components illustrated in FIG. 1c. Not all of the components illustrated in FIG. 1c are required for many exemplary embodiments, and some of the components illustrated in FIG. 1c may also be optionally omitted in some exemplary embodiments.
The CPU 101b can comprise a general purpose processor appropriate for the low power consumption requirements of a module 101, and may also function as a microcontroller. A CPU 101b and a CPU wake controller 101u are depicted and described in connection with FIG. 1b of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, entitled “Systems and Methods for ‘Machine-to-Machine’ (M2M) Communications Between Modules, Servers, and an Application using Public Key Infrastructure (PKI),” which is hereby incorporated by reference in its entirety. Clock 160 can comprise a crystal oscillator generating sine or square wave outputs at a frequency to drive a system bus 101d, CPU 101b, and RAM 101e, in addition to other functionality. In exemplary embodiments, clock 160 can comprise a temperature-compensated crystal oscillator (TCXO), a voltage-controlled crystal oscillator (VCXO), or a voltage-controlled temperature-compensated crystal oscillator (VCTCXO), and other possibilities exist as well. Clock 160 could include circuits and logic to keep time while module 101 is both in an active state and a dormant state.
An eUICC 163 within module 101 can comprise an embedded universal integrated circuit card 163. An eUICC 163 can provide the equivalent functionality as physical UICC, where definitions for a physical UICC are included in ETSI TR 102 216 and ETSI TS 102 221 V11.0.0. An eUICC 163 in FIG. 1c can support exemplary requirements for an eUICC outlined in ETSI TS 103 383 v12.2, entitled “Smart Cards; Embedded UICC; Requirements Specification,” which is herein incorporated by reference in its entirety. An eUICC 163 as illustrated in FIG. 1c can be implemented within module 101 in several different ways, including (i) as a module program 101i recorded in a nonvolatile memory, such as, but not limited to, either flash memory 101w or ROM 101c, (ii) firmware within CPU 101b or another specialized processing unit within module 101, (iii) a physical UICC within module 101 that contains the eUICC 163, or (iv) a specialized circuit within a surface mount package that is soldered directly onto a circuit board of the module 101, including an 8-lead small outline non-leaded (SON-8) package. For the embodiment where an eUICC 163 comprises a module program 101i, the eUICC 163 could be loaded and installed within nonvolatile memory 101w in module 101 using the steps and procedures described for a module program 101i in FIG. 1b. Other possibilities exist as well for the physical implementation of an eUICC 163 within a module 101 without departing from the scope of the present invention. An eUICC 163 may also be referred to as an “electronic UICC”, an “electronic SIM” (eSIM), or an “embedded SIM” (also eSIM).
For embodiments where an eUICC 163 can be loaded into a RAM 101e or flash 101w memory, a CPU 101b could designate the RAM 101e or flash 101w memory containing the instructions and data for an eUICC 163 to be a protected memory. When (i) loaded with appropriate data (such as, but not limited to an activated eUICC profile 163b described below), and (ii) a profile for a mobile network operator or wireless network 102 is selected and activated, then an eUICC 163 can provide the equivalent functionality of a physical UICC. The eUICC 163, using an activated eUICC profile 163b, can provide the module 101 with network access credentials (such as an IMSI and key K), and network parameters (such as RF frequencies to use) in order to connect with wireless network 102. The eUICC 163, using an activated eUICC profile 163b, can record a secret shared network key K and also a network module identity such as an IMSI or globally unique temporary identifier (GTUI). The eUICC 163 can support standard steps by module 101 for network authentication contemplated in 3GPP TS 33.401 V12.9.0 and related standards, including inputting a RAND value and outputting an RES value.
According to an exemplary embodiment, an eUICC 163 can be recorded and operate within a “eUICC supporting” physical universal integrated circuit card (UICC) 166 within module 101. This “eUICC supporting”, physical UICC 166 can include a processing unit, RAM memory, ROM memory, EEPROM memory, a bus, and a physical interface in order to support a profile activation of multiple different received eUICC profiles 163a. The processing unit, RAM memory, ROM memory, EEPROM memory, and bus in an “eUICC supporting” UICC 166 could comprise smaller versions with similar or equivalent functionality of the CPU 101b, RAM 101e, ROM 101c, flash memory 101w, and bus 101d, respectively, depicted and described in FIG. 1b above for a module 101. In other words, a module 101 could include a connection and slot for a physical UICC card, and (i) a manufacturer, distributor, or end user could load an “eUICC supporting” UICC 166 into the slot, and (ii) the eUICC 163 could operate on the physical UICC.
The physical form-factor for an “eUICC supporting” UICC 166 could be identical to a UICC, and a difference between the two may not even be apparent upon visual inspection without special markings on the card. The physical form-factor for an “eUICC supporting” UICC 166 could comprise a “micro-SIM” or a “nano-SIM” as defined in ETSI TS 102 221 V11.0.0, which is herein incorporated by reference. When the module 101 detects a “eUICC supporting” UICC 166, the module 101 could send received eUICC profiles 163a (such as received using the IP network 107) to the “eUICC supporting” UICC 166, and also select, deselect, activate, and deactivate the different received eUICC profiles 163a recorded in the “eUICC supporting” UICC 166. When a module 101 detects that a regular UICC (i.e. not an “eUICC supporting” UICC 166) has been loaded into a slot for UICCs, the module 101 could access the UICC in a regular manner implemented by mobile phones and modules for connecting to existing wireless networks in 2013, such as LTE or 3G networks.
In addition to recording a received profile 163a and an activated profile 163b, an eUICC 163 can record an initial module private key 112b and a network public key 165b. An eUICC 163 can also record a plurality of received eUICC profiles 163a. The initial module private key 112b can be associated with an initial module public key 111b, as illustrated in FIG. 1a above. An eUICC subscription manager 164 could use the initial module public key 111b to encrypt the eUICC profile 163a, and a module 101 could use the initial module private key 112b to decrypt the eUICC profile received from the subscription manager 164, using an asymmetric ciphering algorithm 141a as described in FIG. 1d below. The eUICC subscription manager 164, assuming the eUICC subscription manager 164 is associated with M2M service provider 108, could sign the eUICC profile 163a using the network private key 165a (such as creating a server digital signature 506 as described in FIG. 5a below), and module 101 could verify the server digital signature 506 with the network public key 165b. The network public key 165b could be recorded in either (i) the eUICC 163 directly, and/or (ii) within the profile 163a. In either case, the initial module private key 112b, initial module public key 111b, an network PM keys 165a and 165b (as illustrated in FIG. 1a) can be useful for module 101 to authoritatively and securely receive eUICC profiles 163a. 
Sensor 101f could be a device to collect environmental data or data regarding a monitored unit 119. Sensor 101f could collect data such as, but not limited to, temperature, humidity, pressure, visible light levels, radiation, shock and/or vibration, voltage, current, weight, pH levels, orientation/motion, or the presence of specific chemicals. Sensor 101f could also be a microphone. Sensor 101f could be a magnetic strip reader for credit cards and similar cards, or an antenna for either near-field RF communications, such as, but not limited to, reading an RF identity tag. An antenna for a sensor 101f could also collect longer-range RF signals, such as, but not limited to, reading long-range radio frequency identity tags. Sensor 101f could also collect biometric data such as, but not limited to, heart rate, glucose levels, body temperature, or other health measurements and in this case monitored unit 119 could be a person. The sensor 101f can provide data to the CPU 101b in the form of analog or digital data, which can be communicated via a system bus 101d or physical interface 101a and other electrical interfaces are possible as well. A sensor measurement can comprise the analog or digital data collected by CPU 101b from sensor 101f. A sensor measurement can include processing of the analog or digital data input CPU 101b by sensor 101f, such as, but not limited to, averaging over time, using mathematic formulas to convert the raw data from sensor 101f into a usable form. Module 101 may also collect sensor data or sensor values using a sensor 101f and CPU 101b, where the data or values are derived from electrical signals output by a sensor 101f. A sensor measurement can comprise the sensor data or sensor values. If module 101 comprises a “point of presence” payment terminal, then a sensor measurement could comprise data read from a payment card.
As contemplated herein, the terms “sensor measurement” and “sensor data” can be used interchangeably, and can also be considered functionally equivalent. Although a single sensor 101f is shown in FIG. 1c, a module 101 could include multiple sensors. Each of the multiple sensors 101f could include a sensor identity 151, which could comprise a number or string to identify the sensor 101f. A sensor 101f could be external to module 101, and also a plurality of sensors 101f may be used and they also can connect to module 101 when module 101 uses radio 101z as a base station for a WiFi network. An exemplary embodiment where sensor 101f connects to module 101 using a radio 101z is also depicted and described in connection with FIG. 1e of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety.
Actuator 101y could be a device to control a parameter or state for a monitored unit 119, such as, but not limited to, changing a voltage or current, activating a switch or relay, turning on or off a microphone or speaker, activating or deactivating a light, and other examples are well known in the art. Actuator 101y could also be a speaker. Actuator 101y could be controlled by module 101 via a digital or analog output from CPU 101b, which could also be transmitted or sent via system bus 101d or a physical interface 101a. Although actuator 101y is illustrated as external to wireless module 101 in FIG. 1c, actuator 101y could also be internal to module 101, and module 101 could include multiple actuators 101y. The use of multiple actuators 101y each with an actuator identity 152 is also depicted and described in connection with FIG. 1e of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety. Sensors and actuators are well known to those of ordinary skill in the art, and thus are not described in additional detail herein.
Module 101 can include a Universal Serial Bus (USB) interface 101v. In accordance with an exemplary embodiment, module 101 can comprise a wireless module and include a radio 101z. Note that the use of a radio 101z is not required for module 101, which could also obtain a connection to the IP Network 107 via a wired line such as Ethernet. Although not depicted, radio 101z could include antennas for reception and transmission of RF signals, and even multiple antennas could be used. Although a single radio 101z is illustrated in module 101, module 101 could also contain multiple radios 101z. Radio 101z can support wireless LAN standards such as, but not limited to, WiFi, Bluetooth, and Zigbee, or similar wireless LAN standards. Radio 101z illustrated in FIG. 1c can comprise a radio 101z depicted and described in connection with FIG. 1d of U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, the contents of which are herein incorporated in their entirety.
Note that module 101 may also operate as a base station in a wireless LAN, such as, but not limited to, an 802.11 base station. When module 101 operates a wireless LAN, radio 101z can function as either a client/node and/or a base station 103 to support communication from other wireless nodes in physical proximity, such as, but not limited to, other nodes within an exemplary 50 meters. The other wireless nodes could comprise a sensor 101f and/or actuator 101y, and in this case a sensor could be referred to as a “networked sensor” and an actuator could be referred to as a “networked actuator”. Radio 101z functioning as a base station is depicted and described as a base station 103 is depicted and described in connection with FIG. 1d of U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, the contents of which are herein incorporated in their entirety.
In accordance with exemplary embodiments, module 101 can store module private key 112, server public key 114, and module identity 110, and a symmetric key 127 in memory/RAM 101e during operation, such as when CPU 101b is active and the module 101 is connected to a network such as a wireless network 102 during data transmissions. Module private key 112 can preferably be recorded in nonvolatile memory such as, but not limited to, flash memory 101w, so that module 101 has access to its private key 112 after the private key has been derived or loaded, including times when a battery 101k has been fully drained or removed from module 101 (if module 101 does not utilize a persistent power source such as land-line power).
Symmetric key 127 can be a secure, shared private key for use with symmetric encryption or symmetric ciphering algorithms 141b (in FIG. 1d below). Symmetric key 127 can be derived by using module public key 111 and/or server public key 114, possibly through the use of a key derivation function 141f (described in FIG. 1d below). Symmetric key 127 can be used for both encryption and decryption with symmetric cryptographic algorithms 141b described in FIG. 1d below, where a shared secret key can be used to encrypt/cipher and/or decrypt/decipher. Symmetric key 127 may also include an expiration time 133, such that symmetric key 127 may only be used by module 101 and/or server 105 during a limited period of time, such symmetric key 127 remaining only valid for a day, or a week, or during a session (where the session comprises multiple messages and/or responses between a module 101 and a server 105), etc. Module 101 can also derive symmetric key 127 according the Elliptic Curve Integrated Encryption Scheme (ECIES) and/or ECDH 159, discussed in FIG. 1d below, using module public key 111, server public key 114, and a random number 128a from random number generator 128. ECIES could be included in cryptographic algorithms 141. A summary of ECIES shared key derivation is described the Wikipedia article “Integrated Encryption Scheme” from Sep. 18, 2013 (herein incorporated by reference). Other possibilities for shared key derivation function using public keys are possible as well, including a Diffie-Hellman key exchange. Using a derived symmetric key from the exemplary key derivation function ECIES, module 101 and/or server 105 could derive a second symmetric key 127 after the expiration time 133 of the first symmetric key 127 had transpired. As contemplated herein, a symmetric key 127 can also comprise a session key, or the use of a “session key” with a symmetric ciphering algorithm 141b can comprise a symmetric key 127.
In an exemplary embodiment, a key derivation function 141f using public keys is not required to generate a shared symmetric key 127, and alternatively a shared symmetric key 127 could be generated by any of module 101, server 105, module provider 109, M2M service provider 108, or wireless network 102. If module 101 generates shared symmetric key 127 for symmetric ciphering 141b within a cryptographic algorithms 141, then module 101 can send shared symmetric key 127 to server 105 using an asymmetric ciphering depicted and described in connection with FIG. 4 below. In accordance with a preferred exemplary embodiment, module 101 preferably uses a random number generator 128 to generate a random number 128a (illustrated in FIG. 1d) for input into cryptographic algorithms 141, and the seed 128b in random number generator 128 could utilize data from a sensor 101f in order to generate a random number 128a with high entropy in the creation of symmetric key 127. Random number generator 128 and random number 128a are also depicted and described in connection with FIG. 1d of U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, the contents of which are herein incorporated in their entirety.
Module identity 110 is preferably a unique identifier of module 101, and could comprise a number or string such as, but not limited to, a serial number, an international mobile subscriber identity number (IMSI), international mobile equipment identity (IMEI), or an Ethernet media access control (MAC) address. According to an exemplary embodiment, module identity 110 can also comprise a serial number or string that is written into hardware of module 101 upon manufacturing or distribution of module 101 (also depicted and described in connection with a step 511 in FIG. 5b below). In this case, module identity 110 could be recorded in a read only memory 101c, where read only memory 101c could not be easily erased or otherwise tampered with. Read only memory 101c could also comprise a protected memory and the address for accessing the module identity 101 within the ROM 101c could comprise a protected address. A protected address can comprise an address accessible to a CPU 101b and readable by CPU 101b where the data within the protected address is not modified, changed, or updated by a CPU 101b under normal operating conditions. Also note that the protected address can comprise one form of a nonvolatile memory, where a memory records data. Or, module 101 could read module identity 110, which could be written into hardware by a manufacturer, distributor, or module provider 109, by using a device driver 101g that reads a hardware address containing the module identity 110 using the system bus 101d. In this case, the hardware address can comprise a protected address, as contemplated herein. Module 101 can read the module identity 110 by accessing a read-only address using the bus 101d. In either case, in many embodiments one form of a module identity 110 may preferably be permanently or persistently associated with the physical hardware of module 101, which can be helpful for the security procedures contemplated herein. Module identity 110 can function as a basic identifier for services from M2M service provider 108, wireless network 102, eUICC subscription manager 164, and/or server 105 in order to properly identify module 101 among a plurality of modules. Module private key 112 and module public key 111 could be unique to module 101 and uniquely associated with module identity 110, according to a preferred embodiment.
As contemplated herein, a module identity 110 can also have more than one use. A first module identity 110 could comprise a serial number for the physical hardware of module 101, as described in the paragraph above. A second module identity 110 could also comprise a session identifier, for data sessions between module 101 and server 105, where the session identifier can be uniquely associated by a server 105 to module 101. A third module identity 110 could comprise a network module to identify a module 101 with a wireless network 102. A fourth module identity 110 can be associated with the eUICC 163. In embodiments where module identity 110 has more than one use, format, or representation, the module identity 110 associated with or written into hardware of module 101 (and potentially read from a read-only address in module 101) may preferably comprise the module identity 110 used in a certificate 122. Since a module 101 may utilize multiple module public keys 111 and module private keys 112 over its lifetime, a certificate 122 for module 101 can preferably include both (i) the module identity 110 (such as, but not limited to, a serial number for the physical hardware of module 101) and (ii) a module public key identity 111a in order to specify the particular module public key 111 associated with certificate 122. The use of a module public key identity 111a in a certificate 122 is also depicted and described in connection with FIG. 1f below. Since a module 101 may also have multiple public keys 111 for different purposes (such as, but not limited to, one for creating digital signatures, another for asymmetric ciphering, another for use with a second wireless network 102, etc.), then module 101 may also potentially have multiple valid certificates 122 concurrently each with different module public key identities 111a. 
Further, as contemplated herein, a module identity 110 could also comprise more than one physical string or number, such as, but not limited to, a first string when module 101 connects with a first M2M service provider 108 or first wireless network 102, and module identity 110 could comprise a second string when module 101 connects with a second M2M service provider 108 or second wireless network 102. The first M2M service provider 108 or first wireless network 102 may have a first requirement or specification for the format, length, structure, etc. of module identity 110, and the second M2M service provider 108 or second wireless network 102 may have a second requirement or specification for the format, length, structure, etc. of module identity 110. In this manner, even though more than one string or number is used to identify a module 101, the two different strings or numbers could comprise a module identity 110.
Server public key 114 in module 101 could be obtained from downloading the key over the IP Network 107, or optionally also written into nonvolatile memory of module 101 upon manufacture or distribution. Server public key 114 could be obtained using a domain name or Internet address that is recorded in nonvolatile memory upon the configuration of module 101, such as, but not limited to, during installation or distribution, and module 101 could fetch the server public key 114 upon connecting to a wireless network 102 or other connection to the IP Network 107. Additional elements besides those depicted in FIG. 1c could also be recorded in volatile memory 101e, which could comprise a RAM 101e. For example, cryptographic algorithms 141, the shared secret keys 129, and the pre-shared secret key code 134 could also be recorded in RAM 101e as well. Note that values and related data can also be recorded in both RAM 101e and nonvolatile memory 101w at the same time, such that data in nonvolatile memory 101w allows module 101 to access the data after a shutdown state, but moving the same data into RAM 101e during an active state allows module 101 to more quickly perform operations using a CPU 101b. Other possibilities exist as well for the storage location of various values and data elements illustrated in FIG. 1c without departing from the scope of the present invention.
Module 101 may also contain cryptographic algorithms 141, which may comprise a suite of algorithms or subroutines that can be utilized for (i) deriving a pair of keys comprising a public key and a private key, (ii) encrypting data using public keys, (iii) decrypting data using private keys, (iv) processing secure hash signatures using private keys, and (v) verifying secure hash signatures using public keys, and related software, firmware, or subroutines for implementing a cryptographic system, including symmetric ciphering algorithms. Cryptographic algorithms 141 (also described below in FIG. 1d) could utilize publicly available software libraries within tools such as, but not limited to, OpenSSL maintained by The OpenSSL Project (http://www.openssl.org/), libgcrypt maintained by The Free Software Foundation (http://www.gnu.org/software/libgcrypt/), and similar libraries such as, but not limited to, libmcrypt and Crypto++. Note that cryptographic algorithms 141 could also use proprietary cryptographic libraries as well. In addition to implementing asymmetric encryption/ciphering, such as, but not limited to, used with RSA and ECC cryptography, cryptographic algorithms 141 can provide symmetric ciphering where a shared private key is utilized to both encrypt and decrypt, such as, but not limited to, with the Advanced Encryption Standard (AES) cipher suite.
As illustrated in FIG. 1c, module 101 may also contain a random number generator 128. Random number generator 128 may contain a seed 128b. The creation of random numbers with a high degree of entropy may be important the use of cryptographic algorithms 141. A plurality of the data as a source for a random number seed 128b could be appended together into a “module random seed file” 139 (illustrated in FIG. 1d) with a combined series or list of states (i.e. a plurality of sensor 101f measurements, radio 101z measurements, clock 160 times or values, memory 101e or memory 101w states, operating system 101h states, actuator 101y states, and/or hardware 101a or 101d states). Note that values or data for each of the elements listed in the previous sentence could be utilized in a “module random seed file” 139 instead of or in addition to a state. The “module random seed file” is also depicted and described in connection with FIG. 1e of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety
Note that the term “public key” as contemplated herein includes a key that may be shared with other elements, where the other elements may not be under the direct control of the same entity that holds the corresponding private key. However, the term “public key” as used herein does not require that the public key is made available to the general public or is publicly disclosed. An additional layer of security may be maintained in the present invention by preferably only sharing public keys on a confidential basis with other entities. For example, module public key 111 may be created by module 101 when generating module private key 112, and module 101 may share module public key 111 with M2M service provider 108 in order to record module public key 111 in server 105, but module 101 could choose to not (i) share module public key 111 with other entities, such as module provider 109 or (ii) provide a certificate 122 with module public key 111 publicly available on the IP Network 107. The benefits of confidentially sharing module public key 111 with server 105 are also further described below.
Although a single public key and private key for module 101 is illustrated in FIG. 1 c, both module 101 and server 105 may each utilize several different pairs of public keys and private keys. As one example, module 101 may record a first private key 112 used for creating a digital signature and a second private key 112 for decryption using asymmetric ciphering algorithms 141a. In this example, a server 105 could utilize a first module public key 111 to verify the digital signature, and a second module public key 111 could be utilized to encrypt messages sent to module 101. Similarly, either module 101 or server 105 may use private key 112 or 105c, respectively, to derive secondary shared keys such as, but not limited to, a derived shared key 129b below. Thus, one key pair could be used with digital signatures, a second key pair used for asymmetric ciphering, and a third key pair to derive shared secret keys. Each of the three illustrated pairs of keys could comprise a set of keys, and each of the illustrated pairs of keys could also use a different set of cryptographic parameters 126 (illustrated in FIG. 1g below), although the cryptographic parameters 126 for the various pairs of keys could also be the same.
In addition, module 101 could utilize a first set of keys to communicate with a first M2M service provider 108 and a second set of keys to communicate with a second M2M service provider 108. The first set of keys could use or be associated with a first set of cryptographic parameters 126 and the second set of keys could use or be associated with a second set of cryptographic parameters 126. According to exemplary embodiments, module 101 may also include a pre-shared secret key 129a. Pre-shared secret key 129a can comprise a secret key that is shared between module 101 and server 105 before module 101 begins (i) communicating with server 105 and/or a certificate authority 118, (ii) or utilizing PKI-based encryption and authentication to communicate with M2M service provider 108. Server 105 could also record the pre-shared secret key 129a, and a pre-shared secret key 129a can be associated with each module 101 using a module identity 110. A pre-shared secret key 129a is also depicted and described in connection with U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety. In an exemplary embodiment, once the pre-shared secret key 129a has been utilized to authenticate or verify either (i) a module public key 111 or (ii) module 101 with a server 105 (such as, but not limited to, using subsequent steps 517 in FIG. 5b below), then that particular pre-shared secret key 129a may be “discarded” and not used again for security purposes contemplated herein.
Note that the use of a pre-shared secret key 129a and pre-shared secret key code 134 is also optional, such that a module program 101i could cipher of obfuscate the initial submission of a derived module public key 111 and module identity 110 to a server 105, so that server 105 could be reasonably assured only a valid module 101 submitted the module public key 111. According to a preferred exemplary embodiment, module 101 can derive its own module private key 112 and module public key 111, and utilize pre-shared secret key 129a in order to securely and/or authoritatively communicate the derived module public key 111 with server 105 and/or a certificate authority 118. The use of pre-shared secret key 129a can be particularly useful if module 101 has already been deployed with a monitored unit 119 and connects to server 105 though the IP Network 107 for the very first time. Server 105 could preferably utilize pre-shared secret key 129a in order to confirm that a received module public key 111 and module identity 110 from module 101 authoritatively belong to module 101, as opposed to being an unauthorized or even fraudulent submission of module public key 111 and module identity 110. As contemplated herein, a pre-shared secret key 129a can also comprise (i) an initial module private key 112b for module 101, and (ii) an initial module public key 111b for server 105. In this manner, the specific number of value for a pre-shared secret key 129a does not need to be equal on both the module 101 and the server 105.
Server 105 could utilize a pre-shared secret key 129a and the steps depicted and described in connection with FIG. 4 and FIG. 5b below in order to securely receive module public key 111 and module identity 110 from module 101, including the first time module 101 sends module public key 111 to server 105. As one example, pre-shared secret key 129a could be utilized as a symmetric ciphering 141b key, described in FIG. 1d below. After the first submission of module public key 111 to server 105, any subsequent submissions of new module public keys 111 derived by module 101 could either (i) continue to use the pre-shared secret key 129a, or (ii) use a symmetric key 127 derived after the first module public key 111 has been received. Securing the submission of module public key 111 with server 105, including both the first submission and subsequent submissions, is also depicted and described in connection with FIG. 5b below.
FIG. 1d 
FIG. 1 d is a graphical illustration of components in a set of cryptographic algorithms, in accordance with exemplary embodiments. As contemplated herein, communications with module 101 can be secured by using cryptographic algorithms 141. The cryptographic algorithms 141 used by module 101, server 105, or other servers can comprise a set of steps, procedures, or software routines for accomplishing steps to cipher, decipher, sign, and verify messages, including the generation of public keys, private keys, and derived shared keys, including symmetric keys. Cryptographic algorithms 141 can be implemented in software or firmware operating on (i) module 101 in the form of a module program 101i or an eUICC 163, or (ii) wireless network 102 or M2M service provider 108 in the form of a server 105, where server 105 generates tokens for the authentication of a module 101 and mobile phones connecting with wireless network 102. Example software for a cryptographic algorithms 141 includes the libraries within the openssl, libmcrypt, and/or and Crypto++ discussed in FIG. 1c. Other possibilities for the location of cryptographic algorithms 141 within a module 101, server 105, or wireless network 102 exist as well, including possibly module operating system 101h and a server operating system 105h (described in FIG. 1k below).
In addition, cryptographic algorithms 141 may be implemented in hardware or firmware on any of module 101, server 105, or M2M service provider 108. Note that module 101, server 105 and M2M service provider 108 could each utilize a different set of cryptographic algorithms 141, although the sets of algorithms should preferably be fully interoperable (i.e. ciphering with a first symmetric ciphering algorithm 141b and a symmetric key 127 on module 101 could be deciphered by a second symmetric ciphering algorithm 141b on server 105 using the symmetric key 127, etc.). As illustrated in FIG. 1d, cryptographic algorithms 141 may comprise an asymmetric ciphering algorithm 141a, a symmetric ciphering algorithm 141b, a secure hash algorithm 141c, a digital signature algorithm 141d, a key pair generation algorithm 141e, a key derivation function 141f, a random number generator 128, and the other algorithms depicted in FIG. 1 d. 
Asymmetric ciphering algorithms 141a can comprise algorithms utilizing public key infrastructure (PKI) techniques for both (i) encrypting with a public key and (ii) decrypting with a private key. Example algorithms within asymmetric algorithms 141a include the RSA algorithms 153 and the Elliptic Curve Cryptography (ECC) algorithms 154, and other asymmetric algorithms could be utilized as well. For example, either the ECC algorithms 154 or RSA algorithms 153 can be used for encryption and decryption, including (i) encryption step 402 discussed below in FIG. 4, as well as (ii) decryption step 514 discussed below in FIG. 5a. A set of cryptographic parameters 126 can include input into asymmetric ciphering algorithms 141a, such as, but not limited to, specifying key lengths, elliptic curves to utilize (if ECC), modulus (if RSA) or other parameters or settings required. As contemplated herein and described in additional detail below, the algorithms illustrated in FIG. 1 d can perform both ciphering and deciphering, using the appropriate keys. Although RSA algorithms 153 and ECC algorithms 154 are illustrated within an asymmetric ciphering algorithm 141a, a RSA algorithm 153 and ECC algorithm 154 could also be associated with a key pair generation algorithm 141e and other elements within a set of cryptographic algorithms 141, and thus not exclusively used within a set of cryptographic algorithms 141 by an asymmetric ciphering algorithm 141a. 
The use and application of RSA algorithms and cryptography are described within IETF RFC 3447 titled “Public-Key Cryptography Standards (PKCS) #1: RSA Cryptography Specifications Version 2.1”, herein incorporated by reference, among other published standards for the use of RSA algorithms 153. The use of an RSA algorithm 153 for encryption and decryption, including with cryptographic algorithms 141 and other description of encryption or decryption algorithms, can also be processed according to the description of the RSA algorithm according to the Wikipedia entry for “RSA (algorithm)” as of Sep. 9, 2013, which is incorporated by reference herein.
The use and application of ECC algorithms 154 for asymmetric ciphering algorithms 141a within cryptographic algorithms 141 are described within IETF RFC 6090 titled “Fundamental Elliptic Curve Cryptography Algorithms” (herein incorporated by reference), among other published standards using ECC. ECC algorithms 154 can also utilize elliptic curve cryptography algorithms to the Wikipedia entry for “Elliptic curve cryptography” as of Sep. 9, 2013, which is incorporated by reference herein. ECC algorithms 154 may utilized according to exemplary preferred embodiments in order to maintain high security with smaller key lengths, compared to RSA, thereby helping to comparably reduce the message lengths, radio frequency spectrum utilization, and processing power required by module 101. Thus, the use of ECC algorithms 154 within various steps requiring ciphering or digital signatures may help conserve battery life of module 101 while maintaining the objective of securing system 100 and other systems illustrated herein. Note that as contemplated herein, other algorithms besides with ECC algorithms 154 and RSA algorithms 153 may be also be used in asymmetric algorithms 141a and also a key pair generation algorithm 141e. 
Cryptographic algorithms 141 may also include a set of symmetric ciphering algorithms 141b. Symmetric ciphering algorithms 141b can utilize a symmetric key 127 by one node such as a module 101 to encrypt or cipher data, and the encrypted data can be decrypted or deciphered by server 105 also using the symmetric key 127. Examples of symmetric ciphers include Advanced Encryption Standard 155 (AES), as specified in Federal Information Processing Standards (FIPS) Publication 197, and Triple Data Encryption Standard (Triple DES), as described in NIST Special Publication 800-67 Revision 1, “Recommendation for the Triple Data Encryption Algorithm (TDEA) Block Cipher (Revised January 2012)”. Cryptographic parameters 126 input into symmetric ciphering algorithms 141b can include symmetric key 127 length, such as, but not limited to, the selection of 128, 192, or 256 bits with AES 155 symmetric ciphering, and cryptographic parameters 126 could also select a symmetric ciphering algorithm in a collection of symmetric ciphering algorithms 141b. Other examples of symmetric ciphering algorithms 141b may be utilized as well within cryptographic algorithms 141. Also note that as contemplated herein, the term “symmetric ciphering” contemplates the use of a symmetric key 127 in order to encrypt or cipher data with a symmetric ciphering algorithm 141b, and “asymmetric ciphering” contemplated the use of an asymmetric ciphering algorithm 141a to encrypt or cipher data with a public key, such as module public key 111 or server public key 114.
Cryptographic algorithms 141 may also include a set of secure hash algorithms 141c in order to compute and output a secure hash value or number based on a string or file input into the secure hash algorithms 141c. Example secure hash algorithms include SHA256 156 (also known as SHA-2) and SHA-3 157. SHA256 156 is specified in the National Institute of Standards and Technology (NIST) Federal Information Processing Standards Publication (FIPS PUB) 180-2 titled “Secure Hash Standard”. SHA-3 157 is scheduled to be published in FIPS PUB 180-5. Cryptographic parameters 126 input into secure hash algorithms 141c can include the selection of the length of the secure hash, such as, but not limited to, using 224, 256, or 512 bits with either SHA-2 or SHA-3, and other possibilities exist as well.
Cryptographic algorithms 141 may also include a set of digital signature algorithms 141d, in order to sign and verify messages between (i) module 101 and server 105 or (ii) server 105 and wireless network 102. Digital signature algorithms 141d can also verify signatures such as, but not limited to, comparing that (i) a first secure hash value in the form of a digital signature in a certificate (not shown) using a certificate authority public key matches (ii) a second secure hash value in the certificate (not shown). Digital signature algorithms 141d can utilize algorithms in National Institute of Standards (NIST) “FIPS 186-4: Digital Signature Standard”, or IETF RFC 6979 titled “Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)”. The use of ECDSA algorithm 158 within a set of digital signature algorithms 141d may be preferred if keys such as, but not limited to, module public key 111 and server public key 114 are based on elliptic curve cryptography. The use of the Digital Signature Standard can comprise a DSA algorithm 167. Other PKI standards or proprietary techniques for securely verifying digital signatures may be utilized as well in digital signature algorithms 141d. Cryptographic parameters 126 input into digital signature algorithms 141d can include the selection of a secure hash algorithms 141c to utilize with digital signature algorithms 141d, or the algorithm to utilize, such as, but not limited to, ECDSA 158 shown or an RSA-based alternative for digital signatures is possible as well. Cryptographic parameters 126 input into digital signature algorithms 141d can also include a padding scheme for use with a digital signature algorithms 141d. Digital signature algorithms 141d could also include an RSA digital signature algorithm for use with RSA-based public and private keys.
Cryptographic algorithms 141 may also include key pair generation algorithms 141e, a key derivation function 141f, and a random number generator 128. Key pair generation algorithms 141e can be utilized by module 101, server 105, or network 102 to securely generate private and public keys. The key pair generation algorithms 141e can also use input from a cryptographic parameters 126, such as, but not limited to, the desired key lengths, or a value for an ECC curve if the public key will support ECC algorithms 154. According to an exemplary preferred embodiment, module 101 can derive a pair of module public key 111 and module private key 112 using key pair generation algorithms 141e. Software tools such as, but not limited to, openssl and libcrypt include libraries for the generation key pairs, and these and similar libraries can be used in a key pair generation algorithm 141e. 
Key derivation function 141f can be used by module 101, server 105, and/or wireless network 102 in order to determine a common derived shared secret key 129b, using at least two numbers as input. In exemplary embodiments, one of the two numbers as input can comprise one of (i) a private key, or (ii) a secret shared key 129. The other of the two numbers input into a key derivation function 141f could comprise at least one number from (i) a set of cryptographic algorithms 126 or (ii) a key exchange token 906 (in FIG. 9b below) that is commonly shared between two nodes utilizing a key derivation function 141f in order to process or obtain the same derived shared secret key 129b. A key exchange to share a common symmetric key 127 can be performed using a key derivation function 141f and cryptographic parameters 126, in addition to using public and/or private keys in some embodiments. In exemplary embodiments, three values comprising (i) a private key, (ii) a token such as a public key or a random number, and (iii) values from a set of cryptographic parameters 126 can be input into the key derivation function 141f in order to output a derived shared secret key 129b. 
An exemplary algorithm within a key derivation function 141f can be the Diffie-Hellman key exchange, which is used by tools such as, but not limited to, secure socket layer (SSL) with RSA algorithms 153. When using ECC algorithms 154, module 101 and server 105 can utilize Elliptic Curve Diffie-Hellman (ECDH) algorithms 159, and a summary of ECDH is included in the Wikipedia article titled “Elliptic Curve Diffie-Hellman” (http://en.wikipedia.org/wiki/Elliptic_curve_Diffie%E2%80%93Hellman from Sep. 24, 2013, which is herein incorporated by reference. Other algorithms to derive a shared secret key 129b using public keys, private keys, and tokens may also be utilized in a key derivation function 141f, such as, but not limited to, the American National Standards Institute (ANSI) standard X-9.63 160. Cryptographic parameters 126 used with key derivation function 141f with elliptic curve cryptography can include a common base point G for two nodes using the key derivation function 141f and public keys. The base point G in a cryptographic parameters 126 can be transmitted or sent from a module 101 to a server 105 in a message 208, and the base point G can be sent from a server 105 to a module 101 in a response 209, and other possibilities exist as well, including recording the base point G within a received eUICC profile 163a. Cryptographic parameters 126 can also include other or additional information for using a key derivation function 141f in order to derive either (i) a commonly shared symmetric key 127, or (ii) a commonly shared secret key 129b. Other possibilities for a key derivation function 141f exist as well without departing from the scope of the present invention.
Cryptographic parameters 126 input into key pair generation algorithms 141e can include the type of asymmetric ciphering algorithms 141a used with the keys, the key length in bits, an elliptic curve utilized for ECC, a time-to-live for a public key that is derived, and similar settings. Additional cryptographic parameters 126 for a public key can include a supported point formats extension, where the supported point formats extension could comprise uncompressed, compressed prime, or “compressed char2” formats, as specified in ANSI X-9.62. In other words, an ECC public key can have several formats and a set of cryptographic parameters 126 can be useful to specify the format. Although a set of cryptographic parameters 126 is illustrated in FIG. 1 d as internal to cryptographic algorithms 141, parameters 126 could be recorded in other locations in a module 101 or a system 100. As one example, a set of cryptographic parameters 126 could be recorded in a server 105 and downloaded by module 101 using the IP Network 107. The various algorithms within cryptographic algorithms 141 may utilize a random number generator 128, which is also depicted and described in connection with FIG. 1c above. As contemplated herein, the term “cryptographic parameters” 126 may be considered equivalent to a “set of cryptographic parameters” 126, and also use of the terms “parameters” 126 and “set of parameters” 126 can both refer to the cryptographic parameters 126 illustrated in FIG. 1d and FIG. 1e. Cryptographic parameters 126 are also further depicted and described in connection with FIG. 1e below.
According to a preferred exemplary embodiment, cryptographic parameters 126 can include values to define an elliptic curve and/or use ECC algorithms 154. A set of ECC parameters 137 could comprise values or numbers for an elliptic curve defining equation. ECC parameters 137 are also depicted and described in FIG. 1g of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety. Cryptographic parameters 126 could also include an ECC standard curve 138, which could comprise a name and/or values for a standardized curve, such as, but not limited to, the list of named curves included in section 5.1.1 of IETF RFC 4492 titled “Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS).”
As contemplated herein, a set of cryptographic algorithms 141 may operate using either strings or numbers, and cryptographic parameters 126 could include either strings or numbers as well. As contemplated herein (i) a collection, sequence, and/or series of numbers could comprise a string, (ii) a string can include a mixture of numbers and characters, or (iii) a string can comprise a collection, sequence, and/or series of characters or bits. The processing of cryptographic algorithms 141 within a module 101 can take place within a CPU 101b, or module 101 could also process cryptographic algorithms in a cryptographic processing unit (not shown) connected to the system bus 101d. An eUICC 163 could also include a set of cryptographic algorithms 141, in addition to a separate set of cryptographic algorithms 141 being recorded in a flash memory 101w for module 101. According to an exemplary embodiment, a module 101 or a server 105 could include a cryptographic processing unit (not shown) separate from the CPU 101b in order to increase efficiency or security for supporting the use of cryptography through a system 100. An eUICC 163 could comprise the separate cryptographic processing unit. Alternatively, in exemplary embodiments cryptographic algorithms 141 can be implemented entirely in software within a module 101 and/or server 105, and also utilized by a module program 101i, data reporting steps 101x, and other software such as operating system 101h. 
FIG. 1e 
FIG. 1e is a graphical illustration of an exemplary system, where a module and a server exchange a set of cryptographic parameters and a subset of the set of cryptographic parameters, in accordance with exemplary embodiments. In exemplary embodiments, a first node can send a set of cryptographic parameters 126 to a second node, and the second node can send a subset of cryptographic parameters 126a to the first node. In an exemplary embodiment, a server 105 can send the set of cryptographic parameters 126 to a module 101, and the module 101 can send the subset of the cryptographic parameters 126a to the server 105. The module can select the subset of cryptographic parameters 126a according to the capabilities of a module program 101i and/or a set of cryptographic parameters 141 recorded in the module 101. In another exemplary embodiment, a module 101 can send the set of cryptographic parameters 126 to a server 105 (or a set of servers 1010 illustrated in FIG. 10), and the server 105 can send the subset of the cryptographic parameters 126a to the module 101.
In this manner, using the steps illustrated in FIG. 1 e, the two nodes can select and agree on a subset of cryptographic parameters 126a for use with a set of cryptographic algorithms 141. The exemplary values for a set of cryptographic parameters 126 are shown in FIG. 1e to be illustrative as opposed to limiting, and other values or fields for a set of cryptographic parameters 126 are possible as well without departing from the scope of the present invention. As contemplated herein, a subset of cryptographic parameters 126a can also comprise a set of cryptographic parameters 126. Although not depicted in FIG. 1e, a node receiving a subset of cryptographic parameters 126a could send an acknowledgement upon receipt to signal the subset of cryptographic parameters 126a had been properly received in a valid or acceptable format and also implemented in communication with the other node.
In addition, both the set of cryptographic parameters 126 and the subset of cryptographic parameters 126a can be transmitted in a ciphertext form in order to increase security. In an exemplary embodiment, server 105 can send the set of cryptographic parameters 126 in a server encrypted data 504 (depicted and described in connection with FIG. 5a below), and the module 101 can respond with a subset of cryptographic parameters 126a in a module encrypted data 403 (depicted and described in connection with FIG. 4 below). The set of cryptographic parameters 126 or 126a could be encrypted with a symmetric key 127, where in an exemplary embodiment the symmetric key 127 could comprise a pre-shared secret key 129a depicted and described in connection with FIG. 1d of U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, which is incorporated by reference in its entirety. Or, the symmetric key 127 for encrypting a set of cryptographic parameters 126 or 126a could comprise a shared secret key 129c as described in FIG. 1c herein.
In exemplary embodiments, module 101 and server 105 could pre-agree to a base set of cryptographic parameters 126 different than the set of cryptographic parameters 126 illustrated in FIG. 1e, and the pre-agreed base set of cryptographic parameters 126 could be used with a set of cryptographic algorithms 141 to establish a symmetric key 127 in order to encrypt the set of cryptographic parameters 126 or 126a. In addition, the set of cryptographic parameters 126 or 126a could be ciphered using an asymmetric ciphering algorithm 141a and a public key of the other node, and sent to the receiving node to decrypt using the private key of the receiving node. The algorithms used to cipher a set of cryptographic parameters 126 in an asymmetric ciphering algorithm 141a could be pre-agreed, and a different set of asymmetric ciphering algorithms 141a could be selected after processing the received set of cryptographic parameters 126. Other possibilities for encrypting a set of cryptographic parameters 126 or 126a exist as well without departing from the scope of the present invention. Alternatively, the set of cryptographic parameters 126 and/or 126a could be sent between two nodes as plaintext within an IP packet.
The set of cryptographic parameters 126 can include a list of available options for a set of asymmetric ciphering algorithms 141a, symmetric ciphering algorithms 141b, secure hash algorithms 141c, digital signature algorithms 141d, a key pair generation algorithm 141e, and also general cryptographic parameters 126b. Although not depicted in FIG. 1 e, a set of cryptographic parameters 126 could also include parameters for a key derivation function 141f, a shared secret algorithm 141g, and a secret ciphering algorithm 141h. In an exemplary embodiment, the list of available options for a set of asymmetric ciphering algorithms 141a could comprise a list of ECC standard curves 138 and also ECC parameters 137 which could comprise a list of numbers or values for an elliptic curve defining equation. A module 101 and a server 105 could utilize a custom or non-standard elliptic curve defining equation by sending and/or receiving a set of ECC parameters 137 in a set of cryptographic parameters 126. Or, as illustrated in FIG. 1e, a node could select an ECC standard curve 138 from a list in a set of cryptographic parameters 126. A set of cryptographic parameters 126 could include a private key length 126e for deriving a module private key 112. A node could take similar steps for selecting an option from a list of available options for other fields as well in a set of cryptographic parameters 126 such as, but not limited to, symmetric ciphering algorithms 141b, secured hash algorithms 141c, etc. as illustrated in FIG. 1 e, in order to derive a subset of cryptographic parameters 126a. 
General parameters 126b can include a list of values that can be utilized in a set of cryptographic algorithms 141. General parameters 126 could specify values for using and/or the format of (i) a security token 410, (ii) an algorithm for processing an encrypted module identity string 110a, (iii) a certificate 122, (iv) a public key identity 111a, (v) the authentication means of a derived public key 111 in a step 517 depicted and described below in connection with FIG. 5b, (vi) a padding scheme 126c for the set of cryptographic algorithms 141, and/or (vii) key encoding rules 126d. Key encoding rules 126d can specify the format for sending and receiving a public key, such as the format of a derived module public key 111 sent to a server 105 in a step 516 depicted and described in connection with FIG. 5b below. Numerals depicted in FIG. 1e with a general parameters 126b include a “′” so show an association with the fields shown, as opposed to comprising the elements themselves. For example, the value of “security token length: 8 bytes” in a general parameters 126b with a label of “401′” illustrates the value of “security token length: 8 bytes” is associated with a security token 401 as opposed to being an exemplary the value for a security token 401. Likewise, the value of “Public Key Identity: yes” with a label of 111a′ illustrates that a general parameters 126b can specify a value for using a public key identity 111a as opposed to a public key identity 111a comprising a value of “Public Key Identity: yes”, etc.
Within a general parameters 126b in a set or subset of a cryptographic parameters 126, a field associated with module identity 110, illustrated as “110′”, can specify an algorithm to use for ciphering or obfuscating a module identity 110. A general parameters 126b could specify the use of a secret ciphering algorithm ciphering 161 for encrypting a module identity 110. In an exemplary embodiment, the general parameters 126b can specify the method of authentication for a derived module public key 111, where the module 101 could use a step 517 below. Exemplary values in a general parameters 126b for the authentication of a derived module public key 111 include, but are not limited to, message digest with a secret key, ciphering with a symmetric key 127, authenticating with a pre-shared public key, and module 101 sending a module digital signature 405 depicted and described in connection with FIG. 4 below. In accordance with preferred exemplary embodiments, a set of cryptographic parameters 126, possibly in a set of general parameters 126b, can include both (i) values for a module 101 to use with a set of cryptographic parameters 141 for deriving a new module public key 111 and new module private key 112, and (ii) steps or values for a module 101 to authenticate the new, derived module public key 111 with a server 105.
The set of cryptographic parameters 126 illustrated in FIG. 1e for a module 101 and the subset of cryptographic parameters 126a may be different than conventional technology, since the module 101 can select appropriate parameters or values for deriving its own module public key 111 and module private key 112, as well as changing the parameters or values over time for the generation of subsequent or new module public keys 111 and module private keys 112. Although not depicted in FIG. 1e, general parameters 126b could also include a time value for module 101 to refresh the set of cryptographic parameters 126 with server 105, such as periodically checking for a change in a preferred set of cryptographic parameters 126. In order to minimize bandwidth and also power consumption for a module 101, an exemplary time value for module 101 to check with server 105 for a new set of cryptographic parameters 126 could be an exemplary every 30 days. In another embodiment, server 105 could simply send a new set of cryptographic parameters 126 to module 101 each time new values may applicable.
As contemplated herein, a module 101 may be deployed with a monitored unit 119 for an extended period such as several years or longer, and a module public key 111 with a limited validity date could expire. In this case, after an extended period such as years, a preferred set of cryptographic parameters 126 could change, such as movement to longer private key lengths 126e, or the use of a new set of ECC standard curves 138. In this case, when a new module public key 111 is required, possibly due to the expiration of a prior module public key 111, module 101 could receive a new set of cryptographic parameters 126 and send a subset of the cryptographic parameters 126a before deriving a new module private key 112 and a new module public key 111 using the subset of cryptographic parameters 126a and a set of cryptographic algorithms 141. In exemplary embodiments, a set of cryptographic parameters 126 or subset of cryptographic parameters 126a used by a module 101 can change over time.
A set of cryptographic parameters 126 could specify additional information to the exemplary data shown in FIG. 1e. Within a set of general parameters 126b, a name or address of a certificate authority 118 could be included, where module 101 could send a module public key 111 derived using a step 515 depicted and described in connection with FIG. 5b. A set of cryptographic parameters 126 could include other names and addresses of servers, such as a first server 105 in a set of servers 1010 where module 101 would first authenticate module identity 110 and obtain a symmetric key 127, and module 101 could then communicate with a second server 105 using the symmetric key 127. A set of cryptographic parameters 126 could specify that the source of new module private key 112 and module public key 111 could be internally derived by module 101, as opposed to module 101 seeking a new module private key 112 from a local source, such as via a local network or a physical interface such as USB interface 101v. In addition, a set of cryptographic parameters 126 could include values for a random number generator 128, such as specifying the use of a seed 128b, or a module seed file 139, or the minimum length of a random number 128a. In addition, a plurality of different shared secret algorithms 141g and secret ciphering algorithms 141h could be used by a module 101 and a server 105, and specific shared secret algorithms 141g and secret ciphering algorithms 141h can be selected in a set of cryptographic parameters 126.
In exemplary embodiments, although not depicted in FIG. 1e, a set of cryptographic parameters 126 or 126a can specify the use of multiple module private keys 112 and module public keys 111 concurrently. In an exemplary embodiment, a module 101 could use a first module private key 111 with asymmetric ciphering algorithms 141a for receiving symmetric keys 127, and a second module private key 111 for deriving or calculating a module digital signature 405 (in FIG. 4 below). Further, a module 101 could communicate with a plurality of servers 105, where a first server 105 could use a first set of cryptographic parameters 126 and a second server could use a second and different set of cryptographic parameters 126. In order to maintain compatibility with the different servers 105, a module 101 could use (i) a first module private key 112 and first module public key 111 that was derived using the first set of cryptographic parameters 126 for communicating with the first server 105, and (ii) a second module private key 112 and second module public key 111 that was derived using the second set of cryptographic parameters 126 for communicating with the second server 105. In order to keep track of potentially multiple sets of cryptographic parameters 126 and/or subsets of cryptographic parameters 126a, a module 101 and/or a server 105 could implement a set of cryptographic parameters token 126c. The token 126c, illustrated as an exemplary “Set A” in FIG. 1e, can be a value to represent a collection of cryptographic parameters 126, and subsequently either module 101 or server 105 could refer to the set of cryptographic parameters 126 using the set of cryptographic parameters token 126c instead of communicating the full set of cryptographic parameters 126.
As contemplated herein, a set of cryptographic parameters 126 could also include values for a module 101 to authenticate or communicate with one or multiple wireless networks 102. In an embodiment, a wireless network 102 could require a specific symmetric ciphering algorithm 141b, and also a specific key derivation function 141f for generating derived shared keys 129b, and the specific values needed for module 101 to communicate with a wireless network 102 could be sent in a set of cryptographic parameters 126. Other possibilities exist as well to those of ordinary skill in the art without departing from the scope of the present invention.
FIG. 1f 
FIG. 1f is an illustration of a certificate that includes a PKI public key, where the key comprises an elliptic curve cryptography (ECC) key, in accordance with exemplary embodiments. Public and private keys in system 100 and other systems contemplated herein can utilize PKI techniques other than RSA, such as the elliptic curve cryptography (ECC) public key 111 illustrated in FIG. 1h. One benefit of using ECC is that an equivalent level of security can be obtained for a much smaller key length. Also, energy may be conserved using ECC algorithms 154 compared to RSA algorithms 153. An analysis of the energy conserved for ciphering, deciphering, signing, and verifying messages using ECC versus RSA is included in the paper titled “Energy Analysis of Public-Key Cryptography on Small Wireless Devices” by Wander et al (herein incorporated by reference). Smaller key lengths save bandwidth, memory, processing resources, and power, which are all valuable for a module 101 to conserve a battery 101k and usage of radio-frequency spectrum. For example, an ECC key length of 283 bits provides security similar to an RSA key length of approximately 2048 bits. Module public key 111 can comprise an ECC key in an X.509 certificate, as illustrated in FIG. 1f. 
Certificate 122 could include a signature 123, where signature 123 can be signed using ECC signature techniques, such as the Elliptic Curve Digital Signature Algorithm (ECDSA) 158 with a secure hash such as SHA256 156. A signature 123 in a certificate 122 containing an elliptic public key 111 could also be signed using a DSA algorithm 167. In order to generate signature 123, the private key associated with either CA 118 or module provider 109 may also be an ECC-based private key (for ECDSA 158). Note that the public key 111 in a certificate 122 could use a different asymmetric ciphering algorithm 141a than the algorithm used for signing, such that the public key 111 can be an ECC key, while the signature 123 could be generated with RSA algorithm 153 and/or key. Certificate 122 may also include a subset of cryptographic parameters 126a (or “parameters 126a”), where parameters 126a can specify an elliptic curve utilized with the module public key 111. Parameters 126a could also include the start and end times for the validity of either public key 111 or certificate 122. Other parameters 126a can be utilized in a certificate 122 as well, including parameters 126a recording a modulus for an RSA algorithm 153.
Certificate 122 illustrated in FIG. 1f also illustrates an exemplary embodiment of the present invention. Over the lifetime of a module 101, which could be a decade or longer, multiple module public keys 111 may be utilized. Exemplary reasons for the potential use of multiple different module public keys 111 include (i) the expiration of a certificate 122 (including expiration of a public key associated with a certificate authority 118 used in signature 123), (ii) a need to change an elliptic curve specified in a parameters 126, (iii) adding a new public/private key pair for connection with a different wireless network 102, (iv) as increasing a key length utilized in a public/private key pair, (v) the transfer of ownership or control of module 101, and/or (vi) module 101 connecting to a new server 105 that utilizes a different asymmetric ciphering algorithm (i.e. RSA instead of ECC). Other possibilities exist as well for reasons a module to derive a new module public key 111. Note that the multiple module public keys 111 may also be utilized concurrently, such that (i) a first module public key 111 in a first certificate 102 can be utilized with a first server 105, and (ii) a second module public key 111 (possibly derived using a different set of parameters 126 including using a different elliptic curve or asymmetric ciphering algorithm) can be utilized with a second server 105 and/or wireless network 102.
In either case of (i) module 101 using multiple module public keys 111 concurrently, or (ii) module 101 using different module public keys 111 in sequence, a certificate 122 can preferably include a module public key identity 111a to specify the module public key 111 utilized in a certificate 122. As illustrated in FIG. 1f, the module public key identity 111a could be included in the CN field, and the module identity 110 can be included in the OU field. Alternatively, the module public key identity 111a and module identity 110 can be appended together and used in the CN field. In this manner and according to preferred exemplary embodiments, a module public key identity 111a is utilized with both a module identity 110 and a module public key 111 within a certificate 122. Also, as noted previously herein, the use of a certificate 122 may optionally be omitted, such that module 101 and server 105 share public keys without using certificates 122, or a server 105 could use a certificate 122 and module 101 may omit a certificate 122 and other possibilities exist as well.
FIG. 2
FIG. 2 is a graphical illustration of an exemplary system, where a module sends a message to a server, and where the module receives a response to the message, in accordance with exemplary embodiments. Module 101 as depicted and described in FIG. 2 can operate as a wireless module 101, although a wired connection to the IP Network 107 could alternatively be utilized. System 200 as illustrated in FIG. 2 includes RF signals 201, module IP address 202, port number 203, module IP:port 204, server port number 205, server ID 206, server IP:port number 207, message 208, response 209, wireless network firewall address 210, and firewall port binding packet 211. Many of the elements illustrated within system 200 in FIG. 2 are also depicted and described in connection with FIG. 2 of U.S. patent application Ser. No. 14/039,401 (the contents of which are hereby incorporated by reference in their entirety). As contemplated herein, a wireless module 101 can comprise a module 101, or in other words a wireless module 101 may be a module 101 that is wireless. Functions described as being performed by a wireless module 101 may also be performed by a wired module 101 (where connection to a wired network would be used instead of connection to a wireless network 102). Also as contemplated herein and illustrated in FIG. 2, the wording “module 101 sends a message 208” can also be considered equivalent to “server 105 receives a message 208”. Likewise, the wording “server 105 sends a response 209” can be considered equivalent to “module 101 receives a response 209”.
A wireless module 101 can wake from a dormant state in order perform (i) remote and automated monitoring and (ii) control functions such as, but not limited to, collecting a sensor 101f measurement, communicating with server 105, and controlling an actuator 101y. If module 101 is connected to land-line power or a long-lasting external power source such solar power, then module 101 may remain in an active state and bypass a dormant state, although transmitting RF signals 201 may preferably only be utilized when communicating with wireless network 102 or sending data to and receiving data from wireless network 102 and/or M2M service provider 108. The wireless module 101 can acquire an IP address 202 from the wireless network 102. IP address 202 is illustrated as being an IPv6 address, but IP address 202 could also be an IPv4 address.
In order to transmit or send data from wireless module 101 to server 105, a wireless module 101 can use module program 101i to collect data from a sensor 101f in order to update server 105. Module program 101i can request a port number 203 from operating system 101h in order to have a source IP:port for sending data using IP protocols such as, but not limited to, TCP and UDP. The terminology “IP:port” as described herein refers to combining an IP address with a port number. Wireless module IP address 202 and port number 203 can be combined to form IP:port number 204. IP:port number 204 can be utilized as a source IP:port number for packets transmitted from wireless module 101, as well as a destination IP:port number for packets received by wireless module 101, when communicating with server 105.
In order to utilize IP Network 107, module 101 may also need a destination IP address and port number in order to send packets to server 105. Before sending data to server 105, wireless module 101 preferably retrieves server IP address 106 and server port number 205 from RAM 101e. Server IP address 106 could be recorded in RAM 101e via (i) a DNS query using server name 206 or (ii) queries to M2M service provider 108 or wireless network 102. CPU 101b may copy server IP address 106 and server port number 205 from nonvolatile memory into volatile memory such as, but not limited to, a register for processing to send a packet to server 105. Server name 206 could also be a server identity. (A) Server IP address 106 or server name 206 and (B) server port number 205 could be recorded in a nonvolatile memory such as, but not limited to, flash memory 101w and/or an eUICC 163 so that wireless module 101 can store the proper destination of packets transmitted or sent even when wireless module is dormant or shutdown. Server IP address 106 and server port number 205 can be combined into a server IP:port number 207.
After collecting data from a sensor, module 101 can send a packet from IP:port 204 to IP:port 207, and the packet could comprise a message 208 that may include the data from a sensor 101f. Note that message 208 does not need to include sensor data, and message could potentially be a periodic registration message or keep-alive message. As contemplated herein, the term “sensor measurement” can refer to data associated with or derived from a sensor 101f. A sensor measurement, can comprise a string containing data regarding a parameter of a monitored unit 119 and collected by a sensor 101f. The sensor measurement as sent in a message 208 can also represent a string (alphanumeric, binary, text, hexadecimal, etc.), where the string comprises a transformation or processing of sensor data collected by a CPU 101b, such including formatting, compressing, or encrypting, encoding, etc. of sensor data. A “sensor measurement” could comprise a plurality of data from a sensor 101f. 
In order to minimize bandwidth and time required for RF signals 201 to be active, module 101 can send the message 208 as a single UDP datagram in accordance with a preferred exemplary embodiment. The single UDP datagram in this embodiment can preferably be the only packet sent from module 101 to server 105 or M2M service provider 108 during a wake state for the module 101 when the radio 101z is active and transmitting, such as, but not limited to, in a radio resource control (RRC) connected state. In other words, according to this preferred exemplary embodiment, the message 208 sent by module 101 can preferably be the only message or packet sent by the wireless module to the server 105 between dormant periods of module 101. By sending message 208 as a single UDP datagram, both a battery 101k is conserved and utilization of valuable RF spectrum is reduced. Message 208 could also comprise a series of associated UDP messages.
Also, as contemplated herein, message 208 could comprise a related series of packets, so that message 208 could comprise multiple datagrams. As one example, if TCP is utilized as the transport protocol for message 208, then the series of TCP messages including the initial handshake, one or more packets of payload data, and the closing of the connection could together comprise message 208. As another example, if UDP or UDP Lite is utilized for the transport protocol, and payload data exceeds a maximum transmission unit (MTU) size for the UDP packet and the payload data is spread across multiple packets, then the multiple packets would comprise a message 208. Further, a related series of packets comprising a message 208 could be identified by using the same source IP:port number as either (i) received by server 105 or (ii) sent by module 101. In addition, a related series of packets comprising a first message 208 could be identified as a series of packets sent by module 101 before receiving a response 209 from a server that includes a module instruction 502 (depicted and described in connection with FIG. 5a below), and packets sent after receiving a response 209 could comprise a second message 208. Other possibilities for a message 208 to comprise multiple packets or datagrams may exist without departing from the scope of the present invention.
The UDP datagram for message 208 could also be formatted according to the UDP Lite protocol, as specified in IETF RFC 3828, which is also incorporated by reference herein. The term “UDP Lite” described in the present invention may also refer to any connectionless protocol widely supported on IP Network 107 where checksums may be partially disabled, thereby supporting the transfer of bit errors within a datagram. The advantages of UDP over TCP is that UDP can be quickly sent, while TCP requires a “handshake” with the server which requires more time and bandwidth, which would utilize more energy from battery 101k. According to an exemplary embodiment, both message 208 and response 209 can be TCP messages. In this exemplary embodiment, message 208 and response 209 could each comprise a series of TCP messages that can include a TCP SYN, SYN ACK, ACK, ACK w/ data, FIN ACK, etc.
According to an exemplary embodiment, module 101 sends (and server 105 receives) the same sensor data in multiple copies of the same UDP packet. Each of the multiple copies of the same UDP packet can also optionally be formatted according to the UDP Lite protocol. As one example, wireless module sends three identical copies of the UDP or UDP Lite packet that include the same sensor data. The benefit of sending three copies of UDP Lite include (i) the RF signals 201 received by the base station 103 could include bit errors, which could result in a regular (RFC 768) UDP packet being dropped, since a bit error could result in a UDP checksum mismatch, as received and processed by wireless network 102. Note that the use of checksums is mandatory in IPv6, and thus checksums cannot be fully disabled in IPv6. With UDP Lite packets transmitted by wireless module 101, where the mandatory checksum for IPv6 can cover the packet header, wireless network 102 can forward all packets received, potentially including bit errors, to server 105 over the IP Network 107.
Server 105 can receive the multiple copies of the UDP or UDP Lite packets, which could include bit errors received, and server 105 could compare or combine the multiple copies or each individual UDP Lite packet in order to remove bit errors. Note that UDP Lite is not required, and wireless module 101 could send the message 208 using a single UDP packet, or multiple copies of a regular UDP (i.e. non UDP Lite) packet. However, using UDP Lite with multiple packets sent can provide benefits such as if the sensor data is encrypted in the packet, then a single bit error would normally break the receiver's ability to decipher the data using a cryptographic key, unless the encrypted data was channel coded and the channel coding could recover from the bit error in order to present an error-free input of the encrypted data to a deciphering algorithm.
Further, between periods of sleep when a wireless module 101 becomes active and transmits RF signals 201, module 101, which may also comprise a wireless module 101, could send the sensor data in a single UDP Lite packet where the packet includes channel coding, which can also be referred to forward error correction. Forward error correction could also be implemented by sending multiple copies of the same UDP packet. Note that since large segments of message 208 could include encrypted or hashed data, those segments may not be appropriate for compression since the data is often similar to random strings which are not readily compressed. Channel coding techniques for the data in message 208 could include block codes and convolution codes. Block codes could include Reed-Solomon, Golay, BCH, Hamming, and turbo codes. According to a preferred exemplary embodiment, data within message 208 is sent as a UDP Lite packet using a turbo code to correct multiple bit errors within a packet or datagram sent by module 101 and received by server 105.
In system 200 illustrated in FIG. 2, server 105 can use IP:port 207 to receive the packet from wireless module 101 and sent from source IP:port 204 to IP:port 207, and the packet could comprise a message 208 that may include the data from a sensor associated with module 101 or monitored unit 119. As contemplated herein, a message 208 illustrated in FIG. 2 does not need to include sensor data and other data could be transmitted or sent, such as, but not limited to, a server instruction 414 (described in FIG. 4 below), or other data pertaining to module 101 or a monitored unit 119. Note that server 105 can use IP:port 207 to receive a plurality of messages 208 from a plurality of wireless modules 101. Server 105 preferably listens for UDP packets on IP:port 207 or monitors IP:port 207, although TCP packets could be supported as well. If server 105 receives multiple copies of the same UDP packet from module 101, server 105 preferably includes a timer to drop duplicate packets received outside a timer window such as, but not limited to, an exemplary 5 seconds.
After receiving the message 208 and processing the message according to the techniques described below such as, but not limited to, in FIG. 4, server 105 can send a response 209. Since module 101 may belong to a wireless network 102 which includes a firewall 104, the source IP:port of the message 208 received by server 105 could be different from the source IP:port 204 utilized by wireless module 101. The source IP:port in message 208 could be changed if firewall 104 performs network address translation (NAT), as one example. Server 105 may not readily know if a NAT translation has been performed on the message 208. Alternatively, firewall 104 may not perform NAT, but could still block data from the IP Network 107 which does not properly match the firewall rules. As one example, firewall 104 could be a symmetric firewall (but without NAT functionality), where only packets from IP:port 207 to IP:port 204 are allowed to pass the firewall after message 208 has been sent by module 101.
In either case, where firewall 104 may or may not perform NAT routing, server 105 preferably sends the response 209 from the server IP:port 207 to the source IP:port it receives in message 208. According to a preferred exemplary embodiment, response 209 is a UDP packet sent from server 105 with (i) a source IP:port 207 and (ii) a destination IP:port equal to the source IP:port received in message 208, as illustrated in packet 209a. The example use of source and destination IP:ports in message 208 and response 209 are also illustrated in FIG. 6a below. In this manner, the UDP packet can traverse a firewall 104, if firewall 104 is present. If firewall 104 is present and performs NAT routing, then firewall 104 can receive the response 209 and change the destination IP address and port within response 209 to equal IP:port 204.
According to exemplary preferred embodiments, module 101 may also obtain power from a land-line source, such as, but not limited to, a traditional 120 volt wall socket, or possibly power over Ethernet, and other non-transient power sources could be utilized as well. In this case, module 101 may remain persistently connected to the Internet through either a wireless network 102 or a wired connection such as, but not limited to, Ethernet. In other words, module 101 may omit entering periods of sleep or dormancy where inbound packets from the Internet would not be received due to the sleep state of module 101. Consequently in an exemplary embodiment, module 101, which does not sleep for periods longer than a minute, may preferably periodically send a firewall port binding packet 211 from IP:port 204 to IP:port 207 in order to keep ports and addresses within a firewall 104 and/or firewall 124 open to communications between module 101 and server 105. Firewall port binding packet 211 can comprise a packet that is sent periodically using a timer interval that is shorter than the port-binding timeout period 117 on a firewall 104 and firewall 124.
Continuing with this exemplary embodiment where module 101 does not sleep for periods longer than approximately one minute, if UDP is utilized for message 208 and response 209, then a small UDP packet comprising firewall port binding packet 211 can be sent periodically such as, but not limited to, every 45 seconds. If TCP is utilized for message 208 and response 209, then a small TCP packet comprising firewall port binding packet 211 can be sent periodically such as, but not limited to, every 4 minutes. Other possibilities for the timing of sending firewall port binding packet 211 are possible as well. By sending firewall port binding packet 211 periodically, server 105 can send module 101a response 209, (i) which could include a module instruction 502 as explained in FIG. 5a, at (ii) time intervals between message 208 and response 209 that are longer than the firewall port binding timeout values 117 of firewall 104 and/or firewall 124. Without firewall port binding packet 211, if (A) a response 209 sent from server 105 at an exemplary 180 seconds after receiving message 208, such as, but not limited to, after a firewall port binding timeout value 117 of firewall 104 of an exemplary 60 seconds transpired, then (B) response 209 would be dropped by firewall 104 and the response 209 would not be received by module 101.
FIG. 3
FIG. 3 is a flow chart illustrating exemplary steps for a module to send sensor data to a server, in accordance with exemplary embodiments. As illustrated in FIG. 3, FIG. 3 may include the data reporting steps 101x used by a module 101 in a module program 101i, where data reporting steps 101x and a module program 101i are depicted and described in connection with FIG. 1b above. The processes and operations, including data reporting steps 101x, described below with respect to all of the logic flow diagrams may include the manipulation of signals by a processor and the maintenance of these signals within data structures resident in one or more memory storage devices. For the purposes of this discussion, a process can be generally conceived to be a sequence of computer-executed steps leading to a desired result.
These steps usually require physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical, magnetic, or optical signals capable of being stored, transferred, combined, compared, or otherwise manipulated. It is convention for those skilled in the art to refer to representations of these signals as bits, bytes, words, information, elements, symbols, characters, numbers, points, data, entries, objects, images, files, or the like. It should be kept in mind, however, that these and similar terms are associated with appropriate physical quantities for computer operations, and that these terms are merely conventional labels applied to physical quantities that exist within and during operation of the computer.
It should also be understood that manipulations within the computer are often referred to in terms such as listing, creating, adding, calculating, comparing, moving, receiving, determining, configuring, identifying, populating, loading, performing, executing, storing etc. that are often associated with manual operations performed by a human operator. The operations described herein can be machine operations performed in conjunction with various input provided by a human operator or user that interacts with the computer.
In addition, it should be understood that the programs, processes, methods, etc. described herein are not related or limited to any particular computer or apparatus. Rather, various types of general purpose machines may be used with the following process in accordance with the teachings described herein.
The present invention may comprise a computer program or hardware or a combination thereof which embodies the functions described herein and illustrated in the appended flow charts. However, it should be apparent that there could be many different ways of implementing the invention in computer programming or hardware design, and the invention should not be construed as limited to any one set of computer program instructions.
Further, a skilled programmer would be able to write such a computer program or identify the appropriate hardware circuits to implement the disclosed invention without difficulty based on the flow charts and associated description in the application text, for example. Therefore, disclosure of a particular set of program code instructions or detailed hardware devices is not considered necessary for an adequate understanding of how to make and use the invention. The inventive functionality of the claimed computer implemented processes will be explained in more detail in the following description in conjunction with the remaining Figures illustrating other process flows.
Further, certain steps in the processes or process flow described in all of the logic flow diagrams below must naturally precede others for the present invention to function as described. However, the present invention is not limited to the order of the steps described if such order or sequence does not alter the functionality of the present invention. That is, it is recognized that some steps may be performed before, after, or in parallel other steps without departing from the scope and spirit of the present invention.
The processes, operations, and steps performed by the hardware and software described in this document usually include the manipulation of signals by a CPU or remote server and the maintenance of these signals within data structures resident in one or more of the local or remote memory storage devices. Such data structures impose a physical organization upon the collection of data stored within a memory storage device and represent specific electrical or magnetic elements. These symbolic representations are the means used by those skilled in the art of computer programming and computer construction to most effectively convey teachings and discoveries to others skilled in the art.
At step 301, before final distribution of the module to a sales channel, equipment distributors, or end users, an initial module private key 112b and a module identity 110 could be recorded in non-volatile memory 101w of the module 101. The initial module private key 112b could be a private key formatted according to the X.500 series of standards published by the International Organization for Standardization (ISO) in ISO/IEC 9594 or similar and subsequent standards, or alternatively according to another format including a propriety format. The initial module private key 112b could be formatted using RSA encryption algorithms or ECC encryption algorithms, and other possibilities exist as well for the format of encryption and/or decryption keys without departing from the scope of the present invention. Note that step 301 contemplates an alternative to the case where a module 101 derives its own public and private keys using key pair generation algorithms 141e. Thus, the present invention also contemplates that a module private key 112 is derived outside module 101 and loaded into nonvolatile memory 101w. Note that in this case, where an initial module private key 112b is loaded from an external source to module 101, that module 101 could still utilize other features contemplated herein, such as if module 101 needed to derive public and private keys in the future after the initial step 301.
Module identity 110 can be a unique identifier associated with module 101, and can represent a number or a string. The module private key 112 and module identity 110 could be recorded in non-volatile memory 101w by the manufacturer, or a service provider. Alternatively, the module private key 112 and module identity 110 could be recorded in non-volatile memory 101c by the end users. At step 302, the module is distributed and installed in physical proximity to a monitored unit 119. Although step 301 is illustrated as occurring before step 302 according to an exemplary embodiment, step 301 can take place after step 302 or concurrently with step 302, and other possibilities exist as well without departing from the scope of the present invention.
After installation of the module 101, module 101 can wake from a dormant state in step 303. The dormant state can comprise a state of low power usage as described in FIG. 1c, in order to conserve battery life and wired bandwidth or wireless spectrum resources. As noted in FIG. 1c, module 101 can utilize a bootloader program 125 in order to initiate operations from a sleep or dormant state. At step 303, the module private key 112b, module identity 110, server identity 206, and/or server address 106 could be moved from non-volatile memory 101w into RAM 101e. At step 304, the module 101 can read the module private key 112b and module identity 110 recorded in RAM 101e, and also record the server public key 114 and server IP:port 207. The server public key 114 and server IP:port 207 could also be either locally stored previous to step 304 in a non-volatile memory 101w, or obtained through the IP Network 107 via a query to M2M service provider 108. As one example, module 101 could obtain the server public key 114 by establishing an Internet connection through a network such as a wireless network 102 and downloading the server public key 114 from server 105.
If module 101 utilizes a sleep or dormant state (according to exemplary sleep or dormant states depicted and described in connection with FIG. 1c of U.S. patent application Ser. No. 14/023,181, which is herein incorporated by reference) in order to conserve power consumption or energy utilization, then according to a preferred exemplary embodiment at step 304, after waking, module 101 can preferably read from nonvolatile such as a flash memory 101w each of (i) module private key 112b, (ii) module identity 110, (iii) the server public key 114, (iv) server IP:port 207, and (v) data reporting steps 101x. The location of server 105 could be obtained via a DNS query using the server identity 206. Although not depicted in FIG. 3, server identity 206 and server IP:port 207 could also be recorded in non-volatile memory at step 301. Other means are possible as well for module 101 to obtain server public key 114 and server IP:port 207.
At step 305, the module 101 can read data from a sensor 101f. The data can comprise information regarding a monitored unit 119, as illustrated in FIG. 1a. As referenced herein, the data collected at step 305 may comprise a sensor measurement 305 or sensor data 305. At step 306, the module can utilize cryptographic algorithms 141 to (i) encrypt the data from sensor 101f using the server public key 114 and (ii) sign the encrypted data using the module private key 112b. Note that a symmetric ciphering algorithm 141b may be used at step 306, but since the symmetric key 127 may be derived using the server public key 114, the sensor data 305 can be encrypted using the server public key (indirectly) at step 306. According to a preferred exemplary embodiment, the module can add channel coding to the data resulting from the steps taken in the previous sentence, although the channel coding can optionally be omitted. A more detailed description of the steps for encrypting and signing data from the sensor are included in FIG. 4a below.
After encrypting and signing sensor data, the module can send the data to the server 105 in message 208, where message 208 is formatted and sent according to a either a TCP or UDP packet. An exemplary format of message 208 is also depicted and described in connection with FIG. 6 below. Message 208 could be sent using the UDP Lite protocol, although the message could also be sent in a TCP datagram, after completing the initial TCP “handshakes” with server 105. Message 208 in the form of a UDP or TCP datagram can be sent from the module IP:port 204 to the server IP:port 207. Message 208 can also comprise sending the sensor data in multiple datagrams, including two or more copies of the same data. Although not depicted in FIG. 3, upon the first communication with a server 105, according to an exemplary embodiment, module 101 can send a certificate 122 to server 105, where certificate 122 would normally include module public key 111. Server 105 could utilize a certificate 122 to verify a module identity 110.
As illustrated in FIG. 3, the module 101 can then receive reply from server 105 to the message 208 in the form of a response 209. Response 209 can be encrypted using the module public key 111 and signed with the server private key 105c, as depicted and described in connection with FIG. 5a below. An exemplary format of the response 209 is also depicted and described in connection with FIG. 6 below. The module 101 can receive the encrypted response 209 to message 208 in a datagram 209a that is sent from server IP:port 207 and received at module IP:port 204.
At step 307a, the module 101 can process the response 209 by decrypting the response 209 using the module private key 112b and cryptographic algorithms 141. At step 307b, module 101 can verify a digital signature of response 209 using the server public key 114 and cryptographic algorithms 141. Additional details regarding step 307a and 307b are depicted and described in connection with FIG. 5a below. Note that encryption of response 209 may be optionally omitted and a digital signature in response 209 may also be optionally omitted. Although not shown in FIG. 3a, if the module 101 cannot decrypt the response 209 or verify the digital signature of response 209, then the module 101 can drop the response 209 and optionally send message 208 again.
After the module 101 successfully processes response 209 in steps 307a and 307b, as shown in step 308, the module 101 can sleep the CPU 101b and/or shutdown the radio 101z. Step 308 could comprise the module 101 entering the “radio off” state 505a as depicted and described in connection with FIG. 6b of U.S. patent application Ser. No. 14/023,181 (the contents of which are hereby incorporated by reference in their entirety), and/or entering the “CPU off” state 505b as described in FIG. 6c of U.S. patent application Ser. No. 14/023,181. Step 308 could also comprise the module 101 sending a detach message to a wireless network 102 as depicted and described in connection with FIG. 5c below. Thus, according to a preferred exemplary embodiment, module 101 can omit sending or receiving any further radio resource control messages after processing the encrypted and/or signed response 209, when completing step 308 (until further radio resource control messages are processed after waking from a sleep state).
After entering the sleep state in step 308, the module can then periodically check a sleep timer at step 309, and wake from sleep if the timer has expired and report subsequent data from a sensor 101f to a server 105 by returning to step 305.
FIG. 4
FIG. 4 a is a flow chart illustrating exemplary steps for a module to process a message, including encrypting sensor data and sending a digital signature, in accordance with exemplary embodiments. The steps illustrated in FIG. 4 may comprise step 306 illustrated in FIG. 3 above. Since message 208 and response 209 may traverse the wireless network 102 and IP Network 107, according to an exemplary preferred embodiment, a module 101 and a server 105 can take additional steps in order to maintain security of a system 100, system 200, and related systems. Since module 101 could connect from a wide variety of networks, such as LAN, wireless LAN, wireless WAN, etc., server 105 may optionally support module 101 connecting from any valid IP address, including addresses outside of a mobile network operator's 108 wireless network 102. Module 101 can process a message 208 using the sequence of steps illustrated in FIG. 4. For additional clarification, an exemplary format of a message 208, using the exemplary steps of FIG. 4, is illustrated in FIG. 6 below. Note that the security methods described herein are optional, and message 208 and response 208 can be sent without the additional security steps described herein, but the use of these security steps may be preferred. FIG. 4 can contain the messages and steps shown within step 306 of FIG. 3, where a module 101 processes message 208 before sending it to server 105 through the wireless network 102 and IP Network 107.
As illustrated in FIG. 4, in preparing a message 208 to send to server 105, module 101 can utilize a sensor measurement 305, where the sensor measurement 305 comprises sensor data acquired by a sensor 101f associated with module 101. A sensor measurement 305 is also depicted and described in connection with FIG. 1c above, and may comprise a string or number containing data regarding a parameter of a monitored unit 119. Sensor measurement 305 can also comprise a plurality of measurements or processed sensor measurements 305 such as an average value over time, high and low values, etc. Sensor measurement 305 could be either raw or processed data collected by a sensor 101f. As illustrated in FIG. 4, module 101 could also include a server instruction 414, which could be a command for server 105 such as an update, query, or notification. A server instruction 414 could also be used by module 101 as input into step 402 below, where the server instruction 414 can be encrypted.
Module 101 may optionally add a security token 401, which could also be a random number, or a randomly generated text, binary, or hexadecimal string. Security token 401 could be created using random number generator 128 and included in message 208 in order to make each message 208 unique and thus avoid any replay attacks when message 208 traverses wireless network 102 and IP Network 107 in order to securely reach server 105. A random number in security token 401 could be processed by module 101 using a seed 128b in a random number generator 128, where the seed utilizes data from sensor 101f as input into the seed, as illustrated in FIG. 1c above. Security token 401 could alternatively be a non-random number used to make message 208 unique, such as a timestamp with significant digits to milliseconds or microseconds, and other possibilities for security token 401 exist as well. In other words, the use of security token 401 can ensure to a high level of certainty that each message 208 will be different and thus the same data within message 208 would not be sent more than once (other than a short timeframe such as within a few seconds where the same UDP packet for a message 208 could be intentionally sent more than once in order to implement and support forward error correction).
At step 401a, if (i) module 101 is sending message 208 to server 105 for the first time, or (ii) expiration time 133 for a previous symmetric key 127 has transpired, then module 101 may preferably include a symmetric key 127 within message 208, where the symmetric key 127 would be encrypted using an asymmetric ciphering algorithm 141a with the module private key 112 at step 402. In this case of (i) or (ii) in the previous sentence, module 101 can securely send the symmetric key 127 to server 105, which could then utilize symmetric key 127 in a symmetric ciphering algorithms 141b at later steps. As noted in FIG. 1 d, symmetric key 127 could be derived using cryptographic algorithms 141 and a random number from random number generator 128. If (a) module 101 has already sent a message 208 to server 105, or (b) expiration time 133 for a symmetric key 127 has not transpired (and thus symmetric key 127 would remain valid), then module 101 can omit including symmetric key 127 at step 401a. 
At step 402, module 101 could utilize the sensor data 305, security token 401, server public key 114, server instruction 414 and the cryptographic algorithms 141 to encrypt the sensor data 305 and security token 401. A step 402 could utilize either a symmetric ciphering algorithm 141b with a symmetric key 127 or an asymmetric ciphering algorithm 141a with the server public key 114. Symmetric ciphering 141b may be used to encrypt sensor data 305, and asymmetric ciphering 141a may be used to encrypt a symmetric key 127. The output of step 402 can be module encrypted data 403. If a symmetric key 127 is included within message 208, then module 101 preferably utilizes asymmetric ciphering 141a with server public key 114 at step 402. The asymmetric ciphering 141a at step 402 may be processed according to RSA algorithms 153, elliptic curve cryptography (ECC) algorithms 154, or other asymmetric ciphering algorithms for either public key cryptography or proprietary methods.
Note that if (A) a symmetric key 127 is utilized for symmetric ciphering 141b between module 101 and server 105 at step 402, such utilizing as a symmetric key 127 which could be derived using ECDH 159, then (B) AES 155, Triple DES, or other symmetric ciphering algorithms 141b can be used at step 402 to generate module encrypted data 403. If symmetric ciphering 141b is utilized in step 402, exemplary symmetric ciphers AES 155 and Triple DES are depicted and described in connection with FIG. 1d above. If symmetric ciphering 141b with ECIES is utilized in step 402, then step 402 could utilize the steps outlined in FIG. 2, titled “ECIES Encryption Functional Diagram” in “A Survey of the Elliptic Curve Integrated Encryption Scheme” by Martinez et al in the Journal of Computer Science and Engineering, Volume 2, August 2010, page 10, (herein incorporated by reference). The use of (i) symmetric ciphering algorithms 141b, such as with AES 155, Triple DES, and similar secure symmetric ciphers, with (ii) symmetric key 127 may be preferred at step 402, if symmetric key 127 is available.
After processing module encrypted data 403, module 101 can add or append a module identity 110. Module identity 110 is illustrated in FIG. 4 as being added after the module 101 processes module encrypted data 403, although module identity 110 may optionally only be included in module encrypted data 403 if symmetric ciphering 141b with cryptographic algorithms 141 and symmetric key 127 is utilized, (i.e. module identity 110 could be included before step 402, where module identity could be included as an input into step 402 as opposed to being added after step 402). By including module identity 110, possibly in the form of an encrypted module identity 110a, as external to module encrypted data 403 as illustrated in FIG. 4 at step 404, server 105 can use the module identity 110 to pre-process or route a message before decrypting module encrypted data 403. For example, server 105 could utilize a message preprocessor 105y and module identity 110 outside of module encrypted data 403 to select a sub-server 105w. By including module identity 110, possibly in the form of an encrypted module identity 110a, as external to module encrypted data 403, server 105 can use the module identity 110 to select either (i) a module public key 111 or (ii) a symmetric key 127 from a database 105k in order to decrypt module encrypted data 403 or verify a digital signature. The exemplary message 208 illustrated in FIG. 6 below shows one example of a message 208 where module identity 110 in the form of an encrypted module identity 110a is included as external to module encrypted data 403, which is also illustrated in FIG. 4.
Module identity 110 in a message 208 can represent the use of multiple unique strings or numbers over time that are uniquely associated with module 101, such as a first string for module identity 110 as recorded by module 101 and a second string for module identity 110 as recorded by a server 105. Module identity 110 could also comprise a session identifier, where the session identifier is uniquely associated with module identity 110 for a limited period of time, and a new session identifier is periodically generated by either module 101 or server 105. Thus, the use of a module identity 110 in a message 208 may comprise a different format or string than the module identity 110 preferably read from hardware, where the module identity 110 read from hardware could be a serial number, Ethernet MAC address, IMEI, etc. However, both can be utilized to uniquely identify a module 101 and thus are referred to herein as a “module identity” 110.
For cases where module 101 either (i) uses asymmetric ciphering 141a in a step 402, such as sending a symmetric key 127, or (ii) sends data without symmetric ciphering 141b (i.e. sends plaintext) module 101 can generate a module digital signature 405 for the message 208 using the module private key 112. The module digital signature 405 can be processed according to public key infrastructure (PKI) standards such as the National Institute of Standards (NIST) “FIPS 186-4: Digital Signature Standard” (which is hereby incorporated herein by reference), or IETF RFC 6979 titled “Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)” (which is hereby incorporated herein by reference). The use of a module digital signature 405 can be processed according to the description of a digital signature according to the Wikipedia entry for “Digital Signature” as of Sep. 9, 2013, which is incorporated by reference herein in its entirety. Module digital signature 405 may also comprise a Message Authentication Code (MAC) or tag. Also note that other uses of a digital signature as contemplated within the present invention may refer to the above three references and related standard techniques for processing and creating digital signatures.
Other PKI standards or proprietary methods for securely generating a module digital signature 405 may be utilized as well. According to a preferred exemplary embodiment, ECC algorithms for generating module digital signature 405 may be utilized in order to minimize the key length compared to RSA algorithms. Module digital signature 405 may comprise a secure hash signature using a secure hash algorithm 141c related to the secure hash algorithm 1 (SHA-1), or subsequent standards such as SHA-2 156 and SHA-3 157, and other possibilities exist as well. Module digital signature 405 is illustrated in FIG. 4 as being processed after module encrypted data 403, but module digital signature 405 may also optionally be included in module encrypted data 403. However, since module digital signature 403 can represent a secured hash signature that can contain limited useful information to a potential eavesdropper, module processing resources and energy can be conserved by including module digital signature 405 after and external to module encrypted data 403 (i.e. the benefits of encrypting module digital signature 405 may be limited). Also note that module digital signature 405 and the other secure digital signatures contemplated herein may be calculated with input from either (i) the plaintext in an encrypted message such as module encrypted data 403 or (ii) the ciphered data before conversion to plaintext, such as module encrypted data 403 before decryption at step 413. For embodiments where a symmetric key 127 and a symmetric ciphering algorithm 141b are used by module 101 to process module encrypted data 403, then a module digital signature 405 can be optionally omitted, since identity or authentication between module 101 and server 105 could be completed in the steps to establish a symmetric key 127.
Module 101 can then continue processing message 208 by including channel coding 406. Channel coding techniques for channel coding 406 could include block codes and convolution codes. Block codes could include Reed-Solomon, Golay, BCH, Hamming, and turbo codes. According to a preferred exemplary embodiment, channel coding 406 can utilize a turbo code, so that server 105 can correct bit errors received by server 105 in message 208. Alternatively, module 101 could implement channel coding by simply transmitting the same packet more than once and the use of block codes or convolution codes could be bypassed. Or, module 101 could implement channel coding by both transmitting the same packet more than once and also using a block code or convolution code in the body of the packet. The use of channel coding 406 can be preferred, since any bit errors received by server 105 within module encrypted data 403 or module digital signature 405 in message 208 could break a decryption or signature verification algorithm such as cryptographic algorithms 141 used by server 105. Thus, the use of channel coding 406 (with a transport protocol that supports the transmission of bit errors such as UDP with checksums disabled in IPv4 or UDP Lite) can ensure the decryption of message 208 is robust to bit errors. Bit errors may potentially generated by intermediate network links and nodes as message 208 traverses a wireless network 102 or IP Network 107. Channel coding 406 may optionally be omitted.
As illustrated in FIG. 4, module 101 can then format message 208 according to a transport protocol such as UDP within UDP processing 407 to create message 208. Other options besides the UDP processing illustrated in FIG. 4 are available as well, including TCP formatting, but UDP formatting may be preferred in order to minimize the number of packets transmitted as well as TCP overhead. Note that TCP overhead when using IPv6 can be significant, since the full series of TCP messages to establish a TCP session and transmit the message 208 may include about 4-6 packets, where each packet in the message includes a TCP header and a full 128 bit address for both the source IP address and the destination IP address. In contrast, UDP may preferably require only a single packet for message 208 and a single packet for response 209, thus significantly reducing the overhead and conserving either (i) a battery 101k life or (ii) energy usage by module 101 by reducing the data transmitted and received by module 101.
According to a preferred exemplary embodiment, UDP formatting 407 can be formatted according to the UDP Lite protocol (IETF RFC 3828) with IPv6, whereby UDP checksums can be partially disabled and channel coding 406 can be included in the UDP datagram to correct for bit errors. Note that the UDP and UDP Lite protocols may be updated in the future with subsequent standards, but the UDP formatting 407 may preferably continue to include both (i) partially or fully omitted packet checksums within the packet header and (ii) channel coding within the packet body. Also note that if IPv4 is utilized by module 101 and server 105, regular UDP (i.e. according to RFC 768) formatting may be utilized with channel coding 406 and checksums in the packet header may be disabled.
As illustrated in FIG. 4, after adding UDP formatting 407, module 101 may record a fully formatted message 208. As illustrated in FIG. 2, message 208 can be sent by module 101 using a physical interface 101a such as radio 101z and a wireless network 102 and the IP Network 107. Additional details regarding the structure of message 208 after taking exemplary steps in FIG. 4 are shown in FIG. 6 below. The security and efficiency features of message 208 can be useful for module 101 to efficiently balance potentially competing priorities of conserving battery life/bandwidth utilization/energy while maintaining security.
FIG. 5a 
FIG. 5a a is a flow chart illustrating exemplary steps for a module to process a response from the server, including verifying a server's identity and decrypting instructions, in accordance with exemplary embodiments. Module 101 can perform the steps illustrated in FIG. 5a in order to securely and efficiently process a response 209 from server 105. The steps illustrated in FIG. 5b may comprise steps 307a and 307b illustrated in FIG. 3. Module 101 can receive response 209 using IP:port 204, as illustrated in FIG. 2. Response 209 can be formatted according to the UDP protocol or UDP Lite protocol, although other possibilities exist as well for the transport layer formatting of response 209, including TCP.
At step 407, module 101 can process the packet using the appropriate transport layer protocol, such as UDP. In this step 407, the body of the packet comprising response 209 can be extracted, and a checksum, if any, can be calculated to verify the integrity. An exemplary format of response 209 is depicted and described in connection with FIG. 6 below. Note that if the UDP Lite protocol is utilized, the checksum may optionally only apply to the packet header. At step 406, module 101 can process and remove channel coding, if channel coding is present in response 209. Note that if a wireless network 102 comprises a IEEE 802.15.4 network, then UDP Lite may preferably utilized, and UDP Lite may preferably be utilized if wireless network 102 is a PLMN mobile network and the PLMN mobile network supports UDP Lite protocol. Channel coding techniques utilized in step 406 could include block codes and convolution codes, and can use related algorithms as used in channel coding 406 in FIG. 4. By processing channel coding in step 406, module 101 can correct potential bit errors received in response 209. As noted above, the use of channel coding 406 can be preferred, since any bit errors received within server encrypted data 504 in response 209 could break (i) a cryptographic algorithms 141 used by module 101 at subsequent step 514, and/or (ii) the verification of a server digital signature 506 at step 501a. 
At step 501, module 101 can read and record the server identity 206. Server identity 206 may preferably be a string that is external to server encrypted data 504 within response 209, as illustrated in FIG. 6 below. The server identity 206 can preferably match a server identity 206 used in message 208. The server identity 206 could also comprise the source IP address 106 of response 209, or a domain name resolving to the source IP address 106, or a domain name associated with IP address 206. Server identity 206 may also be uniquely associated with an identity in the “Common Name” (CN) field of a certificate 122 for server 105. Receiving or processing a server identity within a response 206 may optionally be omitted, if module 101 can select the appropriate server public key 114 without first obtaining server identity 206. At step 501a, module 101 can validate and verify the server identity 206 using the server digital signature 506 inserted by server 105 in response 209. Server digital signature 506 can comprise a secure hash signature, where server 105 generated the hash signature using as input into a digital signature algorithms 141d (i) the server private key 105c and (ii) at least a portion of the server encrypted data 504. Module 101 can utilize the server public key 114 recorded in memory to securely validate the server digital signature 504, also by using digital signature algorithms 141d. 
The server digital signature 504 can be verified according to public key infrastructure (PKI) standards such as the National Institute of Standards (NIST) “FIPS 186-4: Digital Signature Standard”, or IETF RFC 6979 titled “Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)”. Other PKI standards or proprietary methods for securely verifying a server digital signature 504 may be utilized as well. Also, server digital signature 506 could optionally be included in server encrypted data 504, where step 501a could take place after step 505. But, since server digital signature 506 may comprise a secure hash signature, any benefits from ciphering the secure hash may be small while requiring additional processor resources.
Note that if module 101 had previously received server digital signature 506 in a previous response 209, then steps 501 and 502 may optionally be omitted within a subsequent response 209. In other words, after module 101 receives a valid server digital signature 504, server 105 may then transmit a subsequent server digital signature 506 periodically according to rules based upon the security requirements of the application. As one example, if (a) after sending a symmetric key 127 in a message 208 to server 105 and receiving a response 209 to the message 208 with (i) a valid server digital signature 506 and (ii) a server encrypted data 503 using symmetric key 127, then (b) module 101 can subsequently have reasonable assurance that subsequent responses 209 using symmetric key 127 are also from server 105. According to a preferred exemplary embodiment, when module 101 sends a new symmetric key 127 using an asymmetric ciphering algorithms 141b, the response 209 from server 105 with server encrypted data 504 (where the server encrypted data 504 was created using the new symmetric key 127) can preferably include or be associated with a server digital signature 506 in either the response 209 or another packet from server 105.
Although not depicted in FIG. 5b, upon completing step 501a, module 101 may also optionally verify the server identity 206 of server 105 using a certificate 122 associated with server 105 and the public key of a certificate authority 118. Module 101 could request a certificate 122 associated with server 105 and calculate a secure hash signature 123 using cryptographic algorithms 141 and a certificate authority public key 131 (illustrated in FIG. 1a). Other possibilities exist as well for module 101 to verify the identity of server 105 without departing from the scope of the present invention. As one alternative, module 101 could utilize Domain Name System Security Extensions (DNSSEC), as specified in multiple IETF RFCs including RFC 4033, 4034, and 4035 to securely resolve server identity 206 into IP address 106. For example, module 101 could verify that the source IP address within response 209 matches a DNSSEC record for server name 206.
After verifying server digital signature 506 in step 501a, module 101 can record an authenticated server encrypted data 504 from server 105. Authenticated server encrypted data 504 may comprise an acknowledgement that server 105 received message 208. Authenticated server encrypted data 504 may be useful if the UDP or UDP Lite protocol is used to send message 208, since UDP is a connectionless protocol and module 101 may need confirmation that server 105 received message 208. Note that if steps 501 and 501a are omitted, then authenticated server encrypted data 504 may comprise a simple acknowledgement that server 105 received message 208. Although not depicted in FIG. 5a, if module 101 does not receive response 209 or server encrypted data 504 before a timer expires, such as within an exemplary duration of 2 seconds, then module 101 can resend message 208.
At step 505, module 101 can decrypt server encrypted data 504 using either (i) module private key 112 as a decryption key if asymmetric ciphering 141a is utilized to process server encrypted data 504, or (ii) symmetric key 127 if symmetric ciphering 141b is utilized to process server encrypted data 504. Module 101 can utilize cryptographic algorithms 141 and the key in order to decrypt the server encrypted data 504 at step 505. Module 101 can utilize techniques to decrypt server encrypted data 504 that are described in connection with creating module encrypted data 403 described in FIG. 4 above. If server encrypted data 504 uses an asymmetric ciphering, the cryptographic algorithms 141 used in step 505 may be processed according to RSA algorithms 153, elliptic curve cryptography (ECC) algorithms 154, or other algorithms for public key cryptography, as described previously herein. ECC algorithms 154 may be preferred with asymmetric ciphering in order to maintain high security with small key lengths, compared to RSA, in order to minimize the message lengths, radio frequency spectrum utilization, and processing power required by wireless module 101. If server encrypted data 504 uses symmetric ciphering 141b, the cryptographic algorithms 141 can use symmetric key 127 to decrypt server encrypted data 504 at step 505.
Module 101 and server 105 could utilize a pre-agreed protocol in order to select the use of asymmetric ciphering 141a or symmetric ciphering 141b in a response 209. According to an exemplary embodiment, module 101 and server 105 (i) utilize asymmetric ciphering 141a when transmitting symmetric keys 127 or other keys such as pre-shared secret keys, new private keys, etc., and (ii) utilize symmetric ciphering 141b at other times (i.e. when not sending/receiving a key). Since the exemplary response 209 illustrated in FIG. 6 does not contain a symmetric key, module 101 can utilize symmetric ciphering 141b in a step 505 with symmetric key 127 to decrypt server encrypted data 504 at step 505.
Response 209 may include a module instruction 502. By including module instruction 502 in server encrypted data 504 and response 209, the module instruction 502 can be read and processed by device 101 at step 507, after the server encrypted data 504 is decrypted at step 505. Module 101 can subsequently perform the module instruction 502 in step 507. Note that server encrypted data 504 may optionally include an acknowledgement that message 208 was received by server 105. In this manner, an “ACK” response to message 208 can be securely transmitted by server 105 and received by module 101. Additional details for exemplary module instruction 502 and the processing of a module instruction 502 by module 101 are depicted and described in connection with FIG. 4 of U.S. patent application Ser. No. 14/064,618, filed Oct. 28, 2013 in the name of John Nix, entitled “A Set of Servers for “Machine-to-Machine” Communications using Public Key Infrastructure,” which is hereby incorporated by reference in its entirety. Upon completion of the processing of response 209 illustrated in FIG. 5b, module 101 can perform functions such entering the sleep or dormant states illustrated at step 308 in FIG. 3a, thus conserving battery life (if present in module 101) or energy while maintaining a secure, robust, and highly scalable system 100.
FIG. 5b 
FIG. 5b is a flow chart illustrating exemplary steps for a module to communicate with a server after deriving a public key and private key, in accordance with exemplary embodiments. In order to utilize communications secured with PKI techniques such as, but not limited to, private keys, public keys, certificates, and identities, a module 101 may preferably obtain or generate these keys and utilize a module identity 110 and/or a certificate 122 in a secure manner. Given that a plurality of modules 101 may be deployed in potentially remote places, without frequent contact with end users or technicians, the use of secure PKI techniques for a module 101 can create a significant set of challenges for the generation of module public key 111 and module private key 112, as well as properly and securely obtaining a certificate 122 with an module identity 110. Using conventional technology, significant challenges and costs can be incurred when (i) module 101 has already been deployed, such as collecting data from a monitored unit 119, and (ii) module 101 needs to utilize a new set of module private key 112 and module public key 111.
Exemplary embodiments that include derivation or processing of a new module private key 112 and module public key 111 may utilize the particular steps and procedures contemplated herein, in order to minimize any potential human intervention (with related costs) while continuing to maintain or also enhance security, compared either (i) externally generating module private key 112, and/or (ii) continuing to use the same module private key 112 for the lifetime of module 101. Over a long period of operating time for a module 101, such as, but not limited to, several years or longer, there may be many reasons module 101 may need a new pair of PKI keys, such as, but not limited to, (i) expiration of a certificate 122, or the certificate 122 of a parent signature authority, (ii) the transfer of ownership or control of module 101, where the prior ownership could have direct or indirect access to the module private key 112, (iii) supporting a new server 105 that has different security requirements or a different set of cryptographic parameters 126 (longer keys, different ECC curves, different cryptographic algorithms 141, etc.), and/or (iv) revocation of a public key in a chain of signatures associated with a certificate 122. In the case of (ii) above, new ownership of module 101 may require a module 101 to utilize a new module private key 112 since the old ownership may have access to an old module private key 122. In the case of (iii) above, a new server 105 may require a pair of public/private keys incompatible with a prior set of public/private keys utilized by module 101 and/or a certificate 122 for module 101.
Other possibilities exist as well for reasons why a module 101 and/or server 105 may prefer for a module 101 to utilize a new module public key 111 and new module private key 112. In an exemplary embodiment, module 101 may generate a new public/private key periodically in order to enhance the security of a system 100. A benefit of a system 100 or system 200 supporting periodic generation of keys by module 101 is that the key length can be shortened in order to obtain a similar level of security, and the processing power and energy consumption, possibly from a battery 105k, can be reduced through the use of shorter key lengths. In other words, over time such as, but not limited to, several months or years, the use of a plurality of different pairs of public/private keys for module 101 with shorter key lengths can be both more secure and energy efficient than using a single pair of public/private keys with a longer key length for the lifetime of module 101. Shorter key lengths may also be more compatible with processing power constraints of a module 101. Thus, in exemplary embodiments, module 101 and/or server 105 may prefer for module 101 to periodically generate new public and private keys.
The general approach adopted by most mobile phone networks over the past two decades has been founded upon the use of a pre-shared secret key recorded in subscriber identity module (SIM) or UICC cards, such as the Ki pre-shared secret key in 2G, 3G, and subsequent networks. That approach may work for mobile phones, where the SIMs can often be easily replaced, but the use of a pre-shared secret key in a SIM or UICC may not be suitable for a module 101 and M2M service provider 108 for many circumstances. As one example, significant costs may be incurred by swapping out a SIM card for already deployed modules 101, especially if they are in remote locations or continually moving such as, but not limited to, a tracking device on a container, pallet, truck, or automobile. In an exemplary embodiment, a module 101 may preferably record multiple pairs of public/private keys 111/112 for various and different functions, such as, but not limited to, connecting to different servers 105, connecting to different wireless networks 102, etc. As contemplated herein, recording more than one public/private key 111/112 can comprise module 101 recording a plurality of pairs of module public keys 111 and module private keys 112. In exemplary embodiments, one pair comprising a first module public key 111 and a first module private key 112 can be identified or selected from a different pair comprising a second module public key 111 and a second module private key 112 using a module public key identity 111a. 
The number of pairs of public/private keys useful to a module 101 concurrently could be several, such as, but not limited to, an exemplary three or more actively used public/private keys, although other possibilities exist as well. Manually trying to change or add a new SIM card each time a new security key is required may not be efficient or feasible. Or in another exemplary embodiment, the multiple pairs of private and public keys could be used in sequence, such that module 101 with server 105 utilizes a single module public key 111 and module private key 112 at any given point in time. In the case where module 101 with a module identity 110 derives or generates more than one module private key 112 and module public key 111 during the lifetime of module 101 and sends the derived module public keys 111 over time to a set of servers 1010 (as illustrated in FIG. 10 below), this case may be considered module 101 sending a series of module public keys 111 for a module identity 110. The various pairs in the series may also use either different sets of cryptographic parameters 126 or the same set of cryptographic parameters 126. The series of module public keys 111 (with corresponding module private keys 112) can be processed by a CPU 101b with key pair generation algorithms 141e and a random number generator 128. The random number generator 128 can use input from a sensor 101f, a radio 101z, and/or a temporary random seed file 139.
In exemplary embodiments, module 101 can use a module public key 111 for sending a module encrypted data 403 or receiving a server encrypted data 504 by either (i) sending the module public key 111 to a server 105 in order to allow the module encrypted data 403 to be decrypted or the server encrypted data 504 to be encrypted, or (ii) inputting the module public key 111 into a key derivation function 141f in order to derive or process a derived shared secret key 129b, which could be used with a symmetric key 127. Other possibilities exist as well for module 101 to use its own module public key 111 with cryptographic algorithms for communicating with a server 105.
FIG. 5b illustrates exemplary steps that can be performed with module 101, including using a module program 101i, for generating, deriving, and/or updating a module public key 111 and module private key 112. The steps illustrated in FIG. 5b include both (i) an “initial” or “startup” case where module 101 has not previously derived keys (or keys not internally derived may not have been loaded), and (ii) a subsequent or “follow on” time where module 101 can generate or derive keys after keys were initially obtained or derived. Note that efficient and secure methods and systems contemplated herein, including in FIG. 5b, may also be utilized with a regular consumer mobile phone, or smartphone, as a module 101. Mobile phones as module 101 can benefit from (i) deriving a module public key 111 and a module private key 112, (ii) sending module encrypted data 403 in a message 208 using the derived keys, and (iii) receiving a server encrypted data 504 in a response 209 also using the derived keys. In the exemplary embodiment where module 101 comprises a mobile phone, then sensor 101f may comprise a microphone and actuator 101y may comprise a speaker, and other possibilities exist as well to those of ordinary skill in the art for module 101 to comprise a mobile phone.
At step 511, during manufacturing of module 101, including manufacturing of sub-components such as, but not limited to, a circuit board, assembly of hardware components illustrated in FIG. 1b, etc., a module identity 110 could be written into the hardware, and could comprise a serial number, International Mobile Equipment Identity (IMEI) number, Ethernet MAC address, or a similar persistent identification for a module 101. An IEMI number may be used with a mobile phone as module 101, in a preferred embodiment. For security purposes, the module identity 110 may preferably be written into a read-only location or protected location or protected memory, such as, but not limited to, a readable location on a system bus 101d, which could also comprise a ROM 101c. Recording and utilizing module identity 110 is also depicted and described in connection with FIG. 1c, FIG. 2, and elsewhere herein. Alternatively, module identity 110 could be recorded in a non-volatile memory such as, but not limited to, a flash memory 101w. 
At step 512, module 101 can be distributed to end users and also installed with a monitored unit 119. If module 101 is a mobile phone, then monitored unit 119 could be a person that carries the mobile phone. Also note that a monitored unit 119 could be omitted, and a module 101 could use the techniques contemplated herein. At step 513, a shared secret key 510, parameters 126, and a server address 207 can be recorded in a nonvolatile memory 101w. Parameters 126 may comprise settings for a cryptographic algorithms 141 as illustrated in FIG. 1 g, including (i) key lengths, (ii) algorithms to utilize for key generation or ciphering, such as, but not limited to, selecting RSA algorithms 153 or ECC algorithms 154, (iii) a specific secure hash algorithm 141c to utilize, such as, but not limited to, SHA-256 or SHA-3, (iv) an expiration date of the module public key 111, (v) a maximum time value for an expiration time 133 associated with a symmetric key 127, (vi) a ECC parameters 137 or an ECC standard curve 138 as parameters 126 in FIG. 1h of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, (vii) the specification of or values for a padding scheme for use with a digital signature algorithms 141d, and/or similar or related values for using cryptographic algorithms 141d. Although not depicted in FIG. 5b, at step 512 a configuration file could also be loaded into non-volatile memory, where the configuration file includes a plurality of fields specifying the operation of module 101. The shared secret key 510, parameters 126, and server address 207 could be included in a configuration file.
Continuing at step 513, server identity 206 could be utilized in place of or in addition to server address 207, and in this case module 101 can later perform a DNS or DNSSEC lookup using server identity 206 in order to obtain server address 207 for use in a message 208, such as the destination address. Shared secret key 510 and server address 207 (or server identity 206) could also be recorded in a ROM 101c at step 513. Step 513 may also be performed concurrently with step 511 or step 512. According to an exemplary embodiment, a manufacturer may perform step 513 and in this case step 513 could take place concurrently with step 511. In another embodiment, a distributor of module 101 could perform step 513 and in this case step 513 could take place concurrently with step 512. Alternatively, step 513 may be performed by a technician or end user after manufacturing and distribution and before module 101 begins collecting sensor data with a monitored unit. Other possibilities exist as well for the sequence of steps 511 through 513 illustrated in FIG. 5b without departing from the scope of the present invention.
Note that step 513 may take place multiple times during the lifetime of a module 101, and in this case (a) the first time step 513 is conducted, step 513 could be conducted concurrent with steps 511 or 512, and (b) a subsequent time step 513 is conducted, step 513 could be conducted after the receipt of a response 209, where the response 209 includes a second shared secret key 510, server address 207, and also potentially a new module identity 110. In other words, Although not depicted in FIG. 5b, a module 101 could return to step 513 from later steps upon the equivalent of a “factory reset”, or similar command where flash memory 101w and other nonvolatile memory would be cleared. In an exemplary embodiment where step 513 takes place a second time may potentially be the transfer of ownership or control of module 101, or a another embodiment where step 513 takes place a second time could be the upload of new firmware that is incompatible with a previous configuration file. In any case, shared secret key 510 can preferably be uniquely associated with module 101 (i.e. any given shared secret key 510 may belong only to an individual module 101).
Shared secret key 510 may comprise a pre-shared secret key 129a, as described in FIG. 1c. If module 101 has already derived a module private key 112 and module public key 111 (such as when step 513 is being conducted at a second or additional time as contemplated in the previous paragraph), then shared secret key 510 may comprise (i) a key received in a server encrypted data 504 including possibly a symmetric key 127, or (ii) a derived shared secret key 129b. Derived shared secret key 129b could be obtained from using a key derivation function 141f and module public key 111 and server public key 114, using a module public key 111 that has already been derived or used by module 101 (such as if at least one module private key 112 and module public key 111 had already been used or derived before step 513).
As contemplated herein in an exemplary embodiment, an first module private key 112 and first module public key 111 could be derived outside module 101 and loaded into a nonvolatile memory such as flash memory 101w at a prior time before step 513, and the shared secret key 510 could be received by module 101 using the first module private key 112 and module public key 111 (such as, but not limited to, receiving the shared secret key 510 in a server encrypted data 504 using the first module private key 112 which had been loaded). Step 513 could then comprise a later time after the server encrypted data 504 has been received that includes the shared secret key 510, where module 101 may (i) prefer to begin utilizing keys that module 101 internally derives using cryptographic algorithms 141 instead of (ii) continuing to use the first module public key 111 and module private key 112 that were derived outside of the module 101, such as, but not limited to, possibly loaded into a nonvolatile memory from an external source.
In the embodiment where shared secret key 510 has not been received by module 101 in a server encrypted data 504, shared secret key 510 could be obtained and loaded by a distributor, installer, or end user into a nonvolatile memory such as, but not limited to, flash memory 101w in the form of a pre-shared secret key 129a, where pre-shared secret key 129a was obtained using a module identity 110 and pre-shared secret key code 134 as depicted and described in connection with FIG. 1e of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix. Module 101 could also utilize a first pre-shared secret key 129a, including a first pre-shared secret key 129a entered by potentially a distributor, installer, or end-user described in FIG. 1c herein, to derive shared secret key 510. Other possibilities exist as well for shared secret key 510, and shared secret key 510 can be useful for the proper identification and/or authentication of module 101 upon module 101's generation of a private key 112 and public key 111, as described below including step 517. If module 101 is a mobile phone, as contemplated herein, shared secret key 510 could be loaded by a distributor or company selling or servicing the mobile phone, or shared secret key 510 could be obtained by the end user or subscriber accessing a web page associated with a mobile operator for a wireless network 102 associated with the mobile phone and/or SIM card.
Also note that as contemplated herein, an initial module private key 112b and initial module public key 111b could be recorded into nonvolatile memory at step 513. For example, a manufacturer, distributor, installer, technician, or end-user could load the initial module private key and initial module public key 111b, where the initial module public key 111b would be utilized to authenticate at step 517 a subsequent set of public/private keys derived by module 101 at step 515. In this case, the initial module public key 111b and/or initial module private key 112b described in the previous two sentences could comprise the shared secret key 510. In another embodiment, the initial module public key 111b and initial module private key 112 could be recorded in a SIM or UICC, and the SIM or UICC could be either virtual or physical such as, but not limited to, a SIM card, including a Universal Integrated Circuit Card (UICC) or an embedded UICC (eUICC) 163. A set of servers 1010 could also record the initial module public key 111b recorded in the SIM (including an eUICC 163), and the set of servers 1010 could authenticate a message or a subsequent module public key 111 derived by module 101 (such as in a step 515 below) using the initial module public key 111b. 
The use of an initial module public key 111b and/or initial module private key 112b are also depicted and described in connection with FIG. 5b of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety. Thus, FIG. 5b also contemplates an embodiment where shared secret key 510 at step 513 comprises an initial public/private key pair for module 101 that is not internally derived by module 101, including keys derived at step 515. Note that the contemplation of the use of shared secret key 510 as a pre-shared secret key 129a within the present invention may be different than the use of a pre-shared secret key within a subscriber identity module (SIM) card as commonly supported by wireless networks 102 with mobile phones in 2013.
If either a “virtual” SIM or a physical SIM card or eUICC 163 is present within module 101 (including a UICC or eUICC), and the SIM contains a pre-shared secret key, such as, but not limited to, Ki, then as contemplated herein, shared secret key 510 may be derived using the SIM and Ki. As one example, module 101 could (i) utilize a RAND message, potentially received from a 3G or 4G mobile network such as wireless network 102, and (ii) input the RAND into the SIM card and receive a response RES (or SRES), and utilize the string in RES to process or derive a shared secret key 510. Response RES could also comprise a shared secret key 510. Server 105 could also submit the same RAND associated with the SIM and Ki to wireless network 102, and receive the same RES as obtained by module 101. By both module 101 and server 105 having the same RES value, they can follow a pre-agreed series of steps to use the same RES in order to derive a commonly shared secret key 510 (or the shared RES could comprise a shared secret key 510). In one embodiment where module 101 includes a SIM for a wireless network 102, such as, but not limited to, a 4G LTE network, module 101 and server 105 could both utilize a key derivation function 141f, using the same RES as input, in order to derive the same shared secret key 510.
At step 514, module 101 can read module identity 110 using a read-only address. Module 101 can read module identity 110 directly from read-only hardware address by using system bus 101d, including from a ROM 101c, or module 101 can read module identity 110 from a nonvolatile memory such as a flash memory 101w. Step 514 could also take place after step 515 below. At Step 515, module 101 can derive module private key 112 and a corresponding module public key 111 using (i) random number generator 128, (ii) cryptographic parameters 126, (iii) cryptographic algorithms 141, and/or (iv) a key pair generation algorithm 141e. Module 101 at step 515 and elsewhere in the present invention can be a mobile phone such as, but not limited to, a smartphone. Private key 112 and corresponding module public key 111 can be derived according to a wide range of parameters 126, and can utilize different algorithms for different pairs of keys, such as, but not limited to, RSA 153 or ECC 154. Key derivation at step 515 could generate keys of various lengths, such as, but not limited to, 2048 bits with RSA 153 or 283 bits with ECC 154, and other possibilities exist as well. If using ECC 154 to derive a pair of keys for module 101, step 515 could also accommodate the use of different elliptic curves for compatibility with server 105, such as, but not limited to, the use of odd-characteristic curves, Koblitz curves, and making sure the derived keys by module 101 use a compatible or identical elliptic curve or defined elliptic curve equation as server 105, etc. Module 101 can use ECC parameters 137 or an ECC standard curve 138 in a parameters 126 to derive module private key 112 and/or module public key 111.
Deriving keys in step 515 could also comprise using values such as constants or variables in a set of cryptographic parameters 126 to define an elliptic curve equation for use with an ECC algorithm 154. The values or constants to define an equation for an elliptic curve could be input into a key pair generation algorithms 141e in the form of ECC parameters 137 or an ECC standard curve 138. In an exemplary embodiment, where a parameters 126 does not include constants and variables for defining an elliptic curve equation, a key pair generation algorithms 141e could use pre-defined elliptic curves with ECC algorithms 154 such as, but not limited to, standardized, named curves in ECC standard curve 138 including exemplary values such as, but not limited to, sect283k1, sect283r1, sect409k1, sect409r1, etc. Exemplary, standardized named curves, as opposed to module 101 and server 105 using an internally generated elliptic curve equation using cryptographic parameters 126, are also identified as example curves in IETF RFC 5480, titled “Elliptic Curve Cryptography Subject Public Key Information”. Thus, module 101 could use either standardized elliptic curves, or a separate defined elliptic curve equation as specified in a parameters 126.
The curve for module 101 to utilize in deriving module public key 111 and module private key 112 at step 515 could be specified in a set of cryptographic parameters 126. Consequently, the parameters of keys generated by module 101 at step 515 (including key length or algorithms utilized) may be selected based upon the requirements of the application and can be included in a parameters 126. When deriving keys at step 515, module 101 may also preferably utilize data from sensor 101f, radio 101z, a bus 101d, a physical interface 101a, memory 101e, and/or a clock 160 in order to generate a seed 128b for random number generator 128, or random number generator 128 could utilize these inputs directly. A random number 128a can be input into key pair generation algorithm 141e in order to derive the module public key 111 and module private key 112. Note that with ECC algorithms 154, a module private key 112 can be a random number 128a in one embodiment, and the module public key 111 can be derived with a key pair generation algorithms 141e using the module private key 112 comprising the random number 128a. 
Upon key derivation at step 515, module private key 112 and module public key 111 can be recorded in a nonvolatile memory 101w. Module private key 112 can preferably not be transmitted or sent outside module 101. Also note that over a potential lifetime of a decade or more of operation of module 101, each time a new module private key 112 may be required (for various potential reasons outlined above), the external recording and/or transferring of module private key 112 incurs a potential security risk. Security risks can be compounded if the external location records private keys 112 for a plurality of modules 101. Also, by internally generating private key 112 at step 515, module 101 can overcome significant limitations and costs requiring the distribution of a pre-shared secret key Ki in the form of a SIM card or similar physical distribution of a pre-shared secret key, after module 101 begins operations. In comparison, the use of a shared secret key 510 in the present invention does not require physical distribution of a new shared secret key 510 after module 101 begins operations. Module 101's key derivation could be triggered by either (i) a bootloader program 125, where the bootloader program 125 determines that memory within module 101 does not contain a module private key 112, or (ii) via a module instruction 502 such as, but not limited to, a “key generation” or “derive new keys” command in a response 209 from a server, and other possibilities exist as well.
Note that module 101's generation of keys after deployment and installation may create challenges for authentication of a new module public key 111 with module identity 110, since module 101 may be connecting to server 105 or M2M service provider 108 via the Internet 107. After module 101 creates new module public key 111 and module private key 112 at step 515, at step 516 server 105 can receive a message 208 with the module identity 110, the new module public key 111, and cryptographic parameters 126. Parameters 126 in message 208 at step 516 can represent the parameters 126 used to generate the module public key 111. The sub-steps for a server 105 to receive a message 208 are also depicted and described in connection with FIG. 2 and also FIG. 1c above. Parameters 126 within a message 208 can comprise descriptive values for new module public key 111. Note that at step 516, server 105 does not need to receive new module public key 111 in the form of a certificate 122 (although it could be in the form of a certificate 122). New module public key 111 could be received by server 105 (and sent by module 101) within a string or field within a body 602 of a TCP/UDP packet 601a, illustrated in FIG. 6b below. As depicted in step 516 shown in FIG. 6b below, message 208 at step 516 can also optionally include a module public key identity 111a, which can be recorded in module database 105k along with module identity 110 and module public key 111a. 
According to an exemplary embodiment, a first source (IP:port) number received in a first message 208 at step 516 can be different than a second source IP:port number in a second message 208 at step 518 below, wherein a response 209 send in step 519 below can preferably be sent to the second source IP:port number received in the second message 208 at step 518 in order to traverse a firewall 104 (as depicted and described in connection with packet 209a in FIG. 2). In other words, the proper destination IP:port for a response 209 to a module 101 can change over time, such as the proper destination IP:port changing due to the use of sleep states by module 101 and/or function of a firewall 104. Consequently, according to an exemplary embodiment, a response 209 can utilize a destination IP:port number equal to the source IP:port number received in the last (i.e. most recent) message 208 from module 101 received by server 105.
At step 517, server 105 and module 101 can authenticate the message 208 received in step 516 using the shared secret key 510 described in step 513. Server 105 could record the shared secret key 510 before step 517 in a module database 105k. If step 517 occurs for the first time in a lifetime of module 101, then shared secret key 510 could comprise a pre-shared secret key 129a recorded by server 105 in a module database 105k. If step 517 occurs at subsequent time, then server 105 could have sent shared secret key 510 in a server encrypted data 504 and recorded shared secret key 510 in a module database 105k for later use (such as at step 517). Server 105 and module 101 can authenticate the message 208 according to message digest, or using the shared secret key 510 to process a symmetric key 127 within a symmetric ciphering algorithm 141b, where the successful encryption and decryption of data within message 208 using the shared secret key 510 on both ends could be confirmation that message 208 is authenticated, since both parties would only be able to mutually successfully encrypt and decrypt by sharing the same shared secret key 510. As contemplated herein, the term “authenticating a public key” may refer to “authenticating a message that includes the public key”, and both may refer to validating or verifying that a recorded module identity 110 stored in server 105 is associated with a receive module public key 111.
Other possibilities exist as well for server 105 and module 101 to use a shared secret key 510 in order to authenticate a message 208 that contains a new module public key 111 (where module 101 contains a new module private key 112). In one embodiment, message 208 in step 516 could include a secure hash signature using secure hash algorithms 141c, where both the module 101 and the server 105 input a string combing at least a portion of the shared secret key 510 and a portion of the new module public key 111 into the secure hash algorithms 141c in order to obtain the secure hash signature. Module 101 could send the secure hash signature to server 105 in a message 208. The authentication of a new module public key 111 in step 517 is also depicted and described in step 1202 of FIG. 12 of U.S. patent application Ser. No. 14/064,618, filed Oct. 28, 2013 in the name of John Nix herein incorporated in its entirety.
The steps for module 101 to take for authenticating a derived module public key 111 can include the authentication and/or verification of either (i) new module public key 111 or (ii) a message 208 that includes new module public key 111 according to steps that use alternatives to a shared secret key 510. Thus, according to some exemplary embodiments (also discussed with step 1202 in FIG. 12 of U.S. patent application Ser. No. 14/064,618, filed Oct. 28, 2013 in the name of John Nix, new module public key 111 can be authenticated and/or verified as being properly associated with a recorded module identity 110 in server 105 (i) without the use of a shared secret key 510, and/or (ii) with alternatives to using shared secret key 510.
After receiving authenticated new module public key 111 in steps 516 and 517, according to a preferred exemplary embodiment, server 105 can preferably only accept and process (A) either incoming (i) a symmetric keys 127 ciphered with a asymmetric ciphering algorithm 141a, and/or (ii) incoming server instructions 414, when (B) the next or a subsequent incoming message 208 from module 101 using module identity 110 also includes a valid module digital signature 405 verified by using the new module public key 111, received at step 516.
According to an exemplary embodiment, shared secret key 510 can be associated with a module public key identity 111a, and shared secret key 510 can be used to authenticate a particular value for a module public key identity 111a. In this embodiment, (i) a message 208 with module public key 111 and a first module public key identity 111a may be authenticated using a shared secret key 510, but (ii) a second message with a second module public key 111 and a second module public key identity 111a may not be authenticated using the same shared secret key 510. Thus, in accordance with an exemplary embodiment, shared secret key 510 can be used for both (i) a single time for authenticating a module public key 111, and (ii) authenticating a module public key 111 with a particular value for the module public key identity 111a. Note that module public key identity 111a can be particularly useful with key revocation, such that a key revocation could specify a particular module public key identity 111a (associated with a particular module public key 111) to be revoked, but other module public keys 111 for a module 101 and module identity 110 with different module public key identities 111a could remain valid and not revoked.
Although not depicted in FIG. 5b, server 105 could operate with a certificate authority 118 in order to utilize a new module public key 111, as described in this paragraph. In this case, server 105 could bypass the authentication at step 517, but certificate authority 118 may perform step 517 in order to sign the certificate 122, including possibly using shared secret key 510 to authenticate module 101 with module identity 110 sending module public key 111. At step 516, new module public key 111 could be received by server 105 in the form of a uniform resource locator (URL) or domain name for download of a certificate 122 corresponding to the new module public key 111. Using a certificate authority 118 in conjunction with step 516 is also depicted and described in connection with FIG. 5b of U.S. patent application Ser. No. 14/055,606, filed Oct. 16, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety.
After steps 516 and 517, server 105 can update a module database 105k using the module identity 110 to insert or update the new module public key 111, and parameters 126 associated with new module public key 111. Server 105 may communicate with a plurality of modules 101, and thus could utilize a module database 105k in order to record the new module public key 111 and parameters 126 with the module identity 110. In one embodiment, the module identity 110 could preferably operate as an index within a table of module database 105k in order to speed reads and writes from the table used with module public key 111, parameters 126, and also selecting a symmetric key 127 for a symmetric ciphering algorithm 141b in later messages. As described in FIG. 1e, parameters 126 can include data useful for the operation of cryptographic algorithms 141 and module public key 111. According to a preferred exemplary embodiment, some modules 101 in a system 100, system 200, and other systems herein could utilize a first elliptic curve, such as, but not limited to, using a first set of ECC parameters 137 or first ECC standard curve 138 within a parameters 126, and other modules 101 could utilize a second and different elliptic curve within a parameters 126, such as, but not limited to, a second set of ECC parameters 137 or second ECC standard curve 138. The different parameters 126 for different modules 101 can be recorded by a server 105 in a module database 105 along with the module public key 111 from a step 516 and 517.
After verifying the new module public key 111 in a step 517, at step 518 of FIG. 5b, module 101 could send a second message 208, and the second message 208 can include a module identity 110 and module encrypted data 403. Although not depicted in FIG. 5b, the second message 208 could also include a module digital signature 405, wherein the module digital signature is created with the new module public key 111 sent by module 101 in step 516. Server 105 could then utilize the steps illustrated in FIG. 4 in order to process the incoming message 208 with the new module public key 111, including using the module identity 110 received in the second message 208 at step 518 to select the new module public key 111 and subsequently verify a module digital signature 405 using the new module public key 111 and digital signature algorithm 141d. Also as discussed in FIG. 4 in connection with processing a sent message 208, module 101 could encrypt the module encrypted data 403 in the second message 208 by using server public key 114. In one embodiment, the second message 208 as illustrated in FIG. 5b at a step 518, which could be the next message after authenticating module public key 111 in step 517, could include a symmetric key 127 and a module digital signature 405.
The module encrypted data 403 in step 518 could include a symmetric key 127 for utilization with a symmetric cipher 141b, where symmetric key 127 could be ciphered with an asymmetric ciphering algorithm 141a. In another embodiment, module 101 could also send sensor data in a module encrypted data 403 at step 518. Or, at step 518 the second message 208 could be a signal and/or data (such as a random number 128a) for server 105 to use a key derivation function 141f with the server public key 114 and the new module public key 111 (received at step 516) to create a new derived shared key 129b for use with symmetric ciphering algorithms 141b in subsequent messages 208. In other words, in some embodiments derived shared key 129b can function as a symmetric key 127. If the second message 208 in step 518 comprises a signal and/or data for server 105 to derive a new derived shared key 129b, then this second message 208 could then optionally leave off module encrypted data 403 and/or a module digital signature 405. The successful use of a new derived shared key 129b (using the new module public key 111, possible received in step 516, and existing server public key 114) with symmetric ciphering algorithms 141b at subsequent steps by both module 101 and server 105 can indicate to each the communications are mutually authenticated. Second message 208 could also include a server instruction 414, a security token 401, and/or a timestamp value 604a, and other possibilities exist as well without departing from the scope of the present invention.
At step 519, module 101 can receive a response 209 from server 105, where the response 209 includes server encrypted data 504 and a module instruction 502. Server 105 could take the steps to create and send response 209 as depicted and described in connection with FIG. 5a. Response 209 could be formatted according to the exemplary response 209 illustrated in FIG. 6a below. The module instruction 502 could be an acknowledgement 501 that the second message 208 sent in step 518 was received by server 105. At step 520, module 101 can send a third message 208 with a confirmation 414 to server 105. Confirmation 414 can be used to signal proper execution of module instruction 502 from a step 519, if module instruction 502 comprised an instruction other than an “ACK” or acknowledgement 501. In an embodiment where module instruction 502 in step 519 comprises an acknowledgement 501 from server 105, then the confirmation 414 may omitted and in this case step 520 could be skipped.
At step 521 module 101 or server 105 can determine or evaluate if a new module public key 111 and/or certificate 122 are required for continued operation. One reason for the need of new keys could be the expiration of a certificate 122 for module 101, or the desire to utilize a different set of cryptographic parameters 126 such as, but not limited to, a longer key length for increase security or the use of a different ECC parameters 137 or a different ECC standard curve 138 with cryptographic algorithms 141. As described elsewhere herein, many other possibilities exist for reasons why module 101 and/or server 105 can prefer for module 101 to utilize a new module public key 111 and new module private key 112. Either server 105 or module 101 may determine that the use of a new module public key 111 and new module private key 112 may be preferred at step 521. If module 101 determines that the use of a new module public key 111 and new module private key 112 is preferred or desirable, module 101 could send server 105 a signal that new keys will be generated either before step 521 or at step 521.
Upon determining new keys are desirable at step 521, then (i) server 105 could instruct module 101 to derive new private and public keys by returning to step 515, or (ii) module 101 could decide to return to a step 521. Although not depicted in FIG. 5b, upon determining “yes” at step 521, module 101 could receive (i) a module instruction 502 of “new key generation” from a server 105, and also (ii) a new or current set of cryptographic parameters 126 to utilize with the new module private key 112 and module public key 111 (where the new keys can be the next set of keys derived in a step 515). In accordance with exemplary embodiments, module instruction 502, including the “new key generation” instruction and set of parameters 126, can be received in a response 209 both (i) after module 101 wakes from a sleep or dormant state and sends a message 208 after waking from the sleep or dormant state, and (ii) before the expiration of a firewall port binding timeout value 117 after sending the message 208. If server 105 or module 101 determines that new keys are not required or desirable at step 521, server 105 and module 101 can then proceed to step 312 and wait for additional messages 208 from module 101 with module identity 110. Step 312 is also depicted and described in connection with FIG. 3. Other possibilities exist as well for a server to receive and respond to messages without departing from the scope of the present invention.
FIG. 5c 
FIG. 5c is a simplified message flow diagram illustrating exemplary steps for a wireless module to detach from a wireless network, in accordance with exemplary embodiments. As illustrated in FIG. 5c, a wireless module can utilize steps from FIG. 3. The wireless module 101 can wake from a sleep state 303, record sensor data 305, connect to a wireless network 102 using a connect procedure 522, send a message 208 to a server 105, and receive a response 209 from the server. As shown in FIG. 5a, wireless module 101 can optionally validate the response 209 from server 105 using the steps 505, which are also depicted and described in FIG. 5a. As contemplated herein, successfully completing a step 505 from FIG. 5a (such as successfully decrypting data using a key) can comprise validating the response 209, as depicted in FIG. 5c. Also, validating a response in FIG. 5c could comprise successfully verifying a server digital signature 506 in a step 501a from FIG. 5a. Note that validating response 209 may be included within the steps to receive response 209. According to one exemplary embodiment, after receiving the response 209, the wireless module 101 can then send a detach message 523 to wireless network 102.
The detach message 523 may be sent after receiving response 209 and before wireless module 101 sends or receives any other layer 3 messages to wireless network 102 or server 105. After receiving response 209, detach message 523 can be sent by wireless module 101 before (i) receiving a radio bearer reconfiguration message, and (ii) receiving a radio resource control connection release message. Exemplary radio bearer reconfiguration messages and radio resource control messages are depicted and described in connection with FIG. 3 of U.S. patent application Ser. No. 14/023,181, filed Sep. 10, 2013 in the name of John Nix, which is herein incorporated by reference. Detach message 523 can also be sent by wireless module 101 before the wireless module sends sending a radio resource control state change message. Note that a radio bearer reconfiguration message as described herein and throughout the present invention can also include both (i) a radio bearer release message, since release of radio bearer resources can comprise a reconfiguration of radio bearer resources (i.e. the configuration is the unallocation of radio resources), and (ii) a radio bearer configuration message, since configuration of radio resources can comprise a reconfiguration of radio resources (since a configuration of radio resources has taken place after message 208 was sent and the receipt of a subsequent radio bearer configuration message may thus be considered a “radio bearer reconfiguration message” as described throughout the present invention).
Also as described throughout the present invention, a “radio bearer reconfiguration” message can refer to a physical channel reconfiguration message. Thus, “radio bearer reconfiguration” as used in the above paragraph and elsewhere herein can refer to the “PHYSICAL CHANNEL RECONFIGURATION” message as specified in the 3GPP standard TS 25.303 (herein incorporated by reference), paragraph 6.2.3.3 and FIG. 15 of TS 25.303. Paragraph 6.2.3.3 specifies the messages for transition from Cell_DCH state to Cell_FACH state illustrated in FIG. 4a of U.S. patent application Ser. No. 14/023,181, filed Sep. 10, 2013 in the name of John Nix, herein incorporated by reference. In general the terms “radio bearer” and “physical channel” may be considered synonymous. Consequently, if wireless module 101 is attached to a 3G wireless network 102, detach message 523 may be sent before wireless module 101 receives a command from wireless network 102 to change from the Cell_DCH to another state such as Cell_FACH or the idle state (or possibly Cell_PCH or URA_PCH). Note that after the expiration of a timer, such as an exemplary 3-6 seconds, wireless network 102 sends wireless module 101 a radio bearer reconfiguration message if wireless module 101 takes no action and simply remains in the Cell_DCH state after receiving response 209 and awaits instruction from wireless network 102.
Detach message 523 can be sent after receiving response 209 and before receiving a radio resource control connection release message. When operating in a 4G LTE network, if wireless module 101 takes no action and simply remains in the RRC_Connected state after receiving response 209 and awaits instruction from wireless network 102, then a 4G LTE wireless network 102 would normally send the radio resource control connection release message after expiration of a timer, such as an exemplary 10 seconds illustrated in FIG. 4c of U.S. patent application Ser. No. 14/023,181, filed Sep. 10, 2013 in the name of John Nix. Note that 4G LTE Advanced may also comprise a 4G LTE wireless network as contemplated in the present invention, and 4G LTE may further comprise a 4G wireless network. Detach message 523 as contemplated in the present invention, when wireless module 101 connects to a 4G LTE wireless network, may comprise include a “detach request” message sent to wireless network 102 and may also comprise a detach procedure as specified in section 5.5.2.1 and 5.5.2.2 of ETSI/3GPP TS 24.301 (version 11.7.0, and herein incorporated by reference) and related standards. Detach message 523 may also comprise a similar message in 3G and also future wireless standards to indicate a complete disconnect of wireless module 101 from wireless network 102.
Although the radio resource control and radio bearer messages described above and throughout the present invention may pertain to specific messages within 3G and/or 4G LTE wireless wide area networking technologies, the detach message 523 can be sent (i) before wireless module 101 sends or receives radio control messages 524 with wireless network 102 that control radio resources for any appropriate wireless networking technology, (ii) after the response from the server has been received by the mobile device, and (iii) while the wireless device is actively connected to the wireless network. “Actively connected” in the previous sentence can mean the wireless module 101 can both send and receive data across the IP Network 107 in the actively connected state, and examples of the actively connected state include the RRC_Connected state (4G LTE) or Cell_DCH state (3G). Further, the radio control messages 524 may comprise layer 3 messages within a wireless network 102 for the allocation and control of radio resources between a wireless module 101 and wireless network 102, but excluding open loop and closed loop power control messages. In addition, if wireless network 102 utilized 2.5G or 2.75G (i.e. Enhanced Data Rates for GSM Evolution, or “EDGE”), the wireless module can send the detach message (i) while the wireless module comprises a general packet radio service (GPRS) ready state and (ii) before the wireless module utilizes a GPRS standby state, after receiving the response 209. Being actively connected to the wireless network may also comprise a state where the wireless module operates in a continuous receive mode and does not utilize a discontinuous receive (DRX) timer.
In addition to the timing for wireless module 101 to send detach message 523 listed in the previous paragraph, wireless module 101 could also send the detach message 523 after receiving response 209 and before either (i) sending a signaling connection release message or (ii) sending a radio resource control state change message (illustrated as element 307 in U.S. patent application Ser. No. 14/023,181, filed Sep. 10, 2013 in the name of John Nix). Thus, according to an exemplary preferred embodiment, wireless module 101 can send detach message 523 before sending a radio control message 524. If wireless network 102 comprises a 3G wireless network, the wireless module can send the detach message 523 (i) while the wireless module comprises a 3G dedicated channel (3G DCH) state, and (ii) before the wireless module utilizes a 3G forward access channel (3G FACH) state, with these states illustrated in FIG. 4a of U.S. patent application Ser. No. 14/023,181, filed Sep. 10, 2013 in the name of John Nix. If wireless network 102 comprises a 4G LTE wireless network, the wireless module can send the detach message 523 (i) while the wireless module comprises a radio resource control connected (RRC_CONNECTED) state and (ii) before the wireless module utilizes either a short or long discontinuous reception (DRX) state.
By sending the detach message soon after receiving response 209, preferably in an exemplary short time such as less than 1 second after response 209 has been received, the duration that a wireless module 101 remains in the Cell_DCH state (3G network) or RRC_Connected state (4G LTE network) can be minimized. As contemplated in the present invention, a 4G network can also comprise a 4G LTE network. By utilizing the efficient power management techniques described in the present invention, battery life can be conserved by reducing or minimizing the time the wireless module remains in the Cell_DCH or RRC_Connected states, or the equivalent active state, or connected state without use of a discontinuous receive, in future wireless network standards. Since the wireless module may have transmitted sensor data in a message 208, the wireless module 101 may have no more sensor data to transmit, and, thus, remaining in a state connected to the wireless network 102 would inefficiently utilize battery 101k resources.
After sending the detach message 523, the wireless module 101 can receive a radio resource control message 524, and the radio resource control message 524 can comprise a connection release message. Although not depicted in FIG. 5c, the radio resource control message 524 may comprise a series of messages between wireless module 101 and wireless network 102. This series of messages can be different for a 3G wireless network 102 and a 4G LTE wireless network 102, but the exact steps to complete the release of radio resources are known in the art.
After receiving a radio resource control message 523, the wireless module 101 can enter the sleep state 308. As described above, a sleep state for wireless module 101 may comprise (i) a sleep state for a radio 101z, a CPU 101b, or subsystems within a radio 101z, (ii) a dormant state for a radio 101z, CPU 101b, or subsystems within a radio 101z, or (iii) an idle state for radio 101z, CPU 101b, or subsystems within a radio 101z. Sleep state 308 can comprise power supply being effectively removed or disconnected from a radio 101z. After entering the sleep state 308, the wireless module can then periodically check a sleep timer at step 526, and wake from sleep if the timer has expired and report subsequent data from a sensor 101f to a server 105.
FIG. 6
FIG. 6 is a simplified message flow diagram illustrating an exemplary message sent by a module, and an exemplary response received by the module, in accordance with exemplary embodiments. FIG. 6 illustrates exemplary details within message 208 sent by module 101 and also response 209 received by module 101. Message 208 may comprise a TCP/UDP packet 601a sent from module 101 source IP:port 204 to server 105 destination IP:port 207. According to an exemplary embodiment, UDP or UDP Lite formatting for TCP/UDP packet 601a may be preferred. Source IP:port 204 and destination IP:port 207 in message 208 may be included within a header in TCP/UDP packet 601a. Although a single message 208, response 209, module 101, and server 105 are shown in FIG. 6, system 100 as illustrated in FIG. 1a and other systems depicted herein may comprise a plurality of each of the nodes and datagrams illustrated in FIG. 6. As contemplated herein, the term “datagram” may also refer to a “packet”, such that referring to as datagram 601a can be equivalent to referring to packet 601a. Note that when using TCP protocol, a packet within a series of TCP messages can also be a datagram 601a. 
TCP/UDP packet 601a may include a body 602, which can represent the data payload of TCP/UDP packet 601a. The data payload of message 208 can optionally include channel coding 406 as described in FIG. 4 above, if the transport protocol for TCP/UDP packet 601a supports the transmission of bit errors in the body 602 (as opposed to entirely dropping the packet), such as, but not limited to, with the UDP Lite protocol. Support for the transmission of bit errors in body 602 by wireless network 102 would be preferred over entirely discarding a packet, since the programs or algorithms used by a module controller 105x could include support for and utilization of channel coding 406. Without UDP Lite formatting, message 208 can alternatively sent by module 101 as a UDP datagram, such as if wireless network 102 (or a wired connection) does not support the UDP Lite protocol.
Note that if (A) message 208 comprises (i) regular UDP or TCP formatting (i.e. not UDP Lite or similar variations) within an IPv6 network, or (ii) a UDP or TCP format within an IPv4 network with a checksum 603 enabled (i.e. checksum 603 not equal to zero), then (B) channel coding 406 may optionally be omitted. Checksum 603 can comprise a value to for an integrity check of a packet 601a, and the calculation and use of checksum 603 is defined in IETF standards for TCP and UDP packets. In accordance with an exemplary embodiment, including the use of IPv6 for IP Network 107 and a UDP datagram for message 208 and response 209, a checksum 603 sent by module 101 in a message 208 does not equal a checksum 603 in the message 208 received by server 105, in the case where firewall 104 is present and the firewall 104 performs network address translation.
The body 602 can include a module identity 110, module encrypted data 403, and channel coding 406. The module identity 110 in FIG. 6 is illustrated as an encrypted module identity 110a, and the encrypted module identity 110a could be processed using a ciphering algorithm within a set of cryptographic algorithms 141 to convert the module identity 110 into an encrypted module identity 110a. Although not depicted in FIG. 6, body 602 could also include a module digital signature 405, as illustrated in FIG. 6 of U.S. patent application Ser. No. 14/039,401. Module identity 110 in the form of an encrypted module identity 110a is illustrated in FIG. 6 as external to module encrypted data 403, although module identity 110 may optionally only be included in module encrypted data 403, and in this case module identity 110 would not be external to module encrypted data 403 in a body 602. By including module identity 110 as external to module encrypted data 403, server 105 can use either (i) the unencrypted module identity 110 or (ii) decrypted encrypted module identity 110a in order to select either (i) the appropriate module public key 111 to verify module digital signature 405 if an asymmetric cipher 141a is used within cryptographic algorithms 141, or (ii) the appropriate symmetric key 127 for a set of cryptographic algorithms 141 to decrypt the module encrypted data 403. Module public key 111 and symmetric key 127 may preferably be recorded in a module database 105k, such that server 105 can access a plurality of public keys 111 or symmetric keys 127 associated with different module identities 110 with different bodies 602 for a plurality of modules 101.
Thus, by including module identity 110 (possibly in the form of an encrypted module identity 110a) external to module encrypted data 403, server 105 can utilize the module identity 110 to query a module database 105k and select the appropriate module public key 111 or symmetric key 127. As noted previously, module identity 110 could comprise a string or number that is uniquely associated with module identity 110, such as, but not limited to, a session identity, as opposed to being a module identity 110 that is read from hardware in module 101 such as, but not limited to, an IMEI number, Ethernet MAC address, etc. Module identity 110 is illustrated in FIG. 6 as a session identity that is a different representation of module identity 110 of a serial number such as in FIG. 2, but in both cases the values can comprise a module identity 110 since the values can be uniquely associated with module 101 at different points in time.
According to an exemplary embodiment where asymmetric ciphering 141a of module encrypted data 403 is utilized, such as (i) the first message 208 sent by module 101 and (ii) where a symmetric key 127 had not been previously exchanged, module identity 110 can be (a) within module encrypted data and (b) not external to module encrypted data 403. In this case, server 105 can utilize server private key 105c to, in sequence, decrypt module encrypted data 403, extract module identity 110 from the decrypted module encrypted data 403, and then use the module identity 110 to select module public key 111 from module database 105k in order to (i) verify a module digital signature 405, (ii) use a key derivation function 141f to derive a symmetric key 127, or (iii) send a response 209 with server encrypted data 504 processed with an asymmetric ciphering algorithm 141a and the selected module public key 111. In a related embodiment, if a module identity 110 is in body 602 and external to module encrypted data 403, then module identity 110 could be obfuscated or otherwise ciphered according to a pre-agreed algorithm with server 105, such that server 105 can utilize the obfuscated or ciphered module identity 110 to select a module public key 111 from module database 105k. The value of “[Encrypted Module Identity]” shown in FIG. 6 could comprise an encrypted module identity 110a, and the algorithm token 190 could be used with a cryptographic algorithm 141 illustrated in FIG. 1d (i) for a module 101 to convert a module identity 110 to an encrypted module identity 110a and also (ii) for a server 105 to convert an encrypted module identity 110a to a module identity 110. The use of an algorithm token 190 in a message 208 illustrated in FIG. 6 can be optionally omitted in exemplary embodiments. According to an exemplary embodiment where (i) symmetric ciphering 141b of module encrypted data 403 is utilized, such as after a first message 208 had already been sent by module 101 and a symmetric key 127 had previously been exchanged, then (ii) module identity 110 or encrypted module identity 110a can be external to module encrypted data 403 and in body 602 in order for server 105 to utilize module identity 110 and select symmetric key 127 from a module database 105k, thereby enabling server 105 to decrypt the module encrypted data 403 using the selected symmetric key 127 and a symmetric ciphering algorithm 141b. 
In exemplary embodiments, a module digital signature 405 may optionally be omitted from body 602 after module 101 has previously sent symmetric key 127 in a previous message 208 to the message 208 illustrated in FIG. 6. In other words, in a series of messages 208, module 101 can preferably change from (i) using asymmetric ciphering 141a with in a previous message 208 that includes symmetric key 127 in a module encrypted data 403 (where the initial message 208 also includes module digital signature 405 and module identity 110) to (ii) using symmetric ciphering 141b with subsequent messages 208 without module digital signature 405 in the series (where the subsequent messages 208 can optionally include an encrypted module identity 110a external to module encrypted data 403 for server 105 to select the appropriate symmetric key 127). Message 208 illustrated in FIG. 6 can comprise a subsequent message 208 as described in the previous sentence. A series of messages 208 could begin when the initial message 208 is sent by module 101 and end when expiration time 133 of symmetric key 127 has transpired, and subsequently a new series of messages 208 could begin where the first message 208 in the new series of messages changes back to asymmetric ciphering 141a with initial message 208 that includes symmetric key 127 in a module encrypted data 403 (where the initial message 208 also includes a new module digital signature 405). An example of the initial message 208 with a symmetric key 127 described in this paragraph can comprise message 208 illustrated in FIG. 6 of U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety. Other possibilities exist as well without departing from the scope of the present invention.
Using a message 208 with a module digital signature 405 can be both more efficient and overall more secure than digest authentication (such as the digest authentication described in IETF RFC 2069), although using digest-based authentication may be alternatively used. The use of a module digital signature 405 requires only a single packet for message 208 and a single packet for response 209 for secure communication between module 101 and server 105. Module encrypted data 403 illustrated in FIG. 6 can be processed using the steps and algorithms described in FIG. 4. Note that module encrypted data 403 as illustrated in FIG. 6 is shown in a plaintext form for ease of illustration, but actual module encrypted data 403 within body 602 of a packet 601a could be transmitted as binary, hexadecimal, Base64 binary-to-text encoding, or other encoding rules, and strings of the actual data within module encrypted data 403 sent across an IP network 107 would not normally be human readable.
In an exemplary embodiment, encryption by module 101 may optionally be omitted, and the server instruction 414 with corresponding data could be included within a message 208 without encryption within the body 602, such as if security could be maintained at the network level. As one example for this embodiment without encryption, server instruction 414 could be included in body 602 as plaintext. The encryption and/or security could be applied through other means, such as, but not limited to, the use of symmetric ciphering 141b such as AES 155 at the data-link layer, where packets transmitted through a wireless network 102 could be encrypted at the data-link layer, but after conversion to a network-layer message such as the exemplary datagram 601a illustrated in FIG. 6, the datagram 601a could optionally omit encryption such as a module encrypted data 403. Or, encryption of message 208 could be applied at both the data-link layer and within the datagram 601a by including a module encrypted data 403.
Module encrypted data 403 can include a server instruction 414, a server identity 206, a module identity 110, a security token 401, a timestamp 604, and a sensor measurement 305. The server instruction 414 can represent the purpose of the message 208 for server 105, and FIG. 6 illustrates an “update” for server instruction 414. An update for server instruction 414 could be used to periodically notify server 105 of regular, periodic sensor measurements 305 acquired by a sensor 101f or also data from a plurality of sensors. An update for server instruction 414 may also comprise a periodic report regarding monitored unit 119, and a server instruction 414 is described in FIG. 4. Other server instructions 414 besides an “update” may be included in a module encrypted data 403 within a body 602. The “update” illustrated in message 208 in FIG. 6 can also include a new symmetric key 127, and the module encrypted data 403 illustrated in FIG. 6 may comprise the use of either an asymmetric ciphering 141a with public/private keys, or (ii) symmetric ciphering 141b with a symmetric key 127.
An initial transmission or negotiation of a symmetric key 127 may preferably utilize asymmetric ciphering 141a and the use of a public key as an encryption key and a private key as a decryption key. Subsequent transmission of a new symmetric key 127 may utilize either (i) a symmetric cipher 141b with a previously negotiated but still valid symmetric key 127 (i.e. expiration time 133 has not transpired), or (ii) asymmetric ciphering 141a. If the data within instruction 414 is longer than the maximum data length supported by a selected asymmetric ciphering algorithm 141a and the public/private key pair, then module encrypted data 403 within message 208 can be broken up into several sections, such that the data within each section is less than the maximum data length supported by the asymmetric ciphering algorithm 141a and key length. In an exemplary embodiment, a first symmetric key 127 can be used with module encrypted data 403 and a second symmetric key 127 can be used with server encrypted data 504. The first symmetric key 127 and second symmetric key 127 can be different, including using a first symmetric ciphering algorithm 141b with the first symmetric key and a second symmetric ciphering algorithm 141b with the second symmetric key 127. In another exemplary embodiment, in order to reduce the number of messages required to be transmitted and thus save power usage by a module 101, symmetric key 127 used with module encrypted data 403 and server encrypted data 504 can be the same and rotated periodically such, but not limited to, when expiration time 133 for a symmetric key 127 transpires.
Module identity 110 within module encrypted data 403 can represent the identity of module 110, and could represent a serial number read by module 101 from a read-only hardware address. Module identity 110 is described in FIG. 1c and can represent a unique identifier of module 101. Module identity 110, such as an encrypted module identity 110a, outside module encrypted data 403 can represent a string or number that is different than a serial number that can be used by module 101 within a module encrypted data 403. Security token 401 within module encrypted data 403 can represent a random string in order to make message 208 reasonably unique and thus system 200 in FIG. 2 and other systems illustrated herein robust against replay attacks. Security token 401 is described in FIG. 5a. Timestamp 604 can represent a time value that module 101 sends message 208 or a time value that module 101 acquired sensor data 305. Sensor data 305 is described with the description of a sensor 101f in FIG. 1c, and sensor data 305 can represent data module 101 acquires using sensor 101f. Sensor data 305 within message 208 may be stored by server 105 in a module database 105k, or potentially forwarded to another server such as, but not limited to, a module provider 109 for additional processing. Sensor data 305 can comprise a wide range of values for a sensor 101f besides the exemplary value of a temperature reading shown in FIG. 6, including raw sensor data, compressed sensor data, and processed or averaged data. The specific sensor data 305 shown in FIG. 6 is illustrated to be exemplary and not limiting for sending and receiving sensor data. Sensor data 305 may also be referred to as a sensor measurement 305.
FIG. 6 also illustrates exemplary details within response 209 sent by server 105. Response 209 may comprise a TCP/UDP packet 601b sent from server 105 IP:port 207 the IP address 210 and port number 605, where IP address 210 represents the external IP address of wireless network firewall 104, if present, and port number 605 is the source port in message 208 as received by server 105 (i.e. the source port in message 208 after traversing the firewall 104 illustrated in FIG. 6a). Thus, IP:port with IP address 210 and port number 605 in response 209 may be different than IP:port 204 in message 208, since the presence of a wireless network firewall 104 may perform NAT routing, which could change the source IP address and source port number from IP:port 204 to IP address 210 and port number 605 in message 208, as received by server 105. The use of wireless network firewall 104 in wireless network 102 may require that response 209 be sent from IP:port 207 to IP address 210 and port number 605 in order to be properly processed by firewall 104 and forwarded to module 101 at IP:port 204. Source IP:port 207 and destination IP address 210 and port number 605 in response 209 may be included within a header in TCP/UDP packet 601b, as illustrated in FIG. 6. TCP/UDP packet 601b could comprise a regular UDP packet, a UDP Lite packet, or a TCP datagram, or similar protocols supported by an IP Network 107. TCP/UDP packets 601a and 601b may utilize the same protocol.
As noted previously, the use of checksums may be mandatory in IPv6 networks, and thus a response 209 comprising a packet 601b can include a checksum value 603 (illustrated in message 208 but not response 209) for the header. The use of firewalls such as firewall 104 can change the header values in a packet 601b. In accordance with a preferred exemplary embodiment, a first checksum value 603 within a response 209 sent by server 105 can be different and/or not equal to a second checksum value 603 within the response 209 received by module 101. Likewise, in an exemplary embodiment, a first checksum value 603 within a message 208 sent by a module 101 can be different and/or not equal to a second checksum value 603 within the message 208 received by server 105, potentially due to the presence of a firewall 104 or other router that performs network address translation, where the destination IP address within a response 209 sent by a server 105 is different than the IP address 204 of a module 101.
A UDP, TCP, or UDP Lite datagram as a TCP/UDP packet 601b within response 209 may include a body 606. Body 606 may comprise the payload or data within a UDP, TCP, or UDP Lite packet. Body 606 can include a server identity 206, a server digital signature 506 (not shown in FIG. 6), server encrypted data 504, and channel coding 406. Server identity 206 is illustrated in FIG. 6 as external to server encrypted data 504 within body 606, but server identity 206 may optionally be included in server encrypted data 504 instead. Module 101 may communicate with a plurality of servers 105, and server identity 206 as external to server encrypted data 504 can allow module 101 to select the appropriate symmetric key 127 to utilize for decrypting server encrypted data 504 (since each of the multiple servers 105 that module 101 communicates with may utilize a different symmetric key 127).
Also note that the server identity 206 can be similar to module identity 110, such that multiple different values for server identity 206 could be utilized in different systems illustrated herein, but each of the different values could preferably be uniquely associated with a server 105. As one example, server identity 206, outside server encrypted data 504 as illustrated in FIG. 6, may comprise a session identity or session identifier, as opposed to a different server identity 206 that could comprise a hardware serial number or domain name for server 105. Thus, server identity 206 outside a server encrypted data 504 may be a different string or representation than server identity 206 within server encrypted data 504, but both strings/numbers used for server identity 206 in response 209 could be associated with server 105. In an exemplary embodiment, a set of servers 1010 (illustrated in FIG. 10) can collectively use a server identity 206 and function as a server 105 depicted in FIG. 6.
Although not depicted in FIG. 6, a server digital signature 506 in body 606 can comprise a secure hash signature of a subset of body 606, where the subset of body 606 can comprise server encrypted data 504, and/or server identity 206 as illustrated in FIG. 6. The use of a server digital signature 506 in a body 606 is illustrated in FIG. 6 of U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety. In this manner, module 101 can utilize server digital signature 506 to authenticate that response 209 was sent by server 105. Channel coding 406 in body 606 is also depicted and described in connection with FIG. 5a above. The server digital signature 506 may optionally be omitted as well.
Body 606 may include server encrypted data 504. Server encrypted data 504 is depicted and described in connection with FIG. 5a above. Server encrypted data 504 may include an acknowledgement 501, wherein acknowledgement 501 can notify module 101 that message 208 has been received by server 105. As illustrated in FIG. 6, server encrypted data 504 may optionally also include a module instruction 502 for module 101. The module instruction 502 could be a string that contains instructions or configuration parameters for module 101, such as an order to change state, parameters regarding the monitoring of monitored unit 119, server names or addresses, radio frequency parameters, timer values, settings for actuator 101y, etc. A module instruction 502 is depicted and described in connection with FIG. 5a above. The exemplary module instruction 502 illustrated in FIG. 6 comprises a “derive new PKI key pair” 608 instruction for module 101 derive a new set of keys, also depicted and described in connection with FIG. 5b above at a step 521 then step 515.
In an embodiment where module 101 uses an eUICC 163, server encrypted data 504 could include a received eUICC profile 163a. In an exemplary embodiment, the server 105 sending the received eUICC profile 163a can be different than a server 105 receiving sensor data 305. In these embodiments where the server 105 sending the received eUICC profile 163a is different than the server 105 receiving sensor data 305, module 101 can send the server 105 (possibly associated with or operated by an eUICC subscription manager 164) a message 208 before receiving the response 209 with the server encrypted data 504 containing the received eUICC profile 163a. The message 208 to the server 105 operated by an eUICC subscription manager 164 could include a module digital signature 405 processed by a module 101 using a module private key 112. In this manner, the server 105 associated with the eUICC subscription manager 164 can verify the message 208 is sent by the correct and/or authenticated module 101 before sending the received eUICC profile 163a in a response 209. Note that a received eUICC profile 163a may be encrypted with a either (i) a symmetric ciphering algorithm 141b or an asymmetric ciphering algorithm 141a before encapsulation in a response 209, and in this case the server encrypted data 504 for receiving the received eUICC profile 163a may optionally be omitted. In other words, the received eUICC profile 163a may not need additional encryption by a server 105 for transmission since the received eUICC profile 163a may already be encrypted.
Other possibilities for a module instruction 502 within a response 209 are possible as well without departing from the scope of the present invention. Although not depicted in FIG. 6 or FIG. 2, if response 209 includes a module instruction 502, according to an exemplary embodiment, module 101 can preferably send a second message 208 to server 105, where the second message 208 includes a confirmation that module instruction 502 was successfully executed or implemented by module 101. This confirmation could be included in a server instruction 414 for server 105 within a second message 208, and the confirmation could include a timestamp value 604 for when the module instruction 502 was executed. A timestamp value 604 may be useful for tracking time of actions and data collected, when a module 101 may only periodically have access to a network 102 and also may periodically be dormant or sleep.
Also, although a server encrypted data 504 may be included within a body 606 in exemplary embodiments, body 606 may optionally omit server encrypted data 504 and include data from server 105 or a set of servers 1010 (illustrated in FIG. 10) that is not encrypted, such as, but not limited to, plaintext. As one example in this case, acknowledgement 501 could be included in body 606 as plaintext. Also, although not depicted in FIG. 6, server encrypted data 504 could include a symmetric key 127 for module 101 to utilize with symmetric ciphering 141b in cryptographic algorithms 141 for processing a module encrypted data 403 in subsequent messages 208 and/or responses 209. Server encrypted data 504 in a response 209 may include a security token 401. Security token 401 may be a random string and may also be generated by either server 105 or module 101. If security token 401 is generated by module 101, then security token 401 may be included in message 208 and also utilized by server 105 in response 209, as illustrated in FIG. 6. Other possibilities exist as well without departing from the scope of the present invention.
FIG. 7
FIG. 7 is a flow chart illustrating exemplary steps for a module to derive a series of public keys and private keys, including sending and authenticating the derived public keys, in accordance with exemplary embodiments. In order to utilize communications secured with PKI techniques such as private keys, public keys, certificates, and identities, a module 101 may preferably obtain or generate the keys and certificate in a secure manner. Given that a plurality of modules 101 may be deployed in potentially remote places, without frequent contact with end users or technicians, the use of secure PKI techniques for a module 101 can create a significant set of challenges for the generation of module public key 111 and module private key 112, as well as properly and securely obtaining a certificate 122 with an module identity 110. Using conventional technology, significant challenges and costs can be incurred when (i) module 101 has already been deployed, such as collecting data from a monitored unit 119, and (ii) module 101 needs to utilize either (a) a new set of module private key 112 and module public key 111 or (b) a new UICC card. In exemplary embodiments, a module 101 could implement steps within FIG. 7 in order to utilize an eUICC 163 in order to connect with a wireless network 102. The use of an eUICC 163 for connecting with a wireless network 102 is optional, and the steps illustrated in FIG. 7 can be conducted without the use of an eUICC 163.
The proper use of a new set of module private key 112 and module public key 111 may utilize the particular steps and procedures contemplated herein, in order to minimize any potential human intervention (with related costs) while continuing to maintain security. Over a long period of operating time for a module 101, such as a decade or longer, there may be many reasons module 101 may need a new pair of PKI keys, such as (i) expiration of a certificate, or the certificate of a parent signature authority, (ii) the transfer of ownership or control of module 101, where the prior ownership could have direct or indirect access to the module private key 112, (iii) supporting a new server 105 that has different security requirements or a different set of cryptographic parameters 126 (such as, but not limited to longer keys, different ECC curves, etc.), (iv) revocation of a public key in a chain of signatures 123 within a certificate 122, and/or (v) the use of a new activated eUICC profile 163b. In the case of (ii), new ownership of module 101 may require a module 101 to utilize a new module private key 112. In the case of (iii) a new server 105 may require a pair of public/private keys incompatible with a prior set of public/private keys utilized by module 101 and/or a certificate 122 for module 101. Other possibilities exist as well for reasons a module 101 may need to derive a new module public key 111 and new module private key 112.
The general approach adopted by most mobile phone networks over the past two decades has been founded upon the use of a pre-shared secret key recorded in SIM cards and UICCs, such as the Ki secret key in 2G/3G networks and shared secret key K in 4G LTE networks. That approach may work for mobile phones, where the SIMs can often be easily replaced, but the use of a pre-shared secret key in a SIM may not be suitable for a module 101 and M2M service provider 108. As one example, significant costs may be incurred by swapping out a SIM card for already deployed modules 101, especially if they are in remote locations or continually moving such as a tracking device on a container or pallet, or a truck or automobile. Next, a module 101 may preferably record multiple pairs of public/private keys 111/112 for various functions, such as connecting to different servers 105, connecting to different wireless networks 102, etc. The number of pairs of public/private keys useful to a module 101 concurrently could be many, such as an exemplary two or more actively used public/private keys. Trying to change or add a new SIM card each time a new security key is required may not be efficient or feasible. FIG. 7 illustrates exemplary steps that can be performed with module 101, including using a module program 101i, for generating and/or updating a module public key 111 and module private key 112. The steps illustrated in FIG. 7 include both (i) an “initial” or “startup” case where module 101 has not previously derived keys, and (ii) a subsequent or “follow on” time where module 101 can generate or derive keys after the initial derivation of keys. The steps illustrated for the derivation of new module PKI keys in FIG. 7 can also be used for an eUICC 163.
At step 701, during manufacturing of module 101, including manufacturing of sub-components such as a circuit board or assembly of hardware components illustrated in FIG. 1c, etc., a module identity 110 could be written into the hardware, and could comprise a serial number, International Mobile Equipment Identity (IMEI) number, Ethernet MAC address, etc. For security purposes, a module identity 110 may preferably be written into a read-only location, such as a readable location on a system bus 101d, which could also comprise a ROM 101c. The read-only location could also comprise a protected memory or protected address within module 101. A protected memory could also comprise a memory location within a ROM 101c. Recording and utilizing module identity 110 is also depicted and described in connection with FIG. 1c, FIG. 2, and elsewhere herein. Alternatively, module identity 101 could be recorded in a non-volatile memory such as a flash memory 101w. 
At step 702, module 101 can be distributed to end users and also installed with a monitored unit 119. At step 703, parameters 126, and a server address 207 can be recorded in a nonvolatile memory 101w. Parameters 126 may comprise settings or values for a cryptographic algorithms 141 as illustrated in FIG. 1 d and FIG. 1 e, including (i) key lengths, (ii) algorithms to utilize for key generation or ciphering, such as the specification of an elliptic curve utilized illustrated as parameters 126 in FIG. 1e, (iii) a specific secure hash algorithm 141c to utilize, such as SHA-256 or SHA-3, (iv) an expiration date of the public key 111, and/or (v) a maximum time value for an expiration time 133 associated with symmetric keys 127, etc. The parameters 126 in a step 703 could comprise either a first set of cryptographic parameters 126 or a first subset of cryptographic parameters 126a. Although not depicted in FIG. 7, at step 702 a configuration file could also be loaded into non-volatile memory, where the configuration file includes a plurality of fields specifying the operation of module 101. The parameters 126, and server address 207 could be included in a configuration file.
Continuing at step 703, server name 206 could be utilized in place of or in addition to server address 207, and in this case module 101 can later perform a DNS or DNSSEC lookup using server identity 206 in order to obtain server address 207 for use in a message 208. Server address 207 (or server identity 206) could also be recorded in a ROM 101c at step 703. Step 703 may also be performed concurrently with step 701 or step 702. Note that step 703 may take place multiple times during the lifetime of a module 101, and in this case (a) the first time step 703 is conducted, step 703 could be conducted concurrent with steps 701 or 702, and (b) a subsequent time step 703 is conducted, step 703 could be conducted after the receipt of a response 209, where the response 209 includes a second server address 207, and also potentially a new module identity 110. In other words, although not depicted in FIG. 7, a module 101 could return to step 703 from later steps upon the equivalent of a “factory reset”, or similar command where flash memory 101w and other nonvolatile memory would be cleared. One example could potentially be the transfer of ownership of module 101, or a second example could be the upload of new firmware that is incompatible with a previous configuration file.
Continuing at step 703, shared secret key 129 may comprise a shared secret key 129c or a pre-shared secret key 129a. Given that module 101 may not derive a private key until a step 515 illustrated below in FIG. 7, a derived shared secret key 129b may not be available from a key derivation function 141f at step 702. A shared secret key 129c could be a value depicted and described in connection with FIG. 1c. For embodiments where the module 101 utilizes an eUICC 163 to connect with a wireless network 102, the recording of shared secret key 129 and related data in a step 703 can comprise recording a received eUICC profile 163a. The shared secret key 129 can comprise a shared secret key 510 as depicted and described in connection with step 513 and related steps in FIG. 5b. In another embodiment, the shared secret key 129 in a step 703 could comprise a initial key K recorded in a received eUICC profile 163a, also depicted and described in connection with FIG. 1c. The first set of cryptographic parameters 126 and the server address 207 could also be recorded in the eUICC 163 in the form of a received eUICC profile 163a. 
In an exemplary embodiment, shared secret key 129 could be obtained and loaded by a distributor, installer, or end user into a nonvolatile memory such as flash memory 101w in the form of a pre-shared secret key 129a, where pre-shared secret key 129a was obtained using a module identity 110 and pre-shared secret key code 134 as depicted and described in connection with FIG. 1c above. Module 101 could also utilize a first pre-shared secret key 129a, including a first pre-shared secret key 129a entered by potentially a distributor, installer, or end-user discussed in FIG. 1c, to derive shared secret key 129. Other possibilities exist as well for shared secret key 129, and shared secret key 129 can be useful for either the authentication of module 101 and/or the proper identification of module 101 upon module 101's generation of a private key 112 and public key 111, as described below, including step 705. For embodiments where the module 101 utilizes an eUICC 163 to connect with a wireless network 102, an initial, received eUICC profile 163a could be loaded into a nonvolatile memory by a manufacturer, distributor, installer, or end-user, and the data for a step 703 could be recorded in the initial, received eUICC profile 163a. Or, the module 101 could include both a UICC and an eUICC 163, and the module 101 could use the physical UICC to initially connect with a first wireless network 102, and subsequently use a received eUICC profile 163a and the eUICC 163 to connect with a second, subsequent wireless network 102.
In an exemplary embodiment, an initial module private key 112b and initial module public key 111b could be recorded into nonvolatile memory at step 703. For example, a manufacturer, distributor, installer, technician, or end-user could load the initial module private key 112b and initial module public key 111b, where the initial module public key 111b would be utilized to authenticate at step 705 a subsequent set of public/private keys derived by module 101 at step 704. In this case, the initial module public key 111b and/or initial module private key 112b described in the previous two sentences could comprise the shared secret key 129. One reason the initial module private key 112b with the initial module public key 111b could comprise a shared secret key 129 can be, if the initial module public key 111b and initial module private key 112b are present, (i) the initial module private key 112b and initial module public key 111b together have been “shared” in the sense that the initial module private key 112b has been located outside module 101 and in possession of an entity such as the manufacturer, distributor, installer, technician, or end-user in order to load the initial module private key (and initial module public key 111b is shared with server 105), (ii) the initial module private key 112b and initial module public key 111b can be used to authenticate a subsequent message 208 containing a public key internally derived by the module at step 704 below, and (iii) the initial module private key 112b would remain “secret” and not publicly shared. Thus, FIG. 7 contemplates an embodiment where shared secret key 129 at step 703 comprises an initial public/private key pair that is not internally derived by module 101.
Note that the contemplation of the use of shared secret key 129 as a pre-shared secret key 129a within the present invention may be different than the use of a pre-shared secret key within a SIM card. Specifically, as depicted and described in connection with FIG. 1c and elsewhere herein, the shared secret key 129, comprising any of (i) a pre-shared secret key 129a, (ii) derived from a pre-shared secret key 129a, or (iii) a shared secret key 129c, may be moved by CPU 101b into a volatile memory such as RAM 101e, with subsequent access by cryptographic algorithms 141. In contrast, the pre-shared secret key within a SIM card or UICC for mobile phones is usually designed to prevent movement of the pre-shared secret key within a SIM or UICC into RAM 101e. 
At step 704, module 101 can authenticate with a server 105 using the data from a nonvolatile memory recorded in step 703. In the embodiment where a module 101 uses an eUICC 163 to connect with a wireless network 102, the server 105 could be operated by a M2M service provider 108 and also could be associated with or reside in wireless network 102. In an exemplary embodiment, a module 101 can be distributed or installed between steps 703 and steps 704. In order to perform 2-way authentication at a step 704, module 101 can read module identity 110 using a read-only address or a protected address. Module 101 can read module identity 110 directly from read-only hardware address by using system bus 101d, including from a ROM 101c, or module 101 can read module identity 110 from a nonvolatile memory such as a flash memory 101w. Thus, the read-only address or protected address could comprise an address accessible on system bus 101d that is designated read-only for a period of time.
As contemplated herein, a protected address can comprise an address or a memory location that can be read-only (i) for a period of time and/or (ii) upon an elevated set of privileges not normally used in the operation of a module 101. The module identity 110 used in a step 704 for authentication could be recorded into a flash memory 101w by module 110 after a prior read of module identity 110 from a read-only address or a protected address. In this case (module 101 taking the step described in the previous sentence), reading module identity 110 from the nonvolatile memory at step 704 can also comprise module 101 reading module identity 110 using a read-only address or a protected address. Thus, although module 101 may read module identity 110 from a flash memory 101w, if (a) module 101 initially utilized a read-only address to record the module identity 110 into the flash memory 101w, then (b) reading module identity 110 from the flash memory 101w would comprise using a read-only address to read module identity 110. Other possibilities exist as well, such as the address that includes module identity 110 in either (i) a nonvolatile memory such as a ROM 101c or (ii) an address accessible on system bus 101d, could be designated for a period of time as available for a read-only or protected operations.
Note that using a module identity 110 from a read-only address or a protected address within module 101 can be important for the use of an eUICC 163. The module identity 110, possibly in the form of a hardware serial number or IMEI, can serve as the basis for an identifier or identity of module 101 with an eUICC subscription manager 164, since a module identity associated with a wireless network such as an IMSI or GUTI can change for the same module 101 over time as different received eUICC profiles 163a can be activated. In other words, a module 101 can use the module identity 110 in order to receive a received eUICC profile 163a from an eUICC subscription manager 164 instead of, or in addition to, a network module identity from the eUICC subscription manager 164 since a network module identity can change for a module 101 over time when using an eUICC 163.
Continuing at step 704, module 101 can take steps to conduct a 2-way authentication with server 105. In order for module 101 to authenticate with server 105, module 101 can send a message 208 with a module identity 110 to the server address 207, which could belong to a server 105. In an exemplary embodiment, module identity 110 at a step 704, or any step where module 101 authenticates or verifies identity with a server 105, can comprise the form of an encrypted module identity 110a. In this case, the message 208 with an encrypted module identity 110a would also preferably include an algorithm token 190 used by module 101 to derive the encrypted module identity 110. The server could extract the plaintext module identity 110 using a cryptographic algorithm 141. Alternatively, the module identity 110 could be sent as plaintext in a step 704. In order to authenticate module 101 with module identity 110 at step 704, server 105 can utilize the shared secret key 129 to authenticate module 101 at step 704, such that after authentication, the contents of message 208 or additional messages 208 from module 101 can be further processed.
For embodiments where the module 101 utilizes an eUICC 163 to connect with a wireless network 102, the 2-way authentication using shared secret key 129 at a step 704 could comprise module 101 conducting a 2-way authentication with a server 105 associated with an eUICC subscription manager 164. The shared secret key 129 and related data in a step 704 could be read from a received eUICC profile 163a. The shared secret key 129 can comprise a shared secret key 510 within a received eUICC profile 163a. For embodiments where the module 101 utilizes an eUICC 163 to connect with a wireless network 102, the 2-way authentication could be conducted with an initial key K from the eUICC profile 163b in a step 704 using the standard 2-way authentication for an LTE and related networks where the wireless network 102 sends a RAND and AUTN, and module 101 sends a RES. In this case, the shared secret key 129 could comprise the initial key K.
Continuing at step 704, server 105 can authenticate module 101 using the module identity 110 in message 208 and a message digest, such as described in IETF RFC 2617, titled “HTTP Authentication: Basic and Digest Access Authentication”. Other reasonably secure authentications techniques using a shared secret key 129 could be utilized without departing from the scope of the present invention. In order to authenticate, module 101 could take steps to demonstrate to server 105 that module 101 holds the same shared secret key 129. Module 101 can properly respond to a challenge/nonce in a message digest authentication by sending a secure hash value calculated using (i) the challenge/nonce and (ii) the shared secret key 129. Or, module 101 could authenticate by generating a module digital signature 405 in message 208 using the shared secret key 129. In addition, module 101 could utilize the shared secret key 129 as a symmetric key 127 to encrypt a module encrypted data 403 with symmetric ciphering 141b, and if server 105 could properly decrypt the module encrypted data 403 using the same shared secret key 129 on the server, then server 105 would know the correct module 101 sent the message 208 and thereby would be authenticated. Other possibilities exist as well for a module 101 to authenticate with a server 105 using a shared secret key 129, a shared secret key 510, or an initial key K from an eUICC profile 163b in the case where module 101 uses an eUICC 163 to connect with a wireless network 102, without departing from the scope of the present invention.
Continuing at step 704, module 101 can also preferably authenticate server 105 in order to complete a 2-way authentication. Module 101 can take steps to ensure or verify that server 105 with reasonable assurance also holds the shared secret key 129, or a shared secret key 510 or an initial key K in the case where module 101 uses an eUICC 163 to connect with a wireless network 102. Module 101 could authenticate server 105 using message digest, such that module 101 uses a challenge/nonce or random number, and verifying that server 105 properly responds to the challenge/nonce with a correct secure hash value, such as the output from a secure hash algorithms 141c. Or, server 105 could authenticate with module 101 by the module receiving a server digital signature 506 in a response 209 using the shared secret key 129. In addition, module 101 could utilize the shared secret key 129 as a symmetric key 127 to decrypt a received server encrypted data 504 with symmetric ciphering 141b, and if module 101 could properly decrypt the server encrypted data 504 using the shared secret key 129, then module 101 would know the correct server 105 sent the response 208 and thereby the server 105 would be authenticated. Other possibilities exist as well for a server 105 to authenticate with a module 101 using a shared secret key 129 without departing from the scope of the present invention.
Continuing at step 704, module 101 can receive a set of cryptographic parameters 126, preferably after module 101 completes authentication with server 105 (in order for server 105 to not send the set of cryptographic parameters 126 to 3rd parties). A set of cryptographic parameters 126 received in a step 704 can also comprise a second set of cryptographic parameters 126, where the second set of cryptographic parameters 126 could be different or the same as the first set of cryptographic parameters 126 from a step 703. The second set of cryptographic parameters 126 at a step 704 can comprise a subset of cryptographic parameters 126a as depicted and described in connection with FIG. 1e. Module 101 could send the set of cryptographic parameters 126 recorded in step 703 to the server 105, and the server 105 could respond with a subset of cryptographic parameters 126a. In another embodiment, server 105 could send module 101 the second set of cryptographic parameters 126 at step 704, and module 101 could send a subset of the cryptographic parameters 126a to the server. In embodiments where module 101 uses an eUICC 163, receiving the second set of cryptographic parameters 126 at a step 704 could comprise receiving a received eUICC profile 163a that includes the second set of cryptographic parameters 126.
At the conclusion of step 704 the module 101 and server 105 can preferably agree on a set of cryptographic parameters 126 for use with cryptographic algorithms 141 for further communication. Note that a module 101 and a server 105 can communicate a set of cryptographic parameters 126 by using a set of cryptographic parameters token 126c, such that a packet transmitted could contain the token 126c as an identifier for a set of cryptographic parameters 126. For example, a module 101 could send or receive the token 126c with an exemplary value of “Set A” illustrated in FIG. 1e, instead of sending or receiving the complete set of cryptographic parameters 126. In an exemplary embodiment, the transmission of cryptographic parameters 126 or a token 126c at a step 704 comprises encrypting the cryptographic parameters with shared secret key 129 as a symmetric ciphering key 127 in a symmetric ciphering algorithm 141b. Note that receiving a second set of cryptographic parameters 126 could optionally be omitted from a step 704, and in this case the first set of cryptographic parameters 126 or subset of cryptographic parameters 126a from a step 703 could be used by a module 101 in a subsequent step 515 below in FIG. 7. In embodiments where module 101 uses an eUICC 163, the second set of cryptographic parameters in a step 704 could comprise the set of cryptographic parameters 126 within a received eUICC profile 163a, and a module 101 could receive the second set of cryptographic parameters 126 using a system bus 101d. In other words, when a module 101 is depicted in FIG. 7 and other Figures herein as receiving data, exemplary embodiments contemplate that a CPU 101b within module 101 receiving the data using a system bus 101d, and thus the received data could also be locally stored or recorded within a module 101.
The module 101 can send cryptographic parameters 126 from step 703 in a module encrypted data 403 using the shared secret key 129 and the module 101 can receive cryptographic parameters 126 from the server in a server encrypted data 504 using the shared secret key 129. In this manner, module 101 can securely communicate cryptographic parameters 126 without first deriving a module public key 111 and module private key 112. An agreed subset of cryptographic parameters 126a as illustrated in FIG. 1e may be necessary for module 101 to derive a compatible module public key 111 for the server 105. A system 100 and other systems illustrated herein can be flexible for supporting a wide range of modules 101 and servers 105, while remaining reasonably secure, by both (i) encrypting proposed cryptographic parameters 126 using the shared secret key 129 and (ii) agreeing on a subset of cryptographic parameters 126a as illustrated in FIG. 1e. 
After step 704, module 101 can then derive a first module public key 111 and a first module private key 112 pair, and record the values in a memory, which could comprise a nonvolatile memory such as flash memory 101w. In this manner, the key pair can be available to module 101 upon recovery from lost power. A module 101 could use (i) a step 515 depicted and described in connection with FIG. 5b in order to derive the key pair, and could also use the second set of cryptographic parameters 126 obtained through a step 704 above (which could comprise a subset of cryptographic parameters 126a). At step 515 in FIG. 7, module 101 can derive module private key 112 and a corresponding module public key 111 using (i) random number generator 128, (ii) the second set of cryptographic parameters 126 or the second subset of cryptographic parameters 126a from a step 704, (iii) cryptographic algorithms 141, and (iv) a key pair generation algorithm 141e. In an embodiment where the set of cryptographic parameters 126 are omitted from a step 704, then (i) in a step 515 in FIG. 7 module 101 could use the first set of cryptographic parameters 126 from step 703, or module 101 could use the set of cryptographic parameters 126 recorded in the activated eUICC profile 163b, which could also comprise the same or equivalent set of cryptographic parameters 126 recorded in the received eUICC profile 163a. The set of cryptographic parameters 126 recorded in the activated eUICC profile 163b could also comprise a subset of cryptographic parameters 126a as illustrated in FIG. 1e. Note that the use of an eUICC profile 163b is not required for a step 515.
Module private key 112 and corresponding module public key 111 can be derived in a step 515 according to a wide range of parameters 126, and can be selected from different algorithms, such as RSA 153 or ECC 154. Key derivation at step 515 could generate keys of different lengths, such as 2048 bits with RSA 153 or 283 bits with ECC 154, and other possibilities exist as well. If using ECC 154 to derive a pair of keys for module 101, a step 515 in FIG. 7 could also accommodate the use of different elliptic curves for compatibility with server 105, such as the use of odd-characteristic curves, Koblitz curves, etc. Additional example elliptic curves utilized in the generation or derivation of a key pair include the curves sect283k1, sect283r1, sect409k1, sect409r1, etc., which are identified as example curves in IETF RFC 5480, titled “Elliptic Curve Cryptography Subject Public Key Information”.
The ECC curve for a derived module public key 111 and module private key 112 can be specified in a subset of cryptographic parameters 126a from a step 704. Consequently, the parameters of keys generated by module 101 at a step 515 (including key length or algorithms utilized) may be selected based upon the requirements of the application and can be included in a set of cryptographic parameters 126. When deriving keys at a step 515, in an exemplary embodiment module 101 may also preferably utilize data from sensor 101f, radio 101z, a bus 101d, a physical interface 101a, memory 101e, and/or a clock 160 in order to generate a seed 128b for random number generator 128, or random number generator 128 could utilize these inputs directly. A random number can be input into key pair generation algorithm 141e in order to derive the module public key 111 and module public key 112 (with normally the module private key 112 being derived first with a key pair generation algorithm 141e). Since a module 101 may utilize a plurality of module 101 PKI key pairs during its lifetime, including the possibility of using multiple module private keys 112 concurrently, such as using different module private keys 112 for different purposes, in exemplary embodiments module 101 can also derive a module public key identity 111a for module public key 111 at a step 515 in FIG. 7. At subsequent steps where module 101 sends the module public key 111, the module 101 can also send the module public key identity 111a. In this manner, module 101 and a server 105 can properly track which module public key 111 is being used for any given set of communications with module 101 using PKI.
Upon key derivation at step 515 of FIG. 7, module private key 112 and module public key 111 can be recorded in a nonvolatile memory 101w. In an exemplary embodiment, module private key 112 is preferably not transmitted or sent outside module 101. Note that module 101's internal derivation, or processing or creation, of module private key 112 and corresponding module public key 111 can have many benefits. First, module private key 112 does not need to be recorded in any other location than within module 101, and thus may also be considered not shared. Recording module private key 112 only within module 101 avoids potential security risks of (i) storing or recording module private key 112 in other locations, such as with module provider 109, M2M service provider 108, or an installer or end user of module 101, and (ii) transferring module private key 112 from these other locations. A primary security risk from storage of module private key 112 outside module 101 is that unauthorized 3rd parties may gain access to the module private key 112.
Also note that over a potential lifetime of a decade or more of operation of module 101, each time a new module private key 112 may be required (for various potential reasons outlined above, including the use of new activated eUICC profiles 163b in embodiments where a module 101 uses an eUICC 163 to connect with a wireless network 102), the external recording and/or transferring of module private key 112 incurs a potential security risk. Security risks can be compounded if the external location records private keys 112 for a plurality of modules 101. Also, by internally generating private key 112 at a step 515, module 101 can overcome significant limitations and costs requiring the distribution of a pre-shared secret key Ki or K in the form of a SIM card or similar physical distribution of a pre-shared secret key.
At step 705, module 101 can send the module public key 111, and the module public key 111 could be sent to a server 105 in a message 208 that includes a module identity 110. In embodiments where a module 101 uses an eUICC 163 to connect with a wireless network 102, a module 101 can send the module public key 111 to a server 105 associated with the wireless network 102 in a step 705. The module 101 can also send the module public key identity 111a with the module public key 111 in a step 705. In an embodiment, the module 101 can send the module public key 111 to a server different than server 105 used in a step 704, and the different server could be a server associated with a certificate authority 118 an M2M service provider 108, or an eUICC subscription manager 164 if an eUICC 163 is used by module 101 to connect with a wireless network 102. The module identity 110 could be in the form of an encrypted module identity 110a, or a network module identity such as an IMSI or GUTI in embodiments where a module 101 uses an eUICC 163. The module public key 111 could be sent either as (i) plaintext or within a module encrypted data 403, or (ii) the shared secret key 129 or shared secret key 510 could be used as a symmetric key 127 with a symmetric ciphering algorithm 141b to encrypt the module public key 111. By sending the module public key 111 in a module encrypted data 403, a system 100 and other systems contemplated herein may be kept more secure, since other nodes besides server 105 would not be able to (i) read the module public key 111 or (ii) use the module public key 111 for sending module 101 unauthorized or fraudulent server encrypted data 504 with an asymmetric ciphering algorithm 141a and the module public key 111.
Although not depicted in FIG. 7, at step 705 server 105 could authenticate message 208 at step 705 that includes the module public key 111 in order to ensure that module public key 111 is properly associated with module identity 110 and that module public key 111 is not fraudulently submitted by another node or module 101 attempting to send the data. In an exemplary embodiment, at step 705 module 101 could use the steps for authentication of the message 208 containing module public key 111 using the authentication from a step 704. In an exemplary embodiment, module 101 could perform steps to authenticate with a server depicted and described in connection with step 1202 of FIG. 12 in U.S. patent application Ser. No. 14/064,618, filed Oct. 28, 2013 in the name of John Nix. Or, if module 101 sends module public key 111 in a step 705 at a sufficiently short period of time after step 704, such as, but not limited to, less than an exemplary minute after step 704, then the previous authentication from step 704 may still be applicable. In this case, the authentication of module 101 at a step 705 could comprise the authentication of module 101 from the prior step 704. Module 101 could also take the steps for authenticating a message 208 with the derived module public key 111 using a step 517 from FIG. 5. Module 101 could use the shared secret key 129 to conduct an authentication of a message 208 with module public key 111 in a step 705. Other possibilities exist as well without departing from the scope of the present invention for a module 101 to securely send a derived module public key 111 to a server 105 in a step 705.
At step 706, module, module 101 can begin utilizing the new module public key 111 and module private key 112 derived in a step 515 in FIG. 7, where new public key 111 was sent to a server 105 and authenticated in Step 705. At a step 706, module 101 could begin following normal operations of a data reporting steps 101x illustrated in FIG. 3. At step 706, module 101 can send a module encrypted data 403, where the module encrypted data 403 could include either (i) a symmetric key 127 ciphered with an asymmetric ciphering algorithm 141a and the server public key 114, or (ii) a server instruction 414 that could include a sensor measurement 305 or other data. If module encrypted data 403 at step 706 includes a server instruction 414, such as, but not limited to, an exemplary server instruction 414 depicted and described in connection with FIG. 6, then module 101 could send or receive a symmetric key 127 before step 706 and cipher data in the module encrypted data using the symmetric key 127. Although not depicted at step 706, module 101 can also send a module identity 110, an encrypted module identity 110a at a step 706.
For embodiments where module encrypted data 403 at step 706 includes data encrypted with an asymmetric ciphering algorithm 141a, the module 101 may also send a module digital signature 405 at a step 706, where the module digital signature 405 can be processed with the derived module private key 112 from a step 515 and a server 105 could verify the module digital signature 405 using the derived module public key 111 received by the server in a step 705. In another embodiment and before a step 706, module 101 and server 105 could conduct a key exchange illustrated in FIG. 9b in order to begin using a commonly shared symmetric key 127, where the key exchange uses the derived module PKI keys from a step 515. For embodiments where module 101 and server 105 conduct a key exchange according to FIG. 9b, the server public key 114 could comprise a “M2M service provider public key” 165b as depicted in FIG. 9b. According to a preferred exemplary embodiment, module 101 conducts a module key exchange algorithm 905 depicted and described in connection with FIG. 9b below in order to (i) derive a mutually shared symmetric key 127 with server 105, and (ii) send module encrypted data 403 in a step 706, where the module encrypted data 403 is encrypted using the derived symmetric key 127 and a symmetric ciphering algorithm 141b. In this manner, module 101 can conserve power by deriving the symmetric key 127 instead of sending or receiving the symmetric key 127 using an asymmetric ciphering algorithm 141a, which would require more power and time being active. In order to utilize a module key exchange algorithm 905 to derive a symmetric key 127 before a step 706, module 101 could send or receive a key exchange token 906 with server 105 before conducting the module key exchange algorithm 905.
At step 707, module 101 can receive a response 209, where the response 209 includes server encrypted data 504, and the server encrypted data 504 can include a module instruction 502. In this step 707 a server 105 can utilize the new module public key 111, resulting from the key generation by module 101 in a step 515 above in FIG. 7, to encrypt server encrypted data 504 in one of two ways. First, server 105 can encrypt server encrypted data 504 using an asymmetric ciphering algorithm 141a by ciphering with the new module public key 111 (where the server encrypted data 504 could include a symmetric key 127). Second, server 105 can encrypt server encrypted data 504 using a symmetric ciphering algorithm 141b by utilizing a key derivation function 141f including steps for ECDH 159 and (i) the new module public key 111 and (ii) the server public key 114 in order to derive a commonly shared symmetric key 127, which could comprise a derived shared secret key 129b. In this second instance, module 101 can decrypt server encrypted data 504 in step 707 using a symmetric ciphering algorithm 141b and the commonly shared, derived symmetric key 127 comprising a derived shared secret key 129b. Module instruction 502 at a step 707 could comprise an “acknowledgement” that a message 208 sent in a step 706 was properly received. Other possibilities exist as well for a module 101 to receive and process a server encrypted data 504 with a module instruction 502 in a step 707.
At step 708, module 101 or server 105 can determine or evaluate if a new module private key 112 and module public key 111 are required for continued operation. Another node associated with M2M service provider 108 besides server 105 could also determine if the use of new PKI keys are desirable in a step 708. Exemplary reasons for the generation of new keys by a module 101 were described at the beginning to this FIG. 7. One reason could be the expiration of a certificate 122 for module 101, or equivalently the expiration of a time-to-live value for a module public key 111 if module public key 111 is not recorded in the form of a certificate 122. A second exemplary reason could be that module 101 may wish to connect with a new wireless network 102 that requires the use of PKI techniques for authentication, but also a different set of cryptographic parameters 126 or algorithms in order for module 101 to communicate through a new wireless network 102. In an exemplary embodiment, a set of cryptographic parameters 126 for a server 105 may change or be different than with a previous server 105, such as, but not limited to, (i) using a different elliptic curve or a different set of asymmetric ciphering algorithms 141a, or (ii) requiring longer key lengths. Module 101 may need to derive at a step 708 a new set of a compatible module public key 111 with a corresponding module private key 112. A third exemplary reason could be that module 101 prefers to use a different received eUICC profile 163a in order to connect with a different wireless network 102 than the wireless network 102 utilized for communication in a step 705 or step 706.
Other examples for reasons that a module 101 may need new public/private keys after installation with a monitored unit 119 exist as well, and any could be a reason for module 101 to determine to utilize new public/private keys. If module 101 and/or a server 105 determine that new keys are not required at step 708, module 101 can then proceed to a step 309 and wait for a specified interval before taking further action. As illustrated in FIG. 7, the further action could comprise returning to a step 706 and the module could continue to periodically report data regarding a monitored unit 119 in the form of periodically sending a message 208 to server 105, and the message 208 could contain a sensor data 305, or other data for the remote monitoring and/or control of a monitored unit 119. In an exemplary embodiment, the determination at a step 708 could be made at other times as well, such as before a step 707 or a step 706. Upon return to a step 706 and step 706, module 101 could continue to use the module PKI keys derived in a step 515 in order to send a module encrypted data 403 and receive a server encrypted data 504.
Either a module 101 or a server 105 could determine if the use of new module 101 PKI keys are preferred or desirable in a step 708. As contemplated herein, the term “PKI keys” can refer to a pair of keys comprising a module public key 111 and a module private key 112. In the embodiment where a server 105 or another node associated with M2M service provider 108 determines or evaluates that the use of new module 101 PKI keys are preferred or required in a step 708, then at a step 607 a server 105 could send a signal to module 101 to derive new PKI keys. An exemplary signal for module 101 to derive new PKI keys in a step 607 could be in the form of an exemplary response 209 illustrated in FIG. 6, where the response 209 includes a module instruction 502 of “derive new PKI key pair”. If a module 101 determines on its own (i.e. without receiving a signal from a server 105 for deriving new keys), then step 607 may be omitted, and otherwise a step 607 can otherwise be useful or required in order to signal that a module 101 should derive new PKI keys. In an exemplary embodiment, a step 607 may require sending the module instruction 502 of “derive new PKI key pair” within a response 209, where module 101 may previously have sent a message 208. The reason can be that a module 101 may operate behind a firewall 104 or periodically sleep, and in this case a server 105 may not be able to send a module 101 the module instruction 502 at arbitrary times, but must wait until after module 101 first sends a message 208 before sending the module instruction 502 of “derive new PKI key pair” in a response 209.
A step 607 can also comprise a module 101 receiving a third set of cryptographic parameters 126 or a subset of cryptographic parameters 126a. A third set of cryptographic parameters 126 or a subset of cryptographic parameters 126a can also be optionally omitted from a step 607 and in this embodiment a prior set of cryptographic parameters 126 or a subset of cryptographic parameters 126a, such as the parameters 126 (i) received by a module 101 in a step 704 above, or (ii) initially recorded in a step 703 could apply. In a step 607 a module 101 can send a set of cryptographic parameters 126 and receive a third subset of cryptographic parameters 126a. Or, a module can receive a third set of cryptographic parameters 126 and send a subset of cryptographic parameters 126a. The subset of cryptographic parameters 126a could comprise a (i) single value such as specifying a named curve within an ECC standard curve 138, a modulus to use with an RSA algorithm 153, or a time value for a new module public key 112, or (ii) multiple values such as two or more selected from an exemplary subset of cryptographic parameters 126a illustrated in FIG. 1e. Note that in a step 607 the module instruction 502 of “derive new PKI key pair” or a similar signal could be received by a module 101 in a separate packet than either a set of cryptographic parameters 126 or a subset of cryptographic parameters 126a. 
In addition, in a step 607 the module instruction 502 of “derive new PKI key pair” or a similar signal could be received by a module 101 either as plaintext in a packet or within a server encrypted data 504. Further, in a step 607 the third set of cryptographic parameters 126 or the subset of cryptographic parameters 126a could be received by a module 101 either as plaintext in a packet or within a server encrypted data 504. As illustrated in FIG. 7, the set of cryptographic parameters 126 or the subset of cryptographic parameters 126a could comprise a 3rd set of cryptographic parameters 126, and the 3rd set of cryptographic parameters 126 may be the same or different than a 2nd set of cryptographic parameters 126 received in a step 704. In an exemplary embodiment, a step 607 comprises receiving the third set of cryptographic parameters 126 and a module instruction 502 in the form of a received eUICC profile 163a for an eUICC 163. The data received by module 101 at a step 607 in FIG. 7 could include a second received eUICC profile 163a, for embodiments where a module 101 uses an eUICC 163 to connect with a wireless network 102, where the second received eUICC profile 163a can be different than a first eUICC profile 163a described for a step 703 above.
At step 709 the module 101 can use the third set of cryptographic parameters 126 received in a step 607 to derive a second module private key 112 and a second module public key 111. Module 101 could use a step 515 in order to derive the second module private key 112 and second module public key 111 at a step 709. In embodiments where a module 101 uses an eUICC 163 to connect with a wireless network 102, a step 709 could comprise module 101 deriving a second module PKI key pair for use in a second activated MNO network credentials (different from a first set of activated MNO network credentials from a step 703 above in FIG. 7, if an eUICC 163 is utilized), and the third set of cryptographic parameters 126 in a step 709 could comprise the set of cryptographic parameters 126 received in the received eUICC profile 163a from a step 607 above. In other embodiments, the use of an eUICC 163 by module 101 is not required in a step 709, and a step 709 to derive new module PKI keys can be independent of the presence or use of an eUICC 163. In other words, a module 101 and a server 105 can use (i) some embodiments of the present invention illustrated in FIG. 7 and other Figures herein independently of the presence of an eUICC 163 and related profiles, while (ii) other embodiments may use an eUICC 163 and related profiles.
At step 709, module 101 can derive the second module private key 112 and a corresponding second module public key 111 using (i) random number generator 128, (ii) the third set of cryptographic parameters 126 or the third subset of cryptographic parameters 126a from a step 607, (iii) cryptographic algorithms 141, and (iv) a key pair generation algorithm 141e. In an embodiment where the second set of cryptographic parameters 126 are omitted from a step 607, then in a step 709 module 101 could use either (i) the first set of cryptographic parameters 126 from step 703 or (ii) the second set of cryptographic parameters 126 or 126a from a step 704. In a step 709 a module 101 can also derive and a assign a second module public key identity 111a to be associated with the second module public key 111, where the second module public key identity 111a can be used to identify and select the second module public key 111 from a first module public key 111 potentially from a step 515 above. In other words, a second module public key 111 can be associated with a second module public key identity 111a and a first module public key identity can be associated with a first module public key identity 111a. 
According to the set of cryptographic parameters 126 or 126a used in a step 709, in an exemplary embodiment the module PKI keys derived in a step 709 can be associated with a different asymmetric ciphering algorithm 141a than the module PKI keys derived in a step 515 in FIG. 7. For example, the first module PKI keys in a step 515 in FIG. 7 could utilize a first ECC standard curve 138, while the second module PKI keys in a step 709 could use a second ECC standard curve 138. Or, the first module PKI keys in a step 515 in FIG. 7 could utilize an RSA algorithm 153, while the second module PKI keys in a step 709 could use an ECC algorithm 154. In another embodiment at step 709, the first module PKI keys in a step 515 in FIG. 7 could utilize an RSA algorithm 153 with a shorter key length, such as, but not limited to, an exemplary 1024 bits, while the second module PKI keys in a step 709 could use an RSA algorithm 153 with a longer key length such as, but not limited to, an exemplary 2048 bits. Further, the first module PKI keys in a step 515 in FIG. 7 and the second module PKI keys in a step 709 could use the same algorithm and key length. Other possibilities for differences or similarities between the first module PKI keys in a step 515 and the second module PKI keys in a step 709 are possible as well without departing from the scope of the present invention.
After deriving the second module PKI keys in a step 709, at step 710 the module 101 can send the second module public key 111 with the module identity 110 to a server 105. In embodiments where a module 101 uses an eUICC 163 to connect with a wireless network 102, the module 101 can send the second module public key 111 associated with an activated eUICC profile 163b with a network module identity such as an IMSI or GUTI to a server 105 associated with (i) wireless network 102 and/or (ii) eUICC subscription manager 164. In exemplary embodiments, the second module public key 111 can be sent with the second module public key identity 111a. The module 101 can send the data in a message 208. In an exemplary embodiment the module 101 can send (i) the second module public key 111 and a module identity 110, and (ii) authenticate or verify data sent by module 101 in a step 710 using the first module private key 112 from a step 515 in FIG. 7. The authentication or verification of data sent by module 101 in a step 710 could comprise verifying or authenticating data sent with the second module public key 111, such as verifying or authenticating module identity 110. Or the authentication or verification of data sent by module 101 in a step 710 could comprise verifying or authenticating the second module public key 111, and other possibilities exist for a module 101 to send the second module public key in an authoritative manner.
In an exemplary embodiment, in a step 710 the module 101 can use the first module private key 112 to verify or authenticate the second module public key 111 sent using at least one of several sub-steps. The sub-steps at a step 710 to verify the second module public key 111 using the first module private key 112 could comprise any of (i) sending the second module public key 111 and a module identity 110 with or in a module encrypted data 403 that uses a symmetric ciphering algorithm 141b, where the symmetric key 127 for encrypting and decrypting the module encrypted data 403 at step 710 could previously be communicated before step 710 using the first module private key 112 (such as, but not limited to, a module 101 receiving the symmetric key 127 from a server 105 in a server encrypted data 504, where the server encrypted data 504 was deciphered with an asymmetric ciphering algorithm 141a and the first module private key 112), (ii) sending the second module public key 111 and module identity 110 with a module digital signature 405 where the module digital signature 405 is calculated or processed by module 101 using the first module private key 112 from a step 515 in FIG. 7, (iii) using a derived shared secret key 129b with a message digest authentication for verifying a sent message 208 with the second module public key 111 at step 710, where the derived shared secret key 129b was processed using a key derivation function 141f and the first module private key 112, and/or (iv) using a derived shared secret key 129b as a symmetric key 127 for encrypting data sent with the second module public key 111, where the derived shared secret key 129b was processed using a key derivation function 141f and the first module private key 112.
Other possibilities exist as well without departing from the scope of the present invention for using the first module private key 112 from a step 515 in order for a module 101 to verify or authenticate data sent with the second module public key 111 at a step 710. As illustrated in FIG. 7, after step 710, the module 101 can return to a step 706 and continue regular operation such as, but not limited to, collecting sensor data 305 and sending the data periodically in a module encrypted data 403. In embodiments where a module 101 uses an eUICC 163, module 101 could send and receive application data with a second wireless network 102 after completing step 710. Upon returning to step 706, the module encrypted data 403 could use the second module PKI keys derived in a step 709. In embodiments where module 101 returns to step 706, depicted values for subsequent steps could increment, such upon returning to step 709 for a second time, then the depicted values for “second module public key” and “3rd parameters” could become “third module public key” and “4th parameters” at the second iteration of step 709, etc.
Benefits of using the first module private key 112 in authentication of the second module public key 111 at a step 710 include a server 105 could use the first module public key 111 received by server 105 in a step 705 in order to authenticate or verify the correct module 101 sends the second module public key 111. In addition, module 101 may communicate with a plurality of servers 105, including servers from different mobile network operators 108 over time. The plurality of servers 105 could share the first module public key 111 such that when a step 710 occurs, module 101 may send the second module public key 111 and module identity 110 to a different server 105 than the server 105 from a step 705 or step 706. In embodiments where a module 101 uses an eUICC 163 in order to connect with a wireless network 102, either (i) different wireless networks 102 or (ii) an eUICC subscription manager 164 could share the first module public key 111 in order to authenticate the second module public key 111 in a step 710 of FIG. 7.
In other words, the substeps described in connection with a step 710 as described in the preceding three paragraphs could be conducted by a server 105 using the first module public key 111 received in a step 705 in order to authenticate the second module public key 111 from a step 709 (and a module 101 could use the first module private key 112 for the authentication of the second module public key 111). By module 101 authenticating or verifying data with the second module public key 111 using the first module private key 112, the different server 105 could access and use the first module public key 111 in authentication or verification steps performed by the different server 105 in order for the server to securely receive the second module public key 111. Security for a server 105 in future steps, such as securely receiving future messages 208 after a step 710 can depend on a server 105 recording the correct second module public key 111 for a module 101, including preventing unauthorized or fraudulent parties from attempting to send the second module public key 111.
In an exemplary embodiment, the module identity 110 in a step 710, and other steps for communication a module identity 110 in FIG. 7, could comprise an encrypted module identity 110a. In this manner, the module identity 110 could be securely transmitted across a public network such as the IP Network 107. The second module public key 111 in a step 710 could be sent in a module encrypted data 403, such that third parties may not reasonably be able to read the plaintext second module public key 111. As noted elsewhere herein, any given module public key 111 may not need to be publicly shared and could remain confidential for an M2M service provider 108, and in this manner the security for communications between module 101 and server 105 can be further increased, since a potential attacker could be prevented from having reasonable access to a module public key 111.
Further, module 101 could use a plurality of module public keys 111 for different purposes, including different module public keys being associated with different asymmetric ciphering algorithms 141a. A first module public key 111 could be used with a first wireless network 102, a second module public key 111 could be used for verifying module digital signatures 405, and a third module public key 111 could be for a different M2M service provider 108, etc. The use of different module public keys 111 could be specified using a module public key identity 111a. In exemplary embodiments, a first subset of the module public keys 111 may be sent by a module 101 in a module encrypted data 403 and a second subset of the module public keys 111 could be sent by the module 101 as plaintext within a datagram 601a. As illustrated in FIG. 7, the collection of steps from step 702 through step 704 can comprise sub-steps for a step 711. A step 711 may be utilized in FIG. 10 below.
FIG. 8
FIG. 8 is a simplified message flow diagram illustrating an exemplary message sent by a module, wherein the message includes a derived module public key, in accordance with exemplary embodiments. As discussed in FIG. 5b, there can be cases where module 101 derives a new module public key 111 and new module private key 112. On example would be the initial creation of the key pairs by module 101, and many other examples could exist as well. FIG. 8 can illustrate an exemplary format and contents of a message 208 for steps 710 of FIG. 7. This exemplary message 208 can also help to illustrate the significant differences from conventional technology and improvements for efficient and secure communications by utilizing embodiments contemplated herein. Since a message 208 illustrated in FIG. 8 could be related to more than one module public key 111, as depicted and described herein the new module public key 111 can be referred to as new module public key 111′ and the prior applicable module public key 111 can be referred to as module public key 111. Likewise, a new module public key identity 111a can be referred to as a new module public key identity 111a′, and the prior applicable module public key identity 111a can be referred to as module public key identity 111a. 
A message 208 illustrated in FIG. 8 using a step 710 from FIG. 7 can include (i) sending new module public key 111′, a module public key identity 111a′, a module identity 110, a server instruction 414, a security token 401, a subset of cryptographic parameters 126a associated with (i) the new module public key 111′ and/(ii) or cryptographic algorithms 141 for using the new module public key 111′. Exemplary cryptographic parameters 126a illustrated in FIG. 8 include (i) a secure hash algorithm 141c to utilize in signatures, which could comprise the SHA 256 algorithm as shown (which may also be known as the SHA-2 algorithm), (ii) a selected elliptic curve for use with ECC algorithms 154 or a modulus to use with RSA algorithms 153, and (iii) a time-to-live value for the new module public key 111′, such as, but not limited to, the illustrated “time to live” value of 1 year shown in FIG. 8. The time value for the validity of new module public key 111′ could alternatively be specified in a set expiration date. Other values associated with cryptographic algorithms 141 could be included in a set of cryptographic parameters 126 as well, and the illustrated values are intended to be exemplary instead of limiting. In exemplary embodiments, the set of cryptographic parameters 126 in a message 208 could comprise a set of cryptographic parameters 126 depicted and described in connection with FIG. 1e. Or, module 101 could send a set of cryptographic parameters token 126c to identify a set of cryptographic parameters 126 instead of sending the complete list of cryptographic parameters 126. Note that a set of cryptographic parameters 126 or 126a or token 126c could be optionally omitted in the message 208 illustrated in FIG. 8 when a prior message 208 or step had negotiated or established the set of cryptographic parameters 126 or 126a to use with the new module public key 111′.
Additional values or fields within a message 208 associated with communicating a new module public key 111′ with a server 105 could include a server instruction 414 of “new public key”. This server instruction 414 could inform server 105 to utilize the new module public key 111′ within the message 208. Module public key identity 111a′ can include a sequence number or identity for the new module public key 111′, such that module 101 or server 105 can properly reference and/or record the key from a plurality of module public keys 111 that could be associated with module identity 110. Although module public key identity 111a′ is illustrated as a separate field in server instruction 414, module public key identity 111a′ could optionally be included in a set of cryptographic parameters 126, such that the value within cryptographic parameters 126 specifies a current sequence number of module public key identity 111a′ for the new module public key 111′ included in a message 208. In addition, although the module public key identity 111a′ illustrated in FIG. 8 could be a sequence number, the module public key identity 111a′ could also optionally be globally unique. For example, the module public key identity 111a′ could comprise a combination of a unique serial number from a module 101 and then a sequence number. With a globally unique module public key identity 111a, a server 105 reading the module public key identity 111a could determine a module 101 with a module identity 110 associated with any given module public key identity 111a. 
Other fields and features within a message 208 as illustrated in a FIG. 8 can be similar or equivalent to the fields presented in FIG. 6. In an exemplary embodiment, the new module public key 111′ can be transmitted by a module 101 using at least one of (i) channel coding 406 for a body 602 of message 208 and/or (ii) forward error correction such that message 208 could be transmitted multiple times concurrently in order to increase the probability of receipt by a server 105. In an exemplary embodiment, a message 208 containing the new module public key 111′ could be sent by module 101 three times concurrently, and other possibilities exist as well. In an exemplary embodiment, the module identity 110 could be included within an encrypted module identity 110a. Module 101 could use a secret symmetric ciphering algorithm 161 to encrypt the module identity 110. In another embodiment illustrated in FIG. 8, module identity 110 could be sent as plaintext within the message 208 that includes the new module public key 111′.
For a message 208 in FIG. 8 comprising a message for a step 710 in FIG. 7, each of (i) destination IP:port number 207, (ii) parameters 126, and (iii) symmetric key 127 could be updated by server 105 using a module instruction 502 within a server encrypted data 504 before message 208 illustrated in FIG. 8 is transmitted or sent by module 101. After receiving message 208, server 105 can use the module identity 110 illustrated in a body 602 of FIG. 8 to select at least one of (i) a symmetric key 127 associated with module identity 110, where the symmetric key 127 could comprise a session key, and/or (ii) a prior module public key 111 associated with the module identity 110. The symmetric key 127 could be established in steps such as a step 706 or the prior module public key 111 (i.e. not the new module public key 111′ in FIG. 8) sent in a step 705. The server 105 can use the selected symmetric key 127 or selected prior module public key 111 to authenticate message 208. As described in step 710 of FIG. 7 and elsewhere herein, a server 105 may preferably authenticate message 208 that includes new module public key 111′ in order to confirm that module public key 111 originated from physical module 101 with a hardware module identity 110 (as opposed to being an imposter submitting the new module public key 111′). In one example, successfully decryption the module encrypted data 403 using the symmetric key 127 would authenticate or verify the message 208, since only the valid and correct module 101 could reasonably have access to the symmetric key 127 to encrypt the new module public key 111′. Other possibilities exist as well for a module 101 to authenticate a message 208.
Although not depicted in FIG. 8, in an exemplary embodiment new module public key 111′ could also be sent in a message 208, where the new module public key 111′ and parameters 126 (if present) can be included in plaintext format within a datagram 601a. The security of a system 100 and other systems illustrated herein can be further increased by both (i) ciphering new module public key 111′ and the set of cryptographic parameters 126, and (ii) only sharing the new module public key 111′ in a confidential manner with server 105 and/or a set of servers 1010. If module 101 needed a module public key 111 for other purposes, such as, but not limited to, obtaining a certificate 122, then a second, publicly disclosed module public key 111 could be utilized to authenticate a message 208 from FIG. 8 that is sent as plaintext without symmetric ciphering 141b, where the second module public key 111 is different than and sent before the new module public key 111′ that is sent to a server 105 in a module encrypted data 403.
Although not depicted in FIG. 8, in an exemplary embodiment, new module public key 111′ can be authenticated with server 105 using a module digital signature 405. When message 208 illustrated in FIG. 8 comprises a message for a step 710 illustrated in FIG. 7, such that a prior module public key 111 has previously been sent to server 105 such as in a step 705, then message 208 could include a module digital signature 405 using the previous module private key 112 (i.e. not the new module private key 112 associated with the new module public key 111′ in the message 208 shown in FIG. 8). In another embodiment, module digital signature 405 could be omitted, and message 208 with new module public key 111′ could be authenticated using a message digest algorithm and a shared secret key 129, where the shared secret key could be sent using a step 706 or 707 from FIG. 7. Other possibilities for a module 101 to send a new module public key 111′ in a message exist as well without departing from the scope of the present invention.
FIG. 9a 
FIG. 9a is a graphical illustration of public keys, private keys, and a key derivation algorithm, in accordance with exemplary embodiments. A module 101 can include a module private key 112, which can be associated with a module public key 111. The module private key 112 and module public key 111 can comprise a public key infrastructure (PKI) key pair for module 101. The M2M service provider 108 can record the module public key 111 along with an module identity 110, such that the M2M service provider 108 can properly associate one of a plurality of module public keys 111 with the proper module 101. Although not depicted in FIG. 9a, a M2M service provider 108 could record the module public key 111 and an associated module identity 110 in a database. The use of, source, and additional details regarding a module public key 111 and module private key 112 are also depicted and described in connection with FIG. 1a, FIG. 1c, and other figures above.
The M2M service provider 108 could also be associated with a network private key 165a and a network public key 165b, which could comprise a PKI key pair for the M2M service provider. The network private key 165a could comprise a server private key 105c and the network public key 126b could comprise a server public key 114. The M2M service provider 108 could process or derive the PKI key pair using steps and algorithms equivalent to the steps and algorithms for a module 101 to obtain the module public key 111 and module private key 112. The PKI keys depicted in FIG. 9a could be processed using RSA algorithms or elliptic curve cryptography (ECC) algorithms, and other possibilities exist as well for the format of PKI keys without departing from the scope of the present invention. The public keys in FIG. 9a can comprise keys recorded in an X.509 certificate, although the use of an X.509 certificates with public keys 111 and 165b are not required. The public key 111 and 165b in the form of an X.509 certificate can optionally be signed by a certificate authority 118. The network public key 165b can be recorded in nonvolatile memory of module 101 such as memory 101w. The M2M service provider 108 could send the network public key 165b to the eUICC subscription manager 164 from FIG. 1, and the eUICC subscription manager 164 could include the network public key 165b in a profile for the eUICC 163.
As illustrated in FIG. 9a, the M2M service provider 108 and module 101 can both record a key derivation function 141f. Exemplary key derivation functions 141f could support a Diffie Hellman key exchange, an Elliptic Curve Diffie Hellman (ECDH) key exchange (ECDH), or similar algorithms for each node to mutually derive a key using public and private keys. For embodiments where (A) module public key 111, module private key 112, network public key 165b, and network private key 165a utilize (i) elliptic curve cryptography (ECC) and (ii) a common, shared elliptic curve, then (B) a key derivation function 141f in FIG. 9a can comprise an algorithm for conducting an ECDH key exchange 159. The use of an ECDH key exchange 159 was also described and contemplated within a set of cryptographic algorithms 141. For embodiments where a key derivation function 141f supports a Diffie Hellman key exchange, the key derivation function 141f could record a multiplicative group of integers modulo p, where p is prime, and g is a primitive root mod p. In exemplary embodiments, p can be sufficiently large, such as, but not limited to, and exemplary prime number of at least 250 digits, and g can be a small number, such as, but not limited to, the number 5. In exemplary embodiments, additional values pertaining to the operation of a key derivation function 141f can be transferred between two nodes using a key exchange token 906 as described in a FIG. 9b and FIG. 10 below.
FIG. 9b 
FIG. 9b is a graphical illustration of deriving a symmetric key using public keys, private keys, and a key derivation algorithm, in accordance with exemplary embodiments. A M2M service provider 108 could process a M2M service provider key exchange algorithm 904 in order to output or determine a symmetric key 127. A module 101 could process a module key exchange algorithm 905 in order to output or determine the same symmetric key 127. The M2M service provider key exchange algorithm 904 and the module key exchange algorithm 905 could include a key derivation function 141f, and a key derivation function 141f is also depicted and described in connection with FIG. 9a above and FIG. 1 d. The M2M service provider 108 and module 101 could share or communicate a key exchange token 906 in order to operate the key exchange algorithm 905. In this manner, a module 101 and a M2M service provider 108 could mutually derive or share the symmetric key 127 without M2M service provider 108 transmitting or sending the symmetric key 127, even in an encrypted form such as a symmetric key 127 encrypted with an asymmetric ciphering algorithm 141a. 
For a M2M service provider key exchange algorithm 904, a M2M service provider using a server 105 could input the private key 165a, the module public key 111, and a key exchange token 906 into a key derivation function 141f in order to output the symmetric key 127. Note that the key derivation function 141f in both a M2M service provider key exchange algorithm 904 and a module key exchange algorithm 905 can include additional or separate processing steps than those contemplated in a Diffie-Hellman key exchange and an ECDH key exchange 159. Additional steps than those contemplated in a Diffie-Hellman key exchange or ECDH key exchange 159 for a key derivation function 141f include transforming a key output by these key exchange protocols into a key length and format compatible and suitable for a symmetric key 127. In a key derivation function 141f, the output of a Diffie-Hellman key exchange and an ECDH key exchange 159 could be input into a secure hash algorithm, such as SHA-256, which could then be truncated to select a 128 bit or 192 bit symmetric key 127 using a key derivation function 141f. 
For a M2M service provider key exchange algorithm 904, the security key exchange token 906 can depend upon the algorithm used in a key derivation function 141f. For embodiments where key derivation function 141f comprises a Diffie-Hellman key exchange, the key exchange token 906 can comprise integer values of p and g. Or, with a Diffie-Hellman key exchange the security key exchange token 906 sent from a M2M service provider 108 to module 101 could comprise a value equal to g^a mod p where (x) the values or p and g have been previously shared between M2M service provider 108 and module 101, and (y) the value “a” can comprise the network private key 165a. A security key exchange token 906 received by M2M service provider 108 for input into a key derivation function 141f for a module 101 could comprise a value of g^b mod p, where b comprises the module private key 112. For embodiments where key derivation function 141f comprises an ECDH key exchange 159, the key exchange token 906 can a common base point G. The base point G could also be (i) recorded in an eUICC 163 in a profile 163a, or (ii) sent from a M2M service provider 108 to module 101, or (iii) sent from the module 101 to the M2M service provider 108. Other algorithms besides an ECDH or Diffie Hellman key exchange can be utilized as well for a key derivation function 141f, including a key exchange according to the American National Standards Institute (ANSI) standard X-9.63 160. A key exchange token 906 could include a number or value associated with these other algorithms for a key derivation function 141f. 
For a module key exchange algorithm 905, a module 101 could input the module private key 112 and the network public key 165b into a key derivation function 141f. Note that the input into the key derivation function 141f could also optionally include a key exchange token 906. The key derivation function 141f in a module key exchange algorithm 905 could accept the input and output a symmetric key 127. The key derivation function 141f in a module key exchange algorithm 905 could be equivalent to the key derivation function 141f in a M2M service provider key exchange algorithm 904 described above. The key exchange token 906 in a module key exchange algorithm 905 could comprise a value similar to the key exchange token 906 used in a M2M service provider key exchange 904 described above. In a Diffie-Hellman key exchange for a key derivation function 141f in a module key exchange algorithm 905, the key exchange token 906 can comprise a value of either (i) integers p and g as described in a M2M service provider key exchange 904, or (ii) number g^a mod p. In an ECDH key exchange 159 for key derivation function 141f in a module key exchange algorithm 905, the key exchange token 906 can comprise a base point G. Other possibilities exist as well for a key exchange token 906 without departing from the scope of the present invention. A key derivation function 141f can output a symmetric key 127 that is equal to the symmetric key 127 in an M2M service provider key exchange algorithm 904. Other possibilities exist as well for the use of PKI keys and tokens in key exchange algorithms for those of ordinary skill in the art without departing from the scope of the present invention.
FIG. 10
FIG. 10 is a simplified message flow diagram illustrating an exemplary system with exemplary data transferred between a module and a set of servers, in accordance with exemplary embodiments. System 1000 may comprise a module 101 and a set of servers 1010, where the set of servers 1010 can include a plurality of servers 105 and a shared module database 105k. FIG. 10 illustrates module 101 communicating with a server 105, depicted as “server A” 105, although a module 101 could communicate with other servers within a set of servers 1010 as well. The set of servers 1010 could be associated with an M2M service provider 108 and the set of servers 1010 could operate in a coordinated manner through a network. Although not depicted in FIG. 10, module 101 could access a wireless network 102 and the IP Network 107 illustrated in FIG. 1a in order to send data to and receive data from a server 105 within a set of servers 1010.
As illustrated in FIG. 10, a module 101 can communicate with a server 105 using the steps and datagrams illustrated in other figures, including sending a message 208, receiving a response 209, using steps 711, 607, 709, and/or 710 as depicted and described in connection with FIG. 7. FIG. 10 illustrates some of many potential combinations of using these individual steps for an efficient and secure system. Other messages 208 may potentially flow before and/or after a “first message” 208 at a step 1001. This terminology of “first message”, “second response”, “second public key”, etc. contemplated in various Figures herein may refer to the “first message”, “second response”, “second public key”, “first set of parameters”, etc. described in the illustrated flows within each Figure. Other messages, responses, keys, and parameters may be communicated before and/or after a depicted “first message”, “second response”, “second public key”, etc. The depicted elements for Figures herein can comprise subsets of all messages, responses, keys, etc. that may also flow, and the subsets can depict various embodiments contemplated herein.
In exemplary embodiments, FIG. 10 illustrates the establishment of secure communication between a module 101 and a set of servers 1010 for the case where (i) an existing, authenticated module public key 111 is available from external servers, and (ii) the existing module public key 111 can be used to send parameters for the module 101 to derive a new module PKI key pair. As one example, the optional step 711, before a step 1001, could be used to authoritatively record a module public key 111 with external servers such as those external servers shown in a step 1002 in FIG. 10. The optional step 711 could include module 101 recording an initial module public key 111b that is not derived by module 101, but rather loaded into module 101 by a manufacturer, distributor, or end user, and (a) the initial module public key 111b could be used by a module 101 and a server 105 to authenticate and/or encrypted subsequent communications related to (b) a subsequent derived module public key 111. After the derived module public key 111 has been successfully authenticated or recorded by a server 105 or a set of servers 1010, then a server 105 or set of servers 1010 can begin using the derived module public key 111 for subsequent authentication and/or encryption for communication with a module 101, instead of continuing to use the initial module public key 111b. 
In exemplary embodiments, (i) an initial module private key 112b could be recorded in a nonvolatile memory for module 101 prior to a step 1001 illustrated in FIG. 10, possibly using a step 711, and (ii) a set of servers 1010 could use an initial module public key 111b associated with the initial module private key 112b in order to establish initial secure communications with a module 101 such as using a step 1004 to transfer a symmetric key 127 for ciphering a new, second set of cryptographic parameters 126, and then (iii) a module 101 could receive the ciphered second set of cryptographic parameters 126 with subsequent exemplary steps illustrated in FIG. 10 to derive additional module PKI keys, and (iv) establish secure communication with a set of servers 1010 using the second set of cryptographic parameters 126 and the derived module PKI keys.
In an embodiment where module 101 records a “base” certificate 122 (with a corresponding “base” module private key 112) which are included with a module 101 by a manufacturer or a module provider 109. A M2M service provider 108 can use the “base” certificate 122 to communicate further sets of cryptographic parameters 126 for deriving additional module PKI keys. The initial set of cryptographic parameters 126 and an initial module public key 111b could be recorded in the “base” certificate 122, and the exemplary use of cryptographic parameters 126 in a certificate 122 is illustrated in FIG. 1f. The initial set of cryptographic parameters 126 could also be referred to as a “base” set of cryptographic parameters 126. The module manufacturer, module provider 109, M2M service provider 108, and/or wireless network 102 could agree on a common initial set of cryptographic parameters 126 (such as, but not limited to, agreeing that initial module PKI keys could be based on RSA and a length of 2048 bits). By agreeing to a common initial set of cryptographic parameters 126, different modules 101 from different manufactures could initially interoperate with different module providers 109 and/or M2M service providers 108 using the initial, “base” parameters. The entities such as the M2M service provider 108 and/or wireless network 102 could use the “base” or initial set of cryptographic parameters 126 with the “base” certificate 122 to establish secure communications where subsequent, different sets of cryptographic parameters 126 for deriving new module PKI keys could be securely communicated and/or negotiated.
A first optional step 711 can comprise series of sub-steps comprising a step 702, 703, and 704 as depicted and described in connection with FIG. 7. Note that the use of an optional step 711 can be omitted, and other preliminary steps and communications could take place between a module 101 and a set of servers 1010 before a module 101 performs a step 1001. In another exemplary embodiment, a module 101 may have used the data from a step 711 in communicating with a different set of servers (not shown) than the set of servers 1010 illustrated in FIG. 10, and the set of servers 1010 illustrated in FIG. 10 may not have access to data from the different set of servers (not shown). The sub-steps for a step 711 can include a module distribution and installation step 702. As contemplated herein, the term “installation” can also refer to a subset of steps conducted by an end user or technician for activation, such that a module 101 performs initial steps to become operable upon completion of the “installation” or activation. In one embodiment, module 101 can comprise a mobile phone such as a smartphone and in this case “installation” in a step 702 within a step 711 can comprise an end user powers up the mobile phone or smartphone for an initial time. Also, in an exemplary embodiment where the optional step 711 is omitted, no data flows between a module 101 and a set of servers 1010 until the first message 208 at a step 1001 illustrated in FIG. 10.
After a sub-step 702 in an optional step 711 in FIG. 10, the next sub-step can comprise a sub-step 703 as depicted and described in FIG. 7. In this sub-step 703, a module 101 can record in nonvolatile memory a shared secret key 129, a first set of cryptographic parameters 126, and a server address 207. As discussed above, a server address 207 could comprise a server name 206 in a step 703, which could subsequently be resolved via DNS into an IP address 106 for a server 105 (or a plurality of IP addresses 106 for a set of servers 1010). The use of a shared secret key 129 for a step 703 is depicted and described in connection with FIG. 7. Note that for the purposes of the present invention contemplated herein, a shared secret key can comprise any of a pre-shared secret key 129a, a derived shared secret key 129b, or a symmetric key 127 (where a module 101 and a server 105 both share the key). In addition, and as described in a step 703 in FIG. 7, in an exemplary embodiment a shared secret key 129 can comprise the combination of an initial module private key 112b and an initial module public key 111b, and the use of the two initial keys can comprises a shared secret key 129 for a sub-step 703 in an optional step 711 in FIG. 10. Also as described in FIG. 7, a sub-step 703 could take place concurrently with a sub-step 702 or possibly concurrently with a sub-step 701, such as during manufacturing or before a module 101 leaves a manufacturing facility.
After a sub-step 703 in an optional step 711 in FIG. 10, the next sub-step can comprise a sub-step 704 as depicted and described in FIG. 7. In this sub-step 704, a module 101 can conduct a 2-way authentication with a set of servers 105 using the shared secret key 129. Upon mutual authentication, a module 101 can record a second set of cryptographic parameters 126. The second set of cryptographic parameters 126 could comprise a subset of cryptographic parameters 126a as illustrated in FIG. 1e. Or, the second set of cryptographic parameters 126 could be equal to the first set of cryptographic parameters 126 from a sub-step 703. The details for a module 101 to perform a mutual authentication using shared secret key 129 and receiving a second set of cryptographic parameters 126 are depicted and described in connection with step 704 in FIG. 7. In this manner, by using an optional step 711 before a step 1001, module 101 and a server 105 can be mutually authenticated before a step 1001. The use of a step 711 could be optionally omitted, and subsequent steps in FIG. 10 could be used by a module 101 and a set of servers 1010 without a previous step 711.
At a step 1001 of FIG. 10, a module 101 can send a first message 208, where the first message 208 can include a module identity 110 and a first public key identity 111a. As received by a server 105 within a set of servers 1010, the first message 208 in a step 1001 could include a first source IP:port number equal to IP address 210 and source port number 605. As sent by module 101, the first message 208 in a step 1001 could include a first source IP:port number equal to IP:port number 204. Although firewall 104 is illustrated in FIG. 10 as operating as a “NAT Firewall”, a firewall 104 in a system 1000 could also operate as a symmetric firewall without NAT functionality and in this case the first message 208 in a step 1001 as received by a set of servers 1010 could include a source IP:port number equal to IP:port 204. In an exemplary embodiment, within a system 1000 where a module 101 optionally used a step 711 before a step 1001, many messages could have previously flowed between module 101 and a set of servers 1010 before the first message 208 in a step 1001.
At a step 1002, a set of servers 1010 can use the module identity 110 and/or module public key identity 111a in order to query other servers such as a server associated with a certificate authority 118, a module provider 109, or an eUICC subscription manager 164 in order to receive a first module public key 111 or certificate 122 for the module identity 110 and/or module public key identity 111a. Note than in an exemplary preferred embodiment, module 101 may use a plurality of module public keys 111 and/or certificates within a relatively short period of time (such as, but not limited to, using more than one module public key 111 within the same month). Different exemplary multiple module public keys 111 used concurrently by a module 101 are described elsewhere herein. In this embodiment where module 101 uses multiple module public keys 111 and/or certificates 122 in a relatively short period of time, the module public key identity 111a can serve as a useful index or pointer to a particular module public key 111 that a module 101 prefers to utilize with a set of servers 1010.
In an exemplary embodiment for a step 1002, a module 101 could also optionally send the relevant module public key 111 in a step 1001, but a step 1002 may be conducted by a set of servers 1010 in order to verify, query, or obtain the module public key 111 and/or certificate 122 from other servers. For example, if a module 101 had not previously conducted the optional step 711 in a FIG. 10, and no authoritative information is available about a module 101 to a set of servers 1010 (such as not having a shared secret key 129 available in the case where a step 711 was omitted), then a set of servers 1010 may preferably use the information in a message 208 received in a step 1001 to query the other servers illustrated in FIG. 10 (i.e. servers for 118, 109, or 164) in a step 1002 in order to obtain verification of the module identity 110 and/or a module public key 111 received in a step 1001, including obtaining a certificate 122. In other words, for embodiments where steps within a step 711 are omitted, module 101 could sent a message 208 with a module identity 110 or module public key identity 111a in a step 1001, and in a step 1002 a set of servers 1010 could check with other servers to obtain a module public key 111 from other servers illustrated.
In an embodiment where module 101 sends the module public key 111 in a step 1001, the module 101 preferably includes the module identity 111a. Module 101 could also send a certificate 122 in a step 1001, but the set of servers 1010 can independently query other servers for the certificate 122 or module public key 111 (query using the module identity 110 or module public key identity 111a from a step 1001). The query to other servers can be used to independently and separately receive the module public key 111, in order for a set of servers 1010 verify or compare that a received module public key 111, which could comprise an initial module public key 111b loaded by a manufacturer, matches the module public key 111, possibly in the form of a certificate 122, received from an independent and authoritative third party.
In an exemplary embodiment for a step 1002, a set of servers 1010 can also query other servers such as a certificate authority 118, a M2M service provider 108, an eUICC subscription manager 164, and/or a shared module database 105k in order to receive a first set of cryptographic parameters 126. A set of cryptographic parameters 126 is depicted and described in connection with FIG. 1 d, FIG. 1e, and FIG. 7, and elsewhere herein. The first set of cryptographic parameters 126 in a step 1002 could comprise the parameters 126a within a certificate 122 illustrated in a FIG. 1f. Within a step 1002 a set of servers 1010 could receive a certificate 122 for a module 101 with the module identity 110 from another server illustrated, where the certificate 122 could include (i) the module public key 111, (ii) the module identity 110, (iii) a module public key identity 111a, and (iv) a signature 123 from a certificate authority 118. Within a step 1002, a set of servers 1010 could also verify a chain of signatures 123 within a certificate 122 for a module 101. A set of servers 1010 could use a different IP:port number than IP:port 207 to query external servers for information pertaining to a first module public key 111 and a first set of cryptographic parameters 126.
After a step 1002, at a step 1003 a set of servers 1010 could send a module 101 a response 209. In an exemplary embodiment, the response 209 can include a server digital signature 506, where module 101 can verify the server digital signature 506 using the server public key 114. As contemplated herein, a server public key 114 can also comprise a network public key 502, although these two keys could be different, where a server public key 114 could be associated with a particular server 105 or set of servers 1010, and a network public key 502 could be associated with an M2M service provider 108. By receiving a server public key 114 in a step 1003, module 101 can authenticate the server identity 206 and verify or confirm that the module 101 is communicating with a correct server 105 (such as not receiving data from an imposter or a “man in the middle” attack). The server 105 preferably sends the response 209 to the source IP:port received in the first message 208 in step 1001. Server digital signature 506 could be optionally omitted in a step 1003 in embodiments where module 101 performs a step 711 before a step 1001, as illustrated in FIG. 10.
At a step 1004, a symmetric key 127 could be shared between the set of servers 1010 and the module 101. The symmetric key 127 could be shared in one of two manners: (A) by the mutual derivation of symmetric key 127 using a key derivation function 141f depicted and described in connection with FIG. 9b and FIG. 1 d, or (B) encrypting a symmetric key 127 using an asymmetric ciphering algorithm 141a and sending it to the other node. For option (B) to communicate or share a symmetric key 127 at step 1004, the symmetric key 127 could be sent either from (i) a set of servers 1010 or (ii) a module 101 using an asymmetric ciphering algorithm 141a and either (i) the module public key 111 from a step 1002 or (ii) the server public key 114, respectively. Values for using an asymmetric ciphering algorithm 141a could be specified from the first set of cryptographic parameters 126 at either a step 1002 or a step 1001. The set of servers 1010 could record the symmetric key 127 from a step 1004 in a shared module database 105k, such that different servers 105 within a set of servers 1010 could use the symmetric key 127 in communication with the module 101. An exemplary datagram 601a that includes a symmetric key 127 within an encrypted data that uses asymmetric ciphering 141a is illustrated in element 701a of FIG. 7 of U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety. For option A to communicate or share symmetric key 127 at step 1004, the module 101 or set of servers 1010 can send a key exchange token 906 to the other node in order to mutually derive the symmetric key 127 using a key derivation function 141f. In an exemplary embodiment, the module 101 can receive the key exchange token 906 an use a module key exchange algorithm 905 to derive a symmetric key 127 in a step 1004.
At a step 1005, a set of servers 1010 could record that the use of a second set of cryptographic parameters 126 for a module 101 may be preferred. A step 1005 could take place earlier in the sequence of message flow illustrated in FIG. 10, such as even before a step 1001. An example of the case in the previous sentence could be where a set of servers 1010 needs to initially communicate with a module 101 using a “base” set of cryptographic parameters 126 with an initial module public key 111b, and after initial secure communication is established, then the set of servers 1010 could use a different set of cryptographic parameters 126 and request that the module 101 derive a new set of module PKI keys using the different set of cryptographic parameters 126. In another embodiment, a relatively long period of time such as several years could transpire between a step 1004 and a step 1005 (with many additional messages not shown in a FIG. 10 communicated between a module 101 and a server 105 in the time between a step 1004 and a step 1005). Over time and for various commercial and security needs, a preferred set of cryptographic parameters 126 can change, such as the use of longer key lengths, or adoption of new asymmetric ciphering algorithms 141a, including the use of new ECC curves. Consequently, in a step 1005, a set of servers 1010 could record a second set of cryptographic parameters 126.
At a step 607 in FIG. 10, a module 101 could receive the second set of cryptographic parameters 126 from the set of servers 1010. Although not depicted in FIG. 10, a module 101 preferably sends a message 208 with the module identity 110 to the set of servers 1010 after a step 1004 and before a step 607, with the result that firewall 104 ports will be temporarily opened and bound so that a server 105 in a set of servers 1010 can send a response 209 back to the module 101. A step 607 with a response 209 is also depicted and described in connection with FIG. 6 and FIG. 7. The terminology depicted for a response 209 at a step 607 of “209:504: . . . ” can refer from left to right as the structure for an exemplary response 209 illustrated in FIG. 6, where the response 209 can include server encrypted data 504, and the server encrypted data can include a second set of cryptographic parameters 126. Although not depicted in FIG. 10, the second set of cryptographic parameters 126 could be included in a profile for an eUICC 163. The second set of cryptographic parameters 126 in a response 209 can be included in a server encrypted data 504. In this manner, the second set of cryptographic parameters 126 can remain confidential and reasonably securely received by a module 101.
Note that the symmetric key 127, or session key, used to cipher the second set of cryptographic parameters 126 in a step 607 in FIG. 10 could be communicated in a step 1004 above or a similar step using an asymmetric ciphering algorithm 141a or a key derivation function 141f. In an exemplary embodiment, the second set of cryptographic parameters 126 in a step 607 in FIG. 10 may not be encrypted and can also be sent as plaintext within a response 209. In addition, the set of cryptographic parameters 126 in a step 607 in FIG. 10 may be communicated in the form of a reference to a set of cryptographic parameters 126 from the use of a set of cryptographic parameters token 126c (and thus a name or identity of the set of parameters 126 could be communicated instead of the full set of cryptographic parameters 126). As contemplated herein, for any reference to a set of cryptographic parameters 126 in FIG. 5b through FIG. 10, the use of a set of cryptographic parameters token 126c can be substituted for communicating a complete list of cryptographic parameters 126.
For embodiments where a module 101 uses an eUICC 163, a step 607 illustrated in FIG. 10 could comprise module 101 receiving a profile 163a, which could also contain the second set of cryptographic parameters 126. The received eUICC profile 163a could be included in a server encrypted data 504, and the server encrypted data 504 could be ciphered using a symmetric key 127 communicated in a step 1004. Or, the server encrypted data 504 for a step 607 could be ciphered with a different symmetric key 127. The set of servers 1010 could obtain the received module profile 163b from an eUICC subscription manager 164. Note that a response 209 which includes a received eUICC profile 163a in a step 607 in FIG. 10 can utilize a source IP:port number 207 that is different than a source IP:port number 207 in a response 209 in a step 1003 above. In other words, as contemplated herein, the numeric value for an IP:port number 207 can change over time, but a pair of datagrams comprising a message 208 and an resulting response 209 can utilize the same numeric value for an IP:port number 207.
At step 1006, a module 101 can send a subset of cryptographic parameters 126a, where the subset of cryptographic parameters 126a can be a subset of the cryptographic parameters 126 received in a step 607. FIG. 1e above illustrates an exemplary “handshake” or “negotiation” of a set of cryptographic parameters 126 between a server 105 and a module 101, and the data illustrated in FIG. 1e can apply to step 607 and step 1006 in FIG. 10. Alternatively, the subset of cryptographic parameters 126a could be omitted, and the set of cryptographic parameters 126 received by a module 101 in a step 607 could be specific enough that module 101 does not need to select any options within the set of cryptographic parameters 126. In this case (where a step 1006 is optionally omitted), then a set of cryptographic parameters 126 in a step 607 could also comprise a subset of cryptographic parameters 126a. In addition, the terminology depicted for a message 208 at a step 1006 of “208:110:403:with Subset 2nd Parameters 126a” can refer from left to right as the structure for an exemplary message 208 illustrated in FIG. 6, with a message 208 containing a module identity 110 and a module encrypted data 403, where “Subset 2nd Parameters 126a” would be inside the module encrypted data 403.
Other data such as, but not limited to, source and destination IP:ports, a datagram packet header, and a checksum 603, plus optional channel coding 406 could be included in a packet comprising a message 208 sent by module 101 at a step 1006 and other messages 208 illustrated in FIG. 10. In an exemplary embodiment, the second subset of cryptographic parameters 126a in a step 1006 in FIG. 10 may not be encrypted and can also be sent as plaintext within a message 208. In general, where the use of encrypted data in the form of a module encrypted data 403 or server encrypted data 504 is illustrated in various Figures, including FIG. 10, the present invention contemplates that encryption may also be optionally omitted at the network layer and application layer and the data can be communicated as plaintext in these layers (but encryption could be performed at the data-link layer, such as ciphering data over a public wireless network 102). In an exemplary embodiment, module 101 can also use forward error correction at a step 1006, or other steps illustrated in FIG. 10 and related Figures where a module 101 sends data, such that a module 101 can send multiple copies of the same or equivalent datagram comprising a message 208 in order to increase the probability that a server 105 or set of servers 1010 receives at least one datagram comprising a message 208.
At a step 709 in FIG. 10, a module 101 can derive a new module public key 111 and a new module private key 112 using the parameters 126 negotiated or communicated between steps 607 and 1006. A step 709 in FIG. 10 can include the use of an eUICC 163 for module 101, and a step 709 for FIG. 10 can include embodiments that do not depend on the presence of an eUICC 163. The use of a step 709 is depicted and described in connection with FIG. 7 above. Although the text for a step 709 is depicted in FIG. 7 as “Module Derives 2nd Public Key 111 and 2nd Private Key 112 Pair, using 3rd Parameters 126”, in the context of FIG. 10, the second key pair would be derived using the second set of parameters 126 negotiated between steps 607 and 1006. In other words, the set of cryptographic parameters 126 used for a step 709 either in FIG. 7 or FIG. 10 can comprise the most recent set of cryptographic parameters communicated between a module 101 and a server 105 (i.e. the second set of cryptographic parameters 126 in FIG. 10 or the third set of cryptographic parameters in FIG. 7). The module 101 PKI key pair resulting from a step 709 could comprise either a module PKI key pair that uses either ECC algorithms 154 or RSA algorithm 153. The key lengths and other parameters for a module 101 to process the module 101 PKI key pairs can be specified in the set of cryptographic parameters 126 negotiated or communicated between steps 607 and 1006.
At a step 709 in FIG. 10, the module 101 could use a set of key pair generation algorithms 141e in a set of cryptographic algorithms 141a in order to derive a second module private key 112 and a corresponding second module public key 111. The first module public key 111 can be previously used in a step 1002 and the first module private key 112 can be previously used in a step 1004, although these first module 101 PKI keys could also be used in communication that is not shown (i) after a step 1004 within FIG. 10 (such as the case where an extended period of time such as years transpired between step 1004 and step 709 in FIG. 10), and (ii) before a step 709 in FIG. 10. A module 101 could determine that new module 101 PKI keys are preferred or desirable for many reasons before or upon a step 709, including the receipt of new cryptographic parameters 126 in a step 607, the transfer of ownership or control of module 101, the opening of an enclosure for a module 101 where the first module private key 112 could be compromised, the receipt of a module instruction 502 of “derive new keys” (illustrated in response 209 in FIG. 6), and other reasons exist as well.
At a step 710 within FIG. 10, the module 101 can send a message 208 that includes the second module public key 111 derived at a step 709. The terminology depicted for a message 208 at a step 710 of “208:110:403:2nd 111a:2nd 111” can refer from left to right as the structure for an exemplary message 208 illustrated in FIG. 6, with a message 208 containing a module identity 110 and a module encrypted data 403, where the second module public key identity 111a and second module public key 111 could be inside the module encrypted data 403. In exemplary embodiments, the module public key identity 111a could optionally be omitted in a step 710 and the data within a message 208 could also optionally be sent as plaintext. In the embodiment where module 101 sends a message 208 with the derived module public key 111 at a step 710 and also encrypts the module public key 111 in a module encrypted data 403, the symmetric key 127 used with a symmetric ciphering algorithm 141b could be communicated between module 101 and a set of servers 1010 in a prior communication, such as, but not limited to, the transfers of a symmetric key 127 in a step 1004. Also, although a single instance of the transfer of a symmetric key 127 in a step 1004 is illustrated in FIG. 10, over time multiple different symmetric keys 127 could be communicated between a module 101 and a set of servers 1010 using a step 1004 or similar secure transfer, before module 101 sends the derived, second module public key 111 in a step 710. In an exemplary embodiment, module 101 could use the most recent symmetric key 127 communicated between module 101 and a set of servers 1010 in order to send a module encrypted data 403 with the derived, second module public key 111 at a step 710 in FIG. 10.
In an exemplary embodiment, the derived, second module public key 111 in a step 709 of FIG. 10 could be sent outside the module encrypted data 403 (such as plaintext) in a message 208 at a step 710, but module encrypted data 403 could be used with the message 208 for either (i) sending other potentially sensitive data along with the module public key 111, such as, but not limited to, cryptographic parameters 126, or (ii) sending encrypted data using a symmetric key 127 such that a server 105 or set of servers 1010 could verify that module 101 has access to the symmetric key 127. Thus, the module encrypted data 403 in a message 208 at a step 710 could be used to authenticate or verify that the module public key 111 received in a message 208 properly belongs to a module 101 with a module identity 110. In other words, the proper processing of a module encrypted data 403 using a symmetric key 127 in a message 208 at step 710 can prevent imposters or the fraudulent submission of a module public key 111 in a step 710.
Note that a step 710 as depicted and described in connection with FIG. 7 includes the authentication of the derived, second module public key 111, and a step 710 in FIG. 10 can also include the steps for a module 101 to authoritatively send the derived, second module public key 111. For the embodiment where a server 105 uses a first module public key 111 (possibly from a step 1002) to authenticate a derived, second module public key 111 from a step 710, a server 105 that did not previously have or record the first module public key 111 could use the module identity 110 query other servers such as, but not limited to, a shared module database 105k, a certificate authority 118, or a M2M service provider 108 in order to obtain the first module public key 111 to authenticate or verify the derived, second module public key 112 received in a step 710.
The module identity 110 in a message 208 at a step 710 could be sent as an encrypted module identity 110a, such that the module identity 110 is ciphered or obfuscated. A module 101 could a symmetric ciphering algorithm 141b in order to send the module identity 110 as an encrypted module identity 110a. For and embodiment where module 101 sends module identity 110 as an encrypted module identity 110a where the encrypted module identity 110a is ciphered using a symmetric ciphering algorithm 141b, a key such as a symmetric key 127 to encrypt the module identity 110 into an encrypted module identity 110a could be communicated at a prior step such as, but not limited to, a step 1004. In general, the present invention contemplates that an encrypted module identity 110a can be used in place of a module identity 110 in Figures where a module 101 is depicted and described as sending a module identity 110.
The message 208 in a step 710 in FIG. 10, as received by a server 105 can include a second source IP:port 210:605 that is different than the first source IP:port in a message 208 at a step 1001. The source IP:port 210:605 could change reasons including, but not limited to, (i) firewall 104 operating as a NAT firewall changes port bindings over time, (ii) the packets from module 101 to a set of servers 1010 route through different firewalls 104 over time, such as module 101 connecting to different networks 102 over time and a first network 102 is used by module 101 in a step 1001 and a second network 102 is used by a module 101 in a step 710, and (iii) a module 101 could use a different source IP:port number 204 for a step 1001 and a step 710. The present invention contemplates that module 101 can use a different source IP:port for sending the various messages 208 depicted and described in various Figures throughout the present invention (an correspondingly use the different IP:port numbers to receive various responses 209 to the message 208). The IP address 202 for a module 101 to use in an IP:port number 204 can change over time (illustrated in FIG. 2), such as if a module 101 uses different networks 102 for sending messages 208 over time.
Although a message 208 at a step 710 in a FIG. 10 depicts a module 101 sending the message 208 at a step 710 to a server 105 within a set of servers 1010, a module 101 can send the message 208 at a step 710 to a different server than the server 105 illustrated in FIG. 10. In other words, according to exemplary embodiments, a module 101 can send any of the messages 208 depicted in various Figures to different servers 105 over time, and the different servers 105 could communicate with other servers 105 such that the multiple servers 105 operate in a coordinated manner using a network, and the multiple servers 105 could function as a set of servers 1010. As one example, the first message 208 in a step 1001 could be sent to a first server 105, and the message 208 in a step 710 could be sent to a second server 105. The use of different servers 105 for a module 101 to send a message 208 could be identified by the use of a different destination IP address within the message 208. Other possibilities exist as well for the use of multiple servers 105 in a set of servers 1010 without departing from the scope of the present invention.
At a step 1007, after completing of a step 710 in FIG. 10, a server 105 or set of servers 1010 can record the new, authenticated second module public key 111 with other servers illustrated. The data recorded by a server 105 could include the module identity 110, a module public key identity 111a, and a second module public key 111, plus an additional, optional subset of cryptographic parameters 126a. The data recorded by a server 105 in a step 1007 could be in the form of a certificate 122. In this manner, the second module public key 111, possibly in the form of a certificate 122, can be made available to other servers 105 within a set of servers 1010 over time, and the other servers 105 could also use the subset of cryptographic parameters 126a and the second module public key 111 from a step 709 in order to securely communicate with a module 101. The use of a step 1007 could also result in the second module public key 111 (with associated data such as a certificate 122, module identity 110, module public key identity 111a, and a subset of cryptographic parameters 126a for the second module public key 111) being made available to other servers outside of the set of servers 1010, such as a server 105 belonging to a different M2M service provider 108 than a M2M service provider 108 operating the set of servers 1010. Note that a step 1007 could be optionally omitted, and a set of servers 1010 could record the second module public key 111 internally, and the second module public key 111 could also be kept confidential and not shared with other servers, thereby further increasing the security of a system 1000 and other systems illustrated herein.
At a step 1008, after sending a message 208 (which could comprise the message 208 in step 710 in FIG. 10, or could comprise a different message 208 after a step 710 where the different message 208 after a step 710 is not illustrated in FIG. 10), module 101 could receive a response 209 that includes either (A) a second symmetric key 127 that is ciphered using an asymmetric ciphering algorithm 141a or (B) a key exchange token 906. The response 209 in a step 1008 could include a server encrypted data 504. For case (A) where a symmetric key 127 is received by module 101 in a step 1008, the server encrypted data 504 in a response 209 for a step 1008 that includes a second symmetric key 127 could be ciphered using (i) the derived, authenticated, second module public key 111 sent by module 101 in a step 710 and (ii) an asymmetric ciphering algorithm 141a. At a step 1008 the module 101 can decipher the server encrypted data 504 containing the second symmetric key 127 using the derived, second module private key 112 and an asymmetric ciphering algorithm 141a. A module 101 can use the second subset of cryptographic parameters 126a from a step 1006 with an asymmetric ciphering algorithm 141a in order to (i) decrypt the server encrypted data 504 received in a step 1008, and (ii) read the plaintext second symmetric key 127. An exemplary datagram 601a that includes a symmetric key 127 within an encrypted data that uses asymmetric ciphering 141a is illustrated in element 701a of FIG. 7 of U.S. patent application Ser. No. 14/039,401, filed Sep. 27, 2013 in the name of John Nix, which is hereby incorporated by reference in its entirety. Note that in a step 1008, although the set of servers 105 are illustrated as sending the second symmetric key 127 in a response 209, the module 101 could alternatively send the second symmetric key 127 in a message 208, where the second symmetric key 127 could be within a module encrypted data 403 that is ciphered with an asymmetric ciphering algorithm 141a and the server public key 114 and also uses the second subset of cryptographic parameters 126 from a step 1006.
In another embodiment for case (B) in the above paragraph where module 101 and a set of servers 1010 use a key derivation function 141f in a step 1008, a module 101 and a set of servers 1010 could conduct a key exchange such as Diffie Hellman, ANSI-X.9.63 160, or ECDH 159 in a step 1008 instead of transmitting and/or receiving the full second symmetric key 127. The key exchange could involve sending numbers or values, possibly including a random number 128a for a key exchange token 906, instead of the actual symmetric key 127. As illustrated in FIG. 9b, a key derivation function 141f could be used with the numbers or values sent for a key exchange token 906 to derive a shared symmetric key 127. As contemplated herein, in Figures such as FIG. 10 where a symmetric key 127 is illustrated as communicated between two nodes, instead of a symmetric key 127 being directly communicated, values for a key derivation function 141f such as a key exchange token 906 could communicated as a proxy for the symmetric keys 127 illustrated, and the nodes can use the key exchange token 906 with a key derivation function 141f as illustrated in FIG. 9b to mutually derive a symmetric key 127. In other words, in various figures illustrated herein, where a symmetric key 127 is illustrated as communicated, values to determine a shared symmetric key 127, such as a key exchange token 906, could be communicated instead. The key exchange token 906 could be input into a key derivation function 141f (with a public key and a private key as illustrated in FIG. 9b) in order to output a derived symmetric key 127. As contemplated herein, the term “sending a symmetric key” can comprise either (i) sending the symmetric key 127 using an asymmetric ciphering algorithm 141a and PKI keys, or (ii) sending a key exchange token 906 for a key derivation function 141f such that a symmetric key 127 could be determined from the data sent for the key derivation function 141f. Also as contemplated herein, the term “receiving a symmetric key” can comprise either (i) receiving the symmetric key 127 using an asymmetric ciphering algorithm 141a and PKI keys, or (ii) receiving a key exchange token 906 for a key derivation function 141f such that a symmetric key 127 could be determined from the data sent for the key derivation function 141f. 
At a step 1009, a module 101 can send a message 208 that includes a module encrypted data 403, where the module encrypted data 403 is ciphered using the second symmetric key 127. The second symmetric key 127 (or a key exchange token 906 for a key derivation function 141f to determine the second symmetric key 127) could be sent or received in a prior step 1008. The module encrypted data 403 using the second symmetric key 127 could include a server instruction 414, sensor data 305, a timestamp 604, and a security token 401. Security token 401 and timestamp 604 can prevent replay attacks. If a timestamp 604 is included in a module encrypted data 403, then a security token 401 could optionally be omitted in a step 1009. The message 208 in a step 1009 could contain data for a message 208 as depicted and described in connection with FIG. 6. The module identity 110 could comprise an encrypted module identity 110a, although the module identity 110 could also be sent as plaintext or as a session identity such that the session identity (or temporary module identity 110) within a message 208 at a step 1009 can change over time but also be uniquely associated with a module identity 110 persistently associated with a module 101. The module encrypted data 403 in a message 208 could be ciphered with a symmetric ciphering algorithm 141b and the second symmetric key 127 from a step 1008.
CONCLUSION
Various exemplary embodiments have been described above. Those skilled in the art will understand, however, that changes and modifications may be made to those examples without departing from the scope of the claims.

## Claims

1. A method for a hardware module with a radio to use a derived public key infrastructure (PKI) key pair, the method performed by the hardware module, the method comprising:
reading a first module private key and an identity from a nonvolatile memory, and sending the identity;
receiving via the radio a first symmetric key, wherein the first symmetric key is decrypted using the first module private key;
receiving via the radio a set of cryptographic parameters, wherein at least a portion of the set of cryptographic parameters is decrypted using the first symmetric key;
selecting a subset of the set of cryptographic parameters, and sending the subset;
deriving a second module private key and a module public key using the subset, wherein the derived module public key is associated with a module public key identity;
transmitting via the radio the derived module public key and the module public key identity, wherein the hardware module authenticates using the first module private key;
using the second module private key and a key exchange token to derive a second symmetric key for a symmetric ciphering algorithm;
encrypting a sensor measurement with the second symmetric key; and,
using an IP:port number to (i) send a message with the encrypted sensor measurement and (ii) receive a response to the message sent.

2. The method of claim 1, wherein the identity comprises an initial module public key identity, and wherein the initial module public key identity is associated with an initial module public key, and wherein the first module private key and the initial module public key comprise a PKI key pair.

3. The method of claim 1, further comprising (i) reading a module identity from the nonvolatile memory, and (ii) transmitting via the radio the module identity with the module public key identity, wherein the hardware module is associated with a plurality of module public keys.

4. The method of claim 1, wherein authenticating using the first module private key further comprises one of (i) sending a module digital signature, wherein the module digital signature is processed using the first module private key, and (ii) encrypting with a third symmetric key for the symmetric ciphering algorithm, wherein the third symmetric key is transferred by at least one of (a) receiving the third symmetric key using an asymmetric ciphering algorithm and the first module private key, (b) deriving the third symmetric key using a key derivation function and the first module private key, and (c) sending the third symmetric key (x) using an asymmetric ciphering algorithm, and (y) with the module digital signature.

5. The method of claim 1, further comprising transmitting via the radio a detach message to a wireless network both (i) after sending the message, and (ii) before receiving a radio resource connection release from the wireless network.

6. The method of claim 1, further comprising (i) reading an initial set of cryptographic parameters from the nonvolatile memory, and (ii) decrypting the first symmetric key using the initial set of cryptographic parameters, wherein the initial set of cryptographic parameters specifies a first elliptic curve defining equation, and wherein the received set of cryptographic parameters specifies a second elliptic curve defining equation.

7. The method of claim 1, further comprising a server receiving the identity, wherein the server queries for a certificate using the identity, and wherein the server encrypts the first symmetric key using the certificate and an asymmetric ciphering algorithm.

8. The method of claim 1, further comprising using a base point G and a key derivation function to derive the second symmetric key, wherein the key derivation function comprises an Elliptic Curve Diffie Hellman (ECDH) key exchange.

9. The method of claim 1, wherein the set of cryptographic parameters includes a validity time for the second module private key, a digital signature algorithm, and a secure hash algorithm.

10. The method of claim 1, wherein the method is performed by a system including the hardware module with the radio, and wherein the system further comprises:
the nonvolatile memory;
a sensor for acquiring the sensor measurement; and
a processor for one or more of decrypting at least a portion of the set of cryptographic parameters, deriving the second module private key, deriving the module public key, deriving the second symmetric key, or encrypting the sensor measurement.

11. A method for a hardware module with a radio to encrypt a sensor measurement, the method performed by the hardware module, the method comprising:
deriving a first symmetric key using a key derivation function, wherein at least a first module private key and a server public key are input into the key derivation function;
receiving via the radio a set of cryptographic parameters, wherein at least a portion of the set of cryptographic parameters is decrypted using the first symmetric key;
deriving a second module private key and a module public key using the set of cryptographic parameters;
transmitting via the radio the module public key, wherein the hardware module authenticates using the first module private key;
deriving a second symmetric key using the key derivation function, wherein at least the second module private key and the server public key are input into the key derivation function; and,
transmitting via the radio a module encrypted data, wherein the module encrypted data includes the sensor measurement, and wherein the module encrypted data is ciphered using the second symmetric key.

12. The method of claim 11, wherein the hardware module inputs a key derivation token into the key derivation function, wherein the hardware module selects a subset of the set of cryptographic parameters, and wherein the hardware module derives the second module private key using the subset.

13. The method of claim 11, wherein authenticating using the first module private key further comprises at least one of (i) transmitting via the radio a module digital signature, wherein the module digital signature is processed using the first module private key, or (ii) sending an encrypted data, wherein the hardware module uses the first symmetric key to encrypt the data.

14. The method of claim 11, further comprising:
using a first base point to derive the first symmetric key; and,
using a second base point to derive the second symmetric key, wherein the key derivation function comprises an Elliptic Curve Diffie Hellman (ECDH) key exchange.

15. The method of claim 11, further comprising transmitting via the radio a module public key identity before receiving the set of cryptographic parameters, wherein the module public key identity is associated with an initial module public key, and wherein the initial module public key is associated with the first module private key.

16. The method of claim 11, further comprising (i) receiving via the radio a module instruction for deriving the second module private key, wherein the module instruction is encrypted in a server encrypted data, and (ii) decrypting the server encrypted data using the first symmetric key.

17. The method of claim 11, wherein the method is performed by a system including the hardware module with the radio, and wherein the system further comprises:
a sensor for acquiring the sensor measurement; and
a processor for one or more of:
deriving at least one of the first symmetric key, the second symmetric key, the second module private key, or the module public key;
decrypting at least a portion of the set of cryptographic parameters; or
encrypting the sensor measurement to generate at least a portion of the module encrypted data.