# Patent

## Title
Method and apparatus for MoCA network with protected set-up

## Abstract

Systems and methods are disclosed for securing a network, for admitting new nodes into an existing network, and/or for securely forming a new network. As a non-limiting example, an existing node may be triggered by a user, in response to which the existing node communicates with a network coordinator node. Thereafter, if a new node attempts to enter the network, and also for example has been triggered by a user, the network coordinator may determine, based at least in part on parameters within the new node and the network coordinator, whether the new node can enter the network.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS/INCORPORATION BY REFERENCE
This patent application makes reference to, claims priority to and claims benefit from the U.S. Provisional Patent Application Ser. No. 62/051,532, filed on Sep. 17, 2014, and titled “Method and Apparatus for MoCA Network with Protected Set-Up,” the entire contents of which are hereby incorporated herein by reference.


FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[Not Applicable]
SEQUENCE LISTING
[Not Applicable]
MICROFICHE/COPYRIGHT REFERENCE
[Not Applicable]
BACKGROUND
Various communication networks, such as for example MoCA networks, lack a method and/or apparatus for securely, reliably, and efficiently adding a new node to the network. Limitations and disadvantages of conventional methods and systems for handling the addition of a new node to a network, for example a MoCA network, will become apparent to one of skill in the art, through comparison of such approaches with some aspects of the present methods and systems set forth in the remainder of this disclosure with reference to the drawings.



BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 shows a block diagram of a premises having a MoCA network.
FIG. 2 shows an example block diagram of a network node, in accordance with various aspects of the present disclosure.
FIG. 3 shows example message exchange sequences, and functions and tasks performed by various nodes, in accordance with various aspects of the present disclosure.
FIG. 4 shows example message exchange sequences, and functions and tasks performed by various nodes, in accordance with various aspects of the present disclosure.
FIG. 5 shows example message exchange sequences, and functions and tasks performed by various nodes, in accordance with various aspects of the present disclosure.
FIG. 6 shows example message exchange sequences, and functions and tasks performed by various nodes, in accordance with various aspects of the present disclosure.
FIG. 7 shows example message exchange sequences, and functions and tasks performed by various nodes, in accordance with various aspects of the present disclosure.



SUMMARY
Various aspects of this disclosure provide systems and methods for securing a network, for admitting new nodes into an existing network, and/or securely forming a new network. As a non-limiting example, an existing node may be triggered by a user, in response to which the existing node communicates with a network coordinator node. Thereafter, if a new node attempts to enter the network, and also for example has been triggered by a user, the network coordinator may determine, based at least in part on parameters within the new node and the network coordinator, whether the new node can enter the network.
DETAILED DESCRIPTION OF VARIOUS ASPECTS OF THE DISCLOSURE
As utilized herein the terms “circuits” and “circuitry” refer to physical electronic components (i.e., hardware) and any software and/or firmware (“code”) that may configure the hardware, be executed by the hardware, and or otherwise be associated with the hardware. As used herein, for example, a particular processor and memory (e.g., a volatile or non-volatile memory device, a general computer-readable medium, etc.) may comprise a first “circuit” when executing a first one or more lines of code and may comprise a second “circuit” when executing a second one or more lines of code.
As utilized herein, circuitry is “operable” to perform a function whenever the circuitry comprises the necessary hardware and code (if any is necessary) to perform the function, regardless of whether performance of the function is disabled, or not enabled (e.g., by a user-configurable setting, factory setting or trim, etc.).
As utilized herein, “and/or” means any one or more of the items in the list joined by “and/or”. As an example, “x and/or y” means any element of the three-element set {(x), (y), (x, y)}. That is, “x and/or y” means “one or both of x and y.” As another example, “x, y, and/or z” means any element of the seven-element set {(x), (y), (z), (x, y), (x, z), (y, z), (x, y, z)}. That is, “x, y, and/or x” means “one or more of x, y, and z.” As utilized herein, the terms “e.g.,” and “for example” set off lists of one or more non-limiting examples, instances, or illustrations.
The terminology used herein is for the purpose of describing particular examples only and is not intended to be limiting of the disclosure. As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “includes,” “comprising,” “including,” “has,” “have,” “having,” and the like when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof
It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Thus, for example, a first element, a first component or a first section discussed below could be termed a second element, a second component or a second section without departing from the teachings of the present disclosure. Similarly, various spatial terms, such as “upper,” “lower,” “side,” and the like, may be used in distinguishing one element from another element in a relative manner. It should be understood, however, that components may be oriented in different manners, for example a semiconductor device may be turned sideways so that its “top” surface is facing horizontally and its “side” surface is facing vertically, without departing from the teachings of the present disclosure.
A premises (e.g., a home, office, campus, etc.) may comprise a communication network for the sharing of information between various devices within the premises. For example, entertainment content may be received through a wide area network (WAN) provided by an MSO (Multi-system Operator), such as a cable television operator or satellite content provider. Content provided to the premises may be distributed throughout the premises over entertainment premises-based network (e.g., a home entertainment network, general premises-based communication network, etc.). The premises-based network may, for example, comprise a local area network (LAN) in any of a variety of configurations, such as a mesh network. An example protocol for establishing a premises-based network, for example a home entertainment LAN, is defined by the well-known MoCA (Multi-media over Coax Alliance) network protocol that is in-use today.
FIG. 1 shows a block diagram of a premises 100 (e.g., a home, office, campus, etc.) having a MoCA network 101. The discussion here will generally provide examples in a MoCA network environment. It should be understood, however, that the scope of this disclosure is not limited to MoCA networks. In the example shown in FIG. 1, the MoCA network 101 receives content from an MSO at a MoCA Point of Entry (POE). The MoCA network 101 enables the content to be communicated to all of the MoCA nodes 104, 106 108, and 110 on the MoCA network 101. In the example shown in FIG. 1, the MoCA nodes 104, 106, 108, and 110 are coupled (e.g., communicatively coupled via any of a variety of types of communication links) to either a television or a computer. For example, the information that is present in the computer 112 can be formatted for and displayed on any of the televisions by sending Prioritized Quality of Service (PQoS) data streams from the computer 112 to one or more of the televisions 114, 116, and 118 via the associated MoCA nodes 104, 106, 108, and 110.
When setting up a premises-based network (e.g., a home entertainment network), network security may be a consideration. For example, in various scenarios, it may be beneficial to ensure that only those devices that are authorized to transmit and receive information over the network can do so. Network security may be accomplished in any of a variety of manners. For example, one way in which security may be maintained within a LAN is to ensure that only devices that have a network password can enter the network. Therefore, in order to gain access to the network, a device must generally gain access first to the password used to secure the network.
One example manner of allowing a new device, sometimes referred to as a New Node (NN) to enter a network is to require that a person who is installing the NN press a button on the NN and also on one of the nodes within the network to which the NN is attempting to gain access. This procedure ensures that only nodes that are being installed by someone who has physical access to at least one node of the network can gain access to the network. Accordingly, a person may press a button (or otherwise cause a trigger to occur, for example via a user interface device, remote control, etc.) within or on the NN. The person may then, for example, be required to walk over to one of the nodes of the network to which access is sought, and press a button (or otherwise cause a trigger to occur) within or on that node. When one of the nodes within the network recognizes that this procedure has been properly followed, one of the nodes of the network may then share the network password with the NN, thus allowing the NN to communicate with the other nodes of the network. Once the NN has the password, it can then gain admission to the network.
For various communication networks, for example MoCA networks and others, a secure manner in which new nodes are added to such networks has either not been established or has been established but is inadequate (e.g., inefficient, non-secure, etc.). Various aspects of the present disclosure thus provide systems and methods for securely adding new nodes to a network (e.g., a premises-based network).
In accordance with various aspects of the present disclosure, a NN can securely gain access to an existing network (e.g., a network for which at least two nodes have previously established communication with one another in accordance with a network protocol). In addition, various aspects of the present disclosure allow a NN to establish a new network with another node in a secure manner, which other nodes can then join, for example in accordance with various aspects of the present disclosure that provide for an NN to securely join an existing network.
In accordance with various aspects of the present disclosure, a NN may be powered on (or, for example, hard reset, etc.). The NN may then enter a listening phase during which the NN attempts to detect a beacon signal. The beacon signal may, for example, come from a network coordinator node of a previously established network. Also for example, the beacon may come from another node that has not been able to find another node with which to establish a network and is currently seeking a second node with which to form a new network (e.g., a beaconing node). If the NN is triggered by a user prior to detecting a beacon, the NN may, for example, set a PBState flag to “PUSHED” indicating that the NN was triggered. The NN may also start a timer or clock (e.g., a walking timer) and continue to search until either the timer expires, the NN detects a beacon, or the NN starts to send beacons while continuing to search (e.g., the listening phase ends). The walking timer is set to time out after the amount of time allotted to walk from one node to another (e.g., to trigger such node) has elapsed.
If the NN detects a beacon prior to the walking time elapsing, then the NN may check whether a PBState flag is set to PUSHED (e.g., indicating that a network set-up session is underway, for example a network protected set-up). A beacon may, for example, be sent by a network coordinator, access point, mesh member, or other type of network node. If the PBState flag is set to PUSHED, then the NN may, for example, send a message (e.g., a Pre-Admission Discovery Request message) to the node that sent the beacon. The NN may, for example, identify itself and send protected set-up parameters (e.g., MoCA Protected Set-up (MPS) Parameters in a MoCA network scenario) that indicate the privacy status set within the NN. The NN may then, for example, attempt (or wait) to receive a response to the sent message (e.g., wait to receive a Discovery Response message in response to a Discovery Request message). If the NN receives a response (e.g., a Discovery Response message), the response may, for example, comprise protected set-up parameters of the responding node (e.g., MPS Parameters of a MoCA responding node). The NN may then, for example, check the privacy status of the responding node based on the protected set-up parameters received from the responding node and determine whether the two nodes are compatible to continue the process. If compatible, then the NN may, for example, exchange password information with the responding node. A decision may, for example, be made as to whether a password is required to be shared by the NN and the responding node. If so, a further decision may, for example, be made by the NN as to whether the NN provides the password to the responding node or whether the responding node provides the password to the NN. Alternatively, if the NN and the responding node are not compatible, then the attempt to establish a network between the two nodes may fail. In some cases, however, the NN may be able to gain admission to the network without a password exchange.
If the NN fails to detect a beacon within a predetermined amount of time (e.g., a period of time longer then the walk time, for example as indicated by a variable MPSWALK_TIME), the NN may enter beacon phase. Upon entering the beacon phase, the NN may take on the role of a network coordinator (NC), which may also be referred to as a network controller, for example performing beaconing functionality and/or any other functionality associated with a network coordinator). Accordingly, during beacon phase, the NC (formerly the NN) may transmit beacon signals. If a receiving node is powered on, has been triggered, and detects the beacon signals transmitted by the NC, then the receiving node may transmit a message (e.g., a Pre-Admission Discovery Request message in a MoCA scenario). The NC may then send a response (e.g., a Discovery Response message in a MoCA scenario) that includes protected set-up parameters of the NC (e.g., MPS Parameters of the NC in a MoCA scenario) and thus indicates the privacy status of the NC. The NC may then decide whether the privacy status of the two nodes is compatible. If so, the NC may further determine whether an exchange of passwords is necessary and/or how such an exchange of passwords is to take place.
In accordance with various aspects of the present disclosure, when an Existing Node (EN) (e.g., a node that is currently a member of a network) is triggered, the EN may ignore the trigger if its management parameter (e.g., MPSEN in a MoCA scenario) is set to DISABLE, or for example if a state flag (e.g., a PBState flag in a MoCA scenario) is set, indicating that the EN was previously triggered less than a predetermined time ago. However, if triggered and the management parameter (e.g., MPSEN) of the EN is set to ENABLE and the state flag (e.g., PBState flag) is not set (or set to CLEAR), then the EN may send a request. In an example MoCA scenario, the request may, for example, be sent as an MPS Request Protocol Information Element (IE) within a Reservation Request (RR) to the Network Coordinator (NC) that controls the network of which the EN is a member.
In accordance with various aspects of the present disclosure, in an example MoCA scenario, an NC that receives a RR with a MPS request may check the status of the PBState flag. If the state of the PBState flag is CLEAR, then the PBState flag is set to PUSHED. In addition, a register called PBNode is loaded with a value that indicates the identity of the EN that sent the MPS request. A walk timer is then started within the NC. Then, in the next Media Access Plan (MAP), the NC includes a Network MPS Session Protocol IE indicating that the NC received the MPS request and identifying the node that sent the MPS request. If the walk timer times out before a Pre-Admission Discovery Request message is received (e.g., from a NN), the MPS session is aborted, the PBState flag is set to CLEAR, and the walk timer is reset. When either the timer expires or the admission of the new node is complete or fails, the NC sends a message indicating that the MPS session has ended.
In accordance with various aspects of the present disclosure, the password exchange may comprise an M1 Request, an M2 Response, an M2 Acknowledge, an M3 Response and an M3 Acknowledge. Also in accordance with various aspects of the present disclosure, the password exchange may comprise transmission of a Discovery Response message with an NC Public Key Network IE, a Network Password message, and an acknowledgement of each.
FIG. 2 shows an example block diagram of a network node 200, in accordance with various aspects of the present disclosure. The node 200 may, for example, share any or all characteristics with the MoCA nodes 104, 106, 108, and 110 shown in FIG. 1 and discussed herein. The node 200 comprises a processor 202, a memory 204 and a radio frequency (RF) front end 206. In the transmit path, the RF front end 206 receives information from the processor 202. The information is modulated on signals generated by the RF front end 206. The RF front end 206 transmits such signals over a medium 208, such as over coaxial cabling used to connect nodes of a MoCA network. In the receive path, the RF front end 206 also receives signals from the medium 208, demodulates the signals to retrieve the information communicated by such signals, and passes the received information to the processor 202 for processing. It should be understood that, while the example node 200 shown in FIG. 2 is described with respect to a node connected via coaxial cable, the node may be connected to the network over any medium, such as wireless connection, twisted pair, optical fiber or any other medium that can transport signals from node to node.
The processor 202 within the node 200 performs several tasks. The example node 200 is shown and described as having a single processor 202 that performs all of the disclosed tasks and functions of the node 200. Nonetheless, it should be understood that the disclosed tasks and functions of the node 200 can be performed by any combination of hardware, firmware and software. Furthermore, any software or firmware can be executed by one or a combination of several independent or coordinated processors. For example, in various example implementations, it may be more efficient to use processors dedicated to performing a particular task or group of tasks. Also for example, the processor 202 (or processors) may comprise any of a variety of processing circuits (e.g., general purpose processors, microcontrollers, application-specific integrated circuits, programmable state machine devices, analog and/or digital circuitry, etc.). Such architectural variations are understood. Accordingly, the details of such architectures are not provided herein for the sake of brevity and illustrative clarity.
As mentioned previously, various aspects of the present disclosure may herein be presented in the context of a MoCA network. It should be understood, however, that the scope of this disclosure is not limited to methods and apparatus of a MoCA network.
In accordance various aspects of the present disclosure, the node 200 may perform in one of at least three distinct roles, non-limiting examples of which are provided herein. Furthermore, the particular role taken on by the node 200 may depend upon the tasks the node 200 is performing and the environment in which the node 200 exists. In an example implementation, the node 200 is powered on (e.g., power is initially applied to the node to start the node 200 operating), the node 200 is subjected to a hard reset causing state information to be lost, etc. When initially powered on, the node 200 is unpaired. For example, the node 200 has no affiliation with any network. Also, in accordance with an example implementation, the node 200 may have a number of default settings that are relevant to the disclosed method and apparatus. For example, a privacy setting referred to as PRIVACYEN may be initially set to DISABLED. In addition, there may for example be a plurality of parameters that are associated with the MoCA Protected Set-up (MPS) function of the node 200. Four example parameters comprise:

    
    
        MPSEN: Initialized to ENABLED.
        MPSPRIVACY_RECEIVE: Initialized to ENABLED.
        MPSPRIVACY_DOWN: Initialized to DISABLED.
        MPSWALK_TIME: Initialized to 2 minutes.
    
    


Initially, the node 200 may operate in the role of New Node (NN). For example, when the node 200 is initially turned on, it may enter a “Listening Phase”. In the Listening Phase, the node 200 may, for example, attempt to detect (or listen for) a beacon signal. For example, the RF front end 206, under the control of the processor 202, may search for a beacon signal transmitted by another node that is operating on the medium 208 to which the node 200 is connected. If the node 200 does not detect a beacon within a predetermined amount of time, the node 200 may then enter a “Beacon Phase”. In the Beacon Phase, the node 200 may, for example, transmit beacons for a period of time and also listen to see whether another node operating on the medium has detected and responded to the transmitted beacons. The Listening Phase/Beacon Phase sequence may, for example, be repeated multiple times.
Once the node 200 joins a network (e.g., through a process illustrated by example herein), the node 200 operates in the role of Existing Node (EN). In accordance with the various aspects of the present disclosure, at least one node in each network generally assumes the role of Network Coordinator (NC). The NC may, for example, be responsible for scheduling most or all of the traffic on the network. Additional examples regarding the role of NC are provided herein. In accordance with various aspects of the present disclosure, the node 200 may operate in accordance with the MoCA standard.
FIG. 3 shows example message exchange sequences, and functions and tasks performed by various nodes (e.g., between nodes of a network and/or nodes to be part of a network), in accordance with various aspects of the present disclosure. For example, FIG. 3 provides an illustration of various functions and tasks performed by a node when operating in each of the three example roles (e.g., NN, EN and NC). Note that in FIG. 3, as an initial condition, a network has already been formed by an NC 302 and an EN 304. The diagram of FIG. 3 shows time flowing from the top of the diagram to the bottom, with horizontal arrows 310-330, arrows that are closer to the top of the diagram depicting communications that occur before communications depicted by arrows that are closer to the bottom of the diagram. Furthermore, the horizontal arrows indicate a communication in the direction of the arrow between nodes 302, 304, and 306.
The first event shown is a user pressing an MPS button 332 on the EN 304 with MPS enabled (e.g., the MPSEN parameter of the EN 304 is set to ENABLE). The user pressing the MPS button on the EN 304 results in the EN 304 sending an MPS Request Protocol Information Element (PIE) 310 within a Reservation Request (RR) message. In an example implementation, the RR conforms to reservation requests sent in accordance with the MoCA standard, but the scope of various aspects of this disclosure is not limited thereto. TABLE 1 shows an example format of the MPS Request PIE.







TABLE 1







MPS Request PIE Format









Field
Length
Explanation





FRAME_SUBTYPE
4 bits
0x6 - MoCA 2 Operation


FRAME_TYPE
4 bits
0x7 - Protocol IE


IE_LENGTH
6 bits
=0


RESERVED
2 bits
Type III







Protocol IE Payload









TYPE
4 bits
0xTBD - MPS Request from an EN


RESERVED
12 bits 
Type III









Note that “0x” indicates that the value that follows is in hexadecimal format. Accordingly, the value 0x6 is equal to 0110 in binary format; the value 0x7 is equal to 0111 in binary format, etc. TBD indicates that the value is yet to be determined (e.g., the field is not yet assigned to carry any particular value). Any value that is not already assigned may be assigned for use in the future. Furthermore, it should be understood that each of the fields can be assigned to any value that has not previously been assigned to another function.
In response to the MPS request PIE 310 in the RR message, the processor 202 within the NC 302 checks the status of the local parameter PBState. For the sake of brevity, throughout this disclosure it should be assumed that when functions are disclosed as being performed by a node, the processor 202 within the node, for example alone or in conjunction with other circuitry, is generally responsible for performing the function (e.g., data analysis function, decision function, data determining function, transmitting and/or receiving control function, etc.).
If the value of the local parameter PBState is CLEAR, the NC 302 updates the value of the local parameter PBState to PUSHED. In addition, the NC 302 sets the local parameter PBNode to the Node ID of the EN 304 that sent the MPS Request PIE 310. In an example implementation, the Node ID of the EN 304 is included in the RR message sent by the EN 304. The NC 302 may also start a timer (e.g., an MPS walk timer). In an example implementation, in the next MAP message to be transmitted by the NC 302, the NC 302 includes a Network MPS Session Protocol IE 312 with the parameter CODE set to 0x0 and the parameter REQUESTING_NODE_ID set to the value of the parameter PBNode. TABLE 2 shows an example format of the MPS Response PIE 312 (e.g., the Network MPS Session PIE).







TABLE 2







Network MPS Session PIE format









Field
Length
Explanation





FRAME_SUBTYPE
4 bits
0x6 - MoCA 2 Operation


FRAME_TYPE
4 bits
0x7 - Protocol IE


IE_LENGTH
6 bits
=0


RESERVED
2 bits
Type III







Protocol IE Payload









TYPE
4 bits
0xTBD - Network MPS Session


CODE
4 bits
0x0 - Network MPS session start.




0x1 - Network MPS session stop.




Other values reserved.


REQUESTING_NODE_ID
8 bits
The ID of the Node that the response is




responding to









Alternatively, if the value of the parameter PBNode is PUSHED, then the NC 302 checks whether the value of the parameter PBNode is equal to the value of the Node ID of the EN 304 that sent the MPS Request PIE 310. If so, then the NC 302 had previously received an MPS request from this EN 302. Accordingly, the NC 302 may ignore the received MPS request. However, in an example implementation, if the value of PBNode is different from the Node ID of the EN 304 that sent the MPS Request PIE 310, then the NC 302 may reset the walk timer and set the value of the parameter PBState to CLEAR. Accordingly, if a user triggers more than one EN, the second EN trigger may cause the MPS session to end. A new session might then, for example, only occur if the user activates a third trigger. The NC may, for example, end the session by sending a PIE with CODE equal to 0x1 in the next MAP message after the second trigger from the different EN.
Similarly, if the walk timer expires (runs for longer than the allotted time) before the NC 302 receives a Pre-Admission Discovery Request message from an NN 306, then the NC 302 may set the parameter PBState to CLEAR and reset the walk timer. In addition, the NC 302 may send an MPS Session Protocol IE having the field CODE set to 0x1 in the next MAP message.
If the user triggers the NN 306 and the local management parameter MPSEN of the NN is ENABLED 334, the NN 306 may send a Pre-Admission Discovery Request message comprising an MPS Request Network IE 314. TABLE 3 shows an example format of the MPS Request Network IE 314.







TABLE 3







MPS Request Network IE Format









Field
Length
Value










IE Header









TYPE
8 bits
0x08- MPS Request Network IE


LENGTH
8 bits
0x02







IE Payload









RESERVED
12 bits 
Type III


MPS_PARAMETERS
4 bits
Bit 3 - Reserved




Bit 2 - Privacy. reflects the value of




ActivePrivacyEN




0b0 = Disabled




0b1 = Enabled




Bit 1 - Receive Privacy. If PairedState = un-




Paired: reflects the value of the Node's




MPSPRIVACY—RECEIVE




0b0 = Disabled




0b1 = Enabled




Is set to 0b0 if the PairedState = Paired.




Bit 0 = Downgrade Privacy. If Bit 1 is set to




0b1: reflects the value of the Node's




MPSPRIVACY— DOWN




0b0 = Disabled




0b1 = Enabled




Reserved Type III when Bit 1 = 0b0.


GUID
64 bits 
64 bit MAC address of the device









In response to the Discovery Request message comprising the MPS Request Network IE 314, the NC 302 may schedule an Admission Control Frame (ACF) slot in the next beacon during which the NC 302 transmits a Pre-Admission Discovery Response message comprising an MPS Response Network IE 316 to the NN 302. TABLE 4 shows an example format of the MPS Response Network IE 316.







TABLE 4







MPS Response Network IE Format









Field
Length
Value










IE Header









TYPE
8 bits
0x09- MPS Response Network IE


LENGTH
8 bits
0x02







IE Payload









NODE_ID
8 bits
The ID of the NC


CODE
4 bits
0x0 - MPS is disabled or not triggered.




0x1 - Network MPS is triggered.




Other values reserved.


MPS_ PARAMETERS
4 bits
When CODE = 0x1:




Bit 3 - Reserved




Bit 2 - Privacy




0b0 = Disabled




0b1 = Enabled




Bit 1 - Receive Privacy




0b0 = Disabled




0b1 = Enabled




Bit 0 = Downgrade Privacy




0b0 = Disabled




0b1 = Enabled




Reserved Type III when Bit 1 = 0b0.




Otherwise: Reserved Type III


REQUESTING_NODE_GUID
64 bits 
This field is copied from the MPS Request




Network IE that this response is responding to.









In this example, the NC 302 sets the CODE field to 0x1, since the PBState of the NC is PUSHED. It should be noted that the PBState was set to PUSHED in response to the NC 302 receiving the RR message from the EN 304 indicating that the EN 304 was triggered. Alternatively, the PBState may also be set to PUSHED if the NC is locally triggered. When the CODE field of the MPS Response Network IE 316 is set to 0x1 (e.g., when the NC 302 has either been triggered itself or has received an MPS request PIE indicating that an EN 304 has been triggered) the NC 302 may reset the walk timer. In addition, the status of various MPS Parameters may, for example, be provided by the NC 302 in the MPS Response Network IE 316 of the Discovery Response message. Three example MPS Parameters are (1) Privacy; (2) Receive Privacy; and (3) Downgrade Privacy. The values of these three example MPS Parameters within the NN 306 (transmitted to the NC 302 in the MPS Request Network IE 314 of the Discovery Request message), taken together with the values of the MPS Parameters within the NC 302, determine whether, and how, the nodes will exchange passwords. However, if the NC 302 is in a network, the Privacy parameter may indicate whether the network has privacy enabled or disabled. In this example case, Receive Privacy and Downgrade Privacy will be set to DISABLE.
These three example MPS parameters (e.g., Privacy) may, for example, indicate the privacy status of the node. It should be understood that when a node is operating as the NC of a network (e.g., there is at least one other EN in the network) and MPS is ENABLED, the node may be considered to be “PAIRED”. Accordingly, the node may maintain a parameter PairedState set to PAIRED. In an example implementation, when a node is PAIRED, privacy of the node is set to the privacy of the network. In addition, no change to the node privacy can occur. More generally, a Node may be considered PAIRED if it either formed or joined a network (completed admission) at any time since the last time its state was set to un-Paired. Once the parameter PairedState is set to PAIRED, the parameter may for example remain in this state until the management entity resets the nodes MPS using MPSRESET. If the management entity for a node resets PairedState to UNPAIRED, the node should update the parameter immediately, even if the node is currently in a network. The parameter should then remain in the UNPAIRED state until the node drops off the network.
The first of the three example parameters may, for example, indicate whether the node requires privacy. In an example implementation, if an NN 306 requires privacy, then the NN 306 can only join a network if the network has privacy enabled. However, the third example parameter (Downgrade Privacy), when enabled, may allow the NN 306 to enter a network for which privacy is disabled. For example, by allowing an NN to downgrade its privacy, the user can add the NN to the network without having to know the network password. Rather, the user may rely on the MPS procedure to ensure that the NN is entering a network of which the user approves.
The second of the three example parameters is Receive Privacy. When enabled, this parameter allows a node to receive the network password from another node. In addition, when enabled, the node state of the ActivePrivacyEN parameter can be changed during the MPS process. It should be understood that when a node is operating as the NC of a network (e.g., there is at least one other EN in the network), the password may be determined on a network wide basis. For example, in an example implementation, the NC 302 of a previously formed network cannot receive a password from another node. For example, once the password for a network has been established, it cannot be changed by an incoming NN. Accordingly, in an example implementation, the Receive Privacy parameter is always set to DISABLED when a node is admitted into a network (e.g., once the PairedStatus is set to PAIRED).
TABLE 5 provides an example MPS decision matrix that indicates the action to be taken by the network nodes 302, 304, 306, in accordance with various aspects of the present disclosure. These actions are based on the values of the MPS Parameters sent by the NC 302 in the MPS Response Network IE 316 of the Discovery Response message and the MPS Parameters sent by the NN 306 in the MPS Request Network IE 314 of the Discovery Request message.







TABLE 5







MPS Decision Matrix









MPS_PARAMETERS Sent by NC
MPS_PARAMETERS Sent by NN















Bit 1
Bit 0

Bit 1
Bit 0



Bit 2
(Receive
(Downgrade
Bit 2
(Receive
(Downgrade


(Privacy)
Privacy)
Privacy)
(Privacy)
Privacy)
Privacy)
Decision





DISABLED
N/A
N/A
DISABLED
N/A
N/A
Node








Privacy








Admission


DISABLED
DISABLED
N/A
ENABLED
DISABLED
N/A
FAILED


DISABLED
DISABLED
N/A
ENABLED
ENABLED
DISABLED
FAILED


DISABLED
DISABLED
N/A
ENABLED
ENABLED
ENABLED
NC: Node








Privacy








Admission,








NN: No








Privacy








Admission


N/A
ENABLED
N/A
ENABLED
DISABLED
N/A
NN to NC








PSWD








Exchange


DISABLED
ENABLED
N/A
ENABLED
N/A
N/A
NN to NC








PSWD








Exchange


ENABLED
DISABLED
N/A
DISABLED
DISABLED
N/A
FAILED


ENABLED
DISABLED
N/A
ENABLED
DISABLED
N/A
Node








Privacy








Admission


ENABLED
N/A
N/A
N/A
ENABLED
N/A
NC to NN








PSWD








Exchange


ENABLED
ENABLED
DISABLED
DISABLED
DISABLED
N/A
FAILED


ENABLED
ENABLED
ENABLED
DISABLED
DISABLED
N/A
NC: No








Privacy








Admission,








NN: Node








Privacy








Admission


ENABLED
ENABLED
ENABLED
ENABLED
DISABLED
N/A
NN to NC








PSWD








Exchange









There are six example decisions in the example MPS Decision Matrix of TABLE 5. The first example decision is that the NC sends a password to the NN (e.g., a password exchange from NC to NN). This occurs when, for example, the NC Privacy is ENABLED and the NN Receive Privacy is ENABLED. For example, when the NC has privacy enabled, it sends its password, and the NN can receive the password when NN Receive Privacy is ENABLED. In this case, none of the other MPS Parameters matter.
The second example decision is an NN to NC password exchange. In this case, Privacy in the NN 306 is ENABLED and Receive Privacy is ENABLED in the NC 302. Additionally, either the NN Receive Privacy is DISABLED or the NC Privacy is DISABLED. Alternatively, this may occur if all three parameters sent by the NC 302 are set to ENABLE, Privacy in the NN 306 is set to ENABLE and Privacy Receive in the NN is set to DISABLE. For example, in an example implementation, if an exchange from the NC to NN can occur, that exchange is favored over an NN to NC exchange. Therefore, if the NC Privacy is ENABLED and the NN Privacy Receive is ENABLED, the status of the NN Privacy and the NC Privacy Receive do not matter. In each other case in which the NN Privacy is ENABLED and the NC Privacy Receive is ENABLED, a password exchange from the NN to the NC will take place. It should be noted that, in an example implementation, the NC will only have Privacy Receive set to ENABLED when the NC is in beacon phase and the PairedStatus is set to UNPAIRED. Once the PairedStatus is set to PAIRED, the Privacy Receive state is set to DISABLED, since a paired node cannot change its password.
The third example decision is Node Privacy Admission. In this case, no password exchange occurs, but the admission process takes place using the NN's and NC's ActivePrivacyEN and ActivePSWD parameter settings. In one example case, both the NC 302 and the NN 306 have Privacy DISABLED. Therefore, there is no need to exchange security information. In an alternative example case, Privacy is ENABLED in both NC and the NN, but Receive Privacy is DISABLED in both, so no downgrade is possible. Nonetheless, since the Privacy in both the NC and NN agree, the admission process can go forward without a password exchange.
The fourth example decision is NC: No Privacy Admission/NN: Node Privacy Admission. In this case, Privacy is ENABLED in the NC, but the Downgrade Privacy parameter in the NC 302 is also ENABLED, allowing the NC to downgrade its privacy to operate with an NN that has Privacy DISABLED and Receive Privacy set to DISABLED. Therefore, the NC ActivePrivacyEN parameter is set to DISABLED, while the PRIVACYEN parameter remains ENABLED. It should be noted that each node has both an ActivePrivacyEN parameter and a PRIVACYEN parameter. The ActivePrivacyEN parameter can be changed through the MPS process if MPS Privacydown parameter is ENABLED. In addition, the ActivePrivacyEN parameter can change from DISABLED to ENABLED if Privacy Receive is set to ENABLED.
The fifth example decision is similar to the fourth example decision. In this case, NN: No Privacy Admission/NC: Node Privacy Admission. This occurs, for example, if the NN Privacy is ENABLED, the Downgrade Privacy parameter in the NN 306 is also ENABLED, the NN Receive Privacy is set to ENABLED, and the NC Privacy and Receive Privacy are set to DISABLED. Accordingly, the NN can downgrade and set the ActivePrivacyEN parameter to DISABLED, thereby allowing the admission process to go forward with an NC that has privacy set to DISABLED.
It should be noted that Node Privacy Admission does not require a downgrade in the state of the ActivePrivacyEN. In contrast, No Privacy Admission occurs when a downgrade to the privacy is necessary, thus setting the value of ActivePrivacyEN to DISABLED while the value of PRIVACYEN remains ENABLED.
The sixth example decision is FAILED. There are four example instances in the Matrix of TABLE 5 when the MPS admission process will fail. In the first example instance, both the Privacy and Receive Privacy parameters in the NC 302 are DISABLED. In addition, the Privacy Parameter in the NN is ENABLED and the status of Receive Privacy is set to DISABLED. Because the state of Receive Privacy in the NN is DISABLED, the NN cannot downgrade the Privacy. Therefore, it is not possible for the NN to complete the admission process.
In the second example instance, both the NC Privacy and Receive Privacy parameters are DISABLED. However, Privacy is set to ENABLED in the NN. The Receive Privacy in the NN is set to ENABLED, but downgrade is DISABLED in the NN. Therefore, the NN cannot complete the admission process.
In the third example instance, the MPS parameters sent by the NC have Privacy set to ENABLED and Receive Privacy set to DISABLED. The NN has Privacy set to DISABLED, and Receive Privacy set to DISABLED, therefore, the NN cannot complete the admission process. The Receive Privacy in the NN is set to DISABLED, therefore no downgrade is possible.
In the fourth example instance, the MPS parameters sent by the NC have Privacy set to ENABLED and Receive Privacy set to ENABLED, but Downgrade Privacy is set to DISABLED. The NN has Privacy set to DISABLED and Receive Privacy set to DISABLED. Therefore, as noted above, the NN cannot change its Privacy setting to enter the secure network.
Looking once again at FIG. 3, after sending the MPS Response Network IE 316 in the Discovery Response message, if the decision from TABLE 5 indicates that a password exchange is to take place, the NC 302 may, for example, schedule an ACF slot in the next beacon with the ACF_TYPE field set to 0x0F and the ADDITIONAL_ACF-TYPE field set to 0x20. The NC 302 may then wait to receive a Get Privacy Setting Request M1 message 318 from the NN 306 in the ACF slot. If, for any reason, the password exchange is not completed successfully, both the NC 302 and the NN 306 may set the PBState to CLEAR, and the NC 302 may send a Network MPS Session Protocol IE in a MAP with CODE set to 0x1 ending the MPS session. The NC 302 may then resume normal operation. The NN 306 should then, for example, continue searching for a network.
The format of an example Get Privacy Setting Request M1 message 318 is provided in TABLE 6.







TABLE 6







Get Privacy Setting Request M1 Message Format









Field
Length
Usage










MPDU Header









TRANSMIT_CLOCK
32 bits 
This value is the scheduled time derived from the




corresponding AU in the MAP.


PACKET_SUBTYPE
4 bits
0x7 - Get Privacy Setting Request M1


PACKET_TYPE
4 bits
0x9 - Link control II


VERSION
8 bits
0x10


RESERVED
8 bits


SOURCE_NODE_ID
8 bits
The NC node ID when sent by the NC. 0x00




otherwise.


RESERVED
8 bits


DESTINATION_NODE_ID
8 bits
0x00


PACKET_LENGTH
16 bits 
The total length of the MPDU frame body in bytes




(excluding the MPDU header).


MPDU_CONTROL_INFORMATION
32 bits 
This field is Type III reserved.


HEADER_FCS
16 bits 
MPDU header Frame Check Sequence - is




calculated over the MPDU header starting from the




Transmit_Clock field and ending with (including)




the MPDU_CONTROL_Information field. The




HEADER_FCS is calculated using CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1).







Frame Payload









DH_M1
1664 bits  
N1 || PKNN, where N1 and PKNN where PKNN




Diffie-Hellman Public Key of the NN and N1: a




128-bit secret random number (nonce) generated by




the NN


GUID
64 bits 
64 bit MAC address of the requesting node







Payload FCS









PAYLOAD_FCS
32 bits 
For all the Management and Control MPDUs, and




for the Ethernet data packet, the 32-bit FCS is




calculated using CRC-32-IEEE 802.3 (x{circumflex over ( )}32 + x{circumflex over ( )} 26 +




x{circumflex over ( )} 23 + x{circumflex over ( )}22 + x{circumflex over ( )}16 + x{circumflex over ( )}12 + x{circumflex over ( )}11 + x{circumflex over ( )}10 + x{circumflex over ( )}8 +




x{circumflex over ( )}7 + x{circumflex over ( )}5 + x{circumflex over ( )}4 + x{circumflex over ( )}2 + x + 1). For the A_PDU sub-




header the 16-bit FCS is calculated using the CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1), the same as for the MPDU




header FCS.









If the NC 302 does not receive the Get Privacy Setting Request M1 Message 318 from the NN, it may schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x02 and retransmit the Pre-Admission Discovery Response message 316 with the MPS Response Network IE in the ACF slot. In the following Beacon the NC 302 may then schedule another ACF slot for the Get Privacy Setting Request M1 message 318 from the NN 306. The NC 302 may, for example, repeat the retransmission of the Discovery Response message with MPS Response Network IE 316 and rescheduling of the Get Privacy Setting Request M1 Message 318 until it either receives the Get Privacy Setting Request M1 Message 318 from the NN 306 or it completes a predetermined number of repetitions. If, after the predetermined number of repetitions, the NC 302 has not received the Get Privacy Setting Request M1 Message 318, the NC 302 may then abort the MPS password exchange.
Upon reception of the Get Privacy Setting Request M1 Message 318, the NC 302 may schedule an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x21 and transmit a Get Privacy Setting Response M2 Message 320 to the NN 306. The format of an example Get Privacy Setting Response M2 message 320 is given by TABLE 7.







TABLE 7







Get Privacy Setting Response M2 Message Format









Field
Length
Usage










MPDU Header









TRANSMIT_CLOCK
32 bits 
This value is the scheduled time derived from the




corresponding AU in the MAP.


PACKET_SUBTYPE
4 bits
0x8 - Get Privacy Setting Response M2


PACKET_TYPE
4 bits
0x9 - Link control II


VERSION
8 bits
0x10


RESERVED
8 bits


SOURCE_NODE_ID
8 bits
The NC node ID when sent by the NC. 0x00




otherwise.


RESERVED
8 bits


DESTINATION_NODE_ID
8 bits
0x00


PACKET_LENGTH
16 bits 
The total length of the MPDU frame body in byes




(excluding the MPDU header).


MPDU_CONTROL_INFORMATION
32 bits 
This field is Type III reserved.


HEADER_FCS
16 bits 
MPDU header Frame Check Sequence - is




calculated over the MPDU header starting from the




Transmit_Clock field and ending with (including)




the MPDU_CONTROL_Information field. The




HEADER_FCS is calculated using CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1).







Frame Payload









DH_M2
1664 bits  
N2|| PKNC, where N2 and PKNC where PKNC:




Diffie-Hellman Public Key of the NC and N2: a




128-bit secret random number (nonce) generated by




the NC.







Payload FCS









PAYLOAD_FCS
32 bits 
For all the Management and Control MPDUs, and




for the Ethernet data packet, the 32-bit FCS is




calculated using CRC-32-IEEE 802.3 (x{circumflex over ( )}32 + x{circumflex over ( )}26 +




x{circumflex over ( )}23 + x{circumflex over ( )}22 + x{circumflex over ( )}16 + x{circumflex over ( )}12 + x{circumflex over ( )}11 + x{circumflex over ( )}10 + x{circumflex over ( )}8 +




x{circumflex over ( )}7 + x{circumflex over ( )}5 + x{circumflex over ( )}4 + x{circumflex over ( )}2 + x + 1). For the A_PDU sub-




header the 16-bit FCS is calculated using the CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1), the same as for the MPDU




header FCS.









After transmitting the Get Privacy Setting Response M2 message 320, the NC 302 may, for example, schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x22. The NN 306 may then acknowledge the reception of M2 Response message 320 by sending a Get Privacy Setting Response ACK message 322. The format of an example ACK message 322 is shown in TABLE 8.







TABLE 8







Get Privacy Setting Response Ack Message Format









Field
Length
Usage










MPDU Header









TRANSMIT_CLOCK
32 bits 
This value is the scheduled time derived from the




corresponding AU in the MAP.


PACKET_SUBTYPE
4 bits
0xA - Get Privacy Setting Response Ack


PACKET_TYPE
4 bits
0x9 - Link control II


VERSION
8 bits
0x10


RESERVED
8 bits


SOURCE_NODE_ID
8 bits
The NC node ID when sent by the NC. 0x00




otherwise.


RESERVED
8 bits


DESTINATION_NODE_ID
8 bits
0x00


PACKET_LENGTH
16 bits 
The total length of the MPDU frame body in bytes




(excluding the MPDU header).


MPDU_CONTROL_INFORMATION
32 bits 
This field is Type III reserved.


HEADER_FCS
16 bits 
MPDU header Frame Check Sequence - is




calculated over the MPDU header starting from the




Transmit_Clock field and ending with (including)




the MPDU_CONTROL_Information field. The




HEADER_FCS is calculated using CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1).







Frame Payload









RESERVED
31 bits 
Type III







Payload FCS









PAYLOAD_FCS
32 bits 
For all the Management and Control MPDUs, and




for the Ethernet data packet, the 32-bit FCS is




calculated using CRC-32-IEEE 802.3 (x{circumflex over ( )}32 + x{circumflex over ( )}26 +




x{circumflex over ( )}23 + x{circumflex over ( )}22 + x{circumflex over ( )}16 + x{circumflex over ( )}12 + x{circumflex over ( )}11 + x{circumflex over ( )}10 + x{circumflex over ( )}8 +




x{circumflex over ( )}7 + x{circumflex over ( )}5 + x{circumflex over ( )}4 + x{circumflex over ( )}2 + x + 1). For the A_PDU sub-




header the 16-bit FCS is calculated using the CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1), the same as for the MPDU




header FCS.









If the NC 302 does not receive the Get Privacy Setting Response ACK 322 from the NN 306, it may schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x21 and retransmit the Get Privacy Setting Request M2 message 320 in the ACF slot. In the following Beacon the NC 302 may then schedule another ACF slot for the Get Privacy Setting Response ACK 322 from the NN 306. The NC may, for example, repeat the retransmission of the Get Privacy Setting Request M2 message 320 and the rescheduling of the Get Privacy Setting Response ACK 322 until it either receives the ACK 322 from the NN 306 or it completes a predetermined number of repetitions. If, after the predetermined number of repetitions, the NC 302 has not received the ACK 322, the NC 302 may abort the MPS password exchange.
If the Decision from TABLE 5 is to perform an NC to NN password exchange, then upon receiving the Get Privacy Setting Response ACK message 322, the NC 302 transmits a Get Privacy Setting Response M3 message 324 to the NN 306 at least a predetermined time (e.g., in an example implementation, equal to a parameter TMPS_KEY_GEN) after the NC 302 receives the ACK message 322. The Get Privacy Setting Response M3 message 324 is transmitted in an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x23. An example format of the Get Privacy Setting Response M3 message 324 is shown in TABLE 9.







TABLE 9







Get Privacy Setting Response M3 Message Format









Field
Length
Usage










MPDU Header









TRANSMIT_CLOCK
32 bits 
This value is the scheduled time derived from the




corresponding AU in the MAP.


PACKET_SUBTYPE
4 bits
0x9 - Get Privacy Setting Response M3


PACKET_TYPE
4 bits
0x9 - Link control II


VERSION
8 bits
0x10


RESERVED
8 bits


SOURCE_NODE_ID
8 bits
The NC node ID when sent by the NC. 0x00




otherwise.


RESERVED
8 bits


DESTINATION_NODE_ID
8 bits
0x00


PACKET_LENGTH
16 bits 
The total length of the MPDU frame body in bytes




(excluding the MPDU header).


MPDU_CONTROL_INFORMATION
32 bits 
This field is Type III reserved.


HEADER_FCS
16 bits 
MPDU header Frame Check Sequence - is




calculated over the MPDU header starting from the




Transmit_Clock field and ending with (including)




the MPDU_CONTROL_Information field. The




HEADER_FCS is calculated using CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1).







Frame Payload









DH_M3
328 bits 
IV|| ENCMPSKey(Password)||




HMACDHKey(M1||M2||DH_M3*)(M1||M2||DH_M3




*) where IV is a constant string (32 replications of




0xA concatenated), ENCMPSKey(Password) is the




encrypted Password which is calculated, and




DH_M3*(=IV || ENCMPSKey(Password)) is the




authenticator attribute.


RESERVED
8 bits
Type III







Payload FCS









PAYLOAD_FCS
32 bits 
For all the Management and Control MPDUs, and




for the Ethernet data packet, the 32-bit FCS is




calculated using CRC-32-IEEE 802.3 (x{circumflex over ( )}32 + x{circumflex over ( )}26 +




x{circumflex over ( )}23 + x{circumflex over ( )}22 + x{circumflex over ( )}16 + x{circumflex over ( )}12 + x{circumflex over ( )}11 + x{circumflex over ( )}10 + x{circumflex over ( )}8 +




x{circumflex over ( )}7 + x{circumflex over ( )}5 + x{circumflex over ( )}4 + x{circumflex over ( )}2 + x + 1). For the A_PDU sub-




header the 16-bit FCS is calculated using the CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1), the same as for the MPDU




header FCS.









After transmitting the Get Privacy Setting Response M3 message 324, the NC 302 may, for example, schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x22. The NN 306 may then acknowledge the reception of the M3 message 324 by sending a Get Privacy Setting Response ACK message 326. An example format of the Get Privacy Setting Response ACK message 326 is shown in TABLE 10.







TABLE 10







Get Privacy Setting Response Ack Message Format









Field
Length
Usage










MPDU Header









TRANSMIT_CLOCK
32 bits 
This value is the scheduled time derived from the




corresponding AU in the MAP.


PACKET_SUBTYPE
4 bits
0xA - Get Privacy Setting Response Ack


PACKET_TYPE
4 bits
0x9 - Link control II


VERSION
8 bits
0x10


RESERVED
8 bits


SOURCE_NODE_ID
8 bits
The NC node ID when sent by the NC. 0x00




otherwise.


RESERVED
8 bits


DESTINATION_NODE_ID
8 bits
0x00


PACKET_LENGTH
16 bits 
The total length of the MPDU frame body in bytes




(excluding the MPDU header).


MPDU_CONTROL_INFORMATION
32 bits 
This field is Type III reserved.


HEADER_FCS
16 bits 
MPDU header Frame Check Sequence - is




calculated over the MPDU header starting from the




Transmit_Clock field and ending with (including)




the MPDU_CONTROL_Information field. The




HEADER_FCS is calculated using CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1).







Frame Payload









RESERVED
31 bits 
Type III







Payload FCS









PAYLOAD_FCS
32 bits 
For all the Management and Control MPDUs, and




for the Ethernet data packet, the 32-bit FCS is




calculated using CRC-32-IEEE 802.3 (x{circumflex over ( )}32 + x{circumflex over ( )}26 +




x{circumflex over ( )}23 + x{circumflex over ( )}22 + x{circumflex over ( )}16 + x{circumflex over ( )}12 + x{circumflex over ( )}11 + x{circumflex over ( )}10 + x{circumflex over ( )}8 +




x{circumflex over ( )}7 + x{circumflex over ( )}5 + x{circumflex over ( )}4 + x{circumflex over ( )}2 + x + 1). For the A_PDU sub-




header the 16-bit FCS is calculated using the CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1), the same as for the MPDU




header FCS.









The NN 306 may, for example, use the new password it received from the NC 302 for network admission. The NN 306 may also report the parameter ACTIVE_PSWD=the new password to the management entity of the NN 306 and the parameter ACTIVE_PRIVACYEN=Enabled if PRIVACYEN is configured as DISABLED by the management entity.
If the NC 302 does not receive the Get Privacy Setting Response ACK message 326 from the NN 306, the NC 302 may schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x21 and retransmit the Get Privacy Setting Request M3 message 324 message in the ACF slot. In the following beacon, the NC 302 may then schedule another ACF slot for the Get Privacy Setting Response ACK message 326 from the NN 306. The NC 302 may, for example, repeat the retransmission of the Get Privacy Setting Request M3 message 324 and the rescheduling of the Get Privacy Setting Response ACK message 326 until it either receives the ACK 326 from the NN 306 or it completes a predetermined number of repetitions. If after the predetermined number of repetitions the NC 302 has not received the ACK 326, the NC 302 may abort the MPS password exchange.
If the Decision of TABLE 5 is to perform an NN to NC password exchange, then upon receiving the Get Privacy Setting Response ACK message 322, the NC 302 may schedule an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x24. In accordance with an example implementation, the slot is scheduled for at least a value indicated by a variable TMPS_KEY_GEN after the NC 302 receives the ACK message 322. The NN 306 may then transmit a Get Privacy Setting Response M3 message 328 in the scheduled ACF slot. An example format of the Get Privacy Setting Response M3 message 328 is shown in TABLE 9.
If the NC 302 does not receive the Get Privacy Setting Response M3 message 328 from the NN 306, the NC 302 may schedule another ACF slot for the M3 message from the NN 306 in the next Beacon. If, after rescheduling the Get Privacy Setting Response M3 message 328 a predetermined number of times, the NC 302 has not received the M3 message 328 from the NN 306, the NC 302 may abort the MPS password exchange.
After receiving the Get Privacy Setting Request M3 message 328, the NC 302 may transmit a Get Privacy Setting Response ACK message 330 in the next ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x25 to acknowledge the reception of M3 message 328. An example format of the ACK message 330 is shown in TABLE 10. The NC 302 may then, for example, start to use the new Privacy setting for network admission. The NC 302 may also report the parameter ACTIVE_PSWD=the new password to the management entity of the NC 302 and the parameter ACTIVE_PRIVACYEN=Enabled if PRIVACYEN is configured as DISABLED by the management entity.
Various example messages discussed herein may comprise Diffie-Hellman security information, non-limiting examples of which are presented herein. It should be noted that any of a variety of alternative types of security information may be communicated without departing from the scope of this disclosure.
In accordance with an example implementation, the following parameters and notations are defined for the Diffie-Hellman Exchange:

    
    
        “A” is a secret number randomly selected by NN.
        “B” is a secret number randomly selected by the NC.
        “g” is a generator for the Diffie-Hellman exchange. The value g is known to the public.
        “P” is a prime for the Diffie-Hellman exchange. The value of P is known to the public.
        “N1” is a 128-bit secret random number (“nonce”) generated by the NN.
        “N2” is a 128-bit secret random number (“nonce”) generated by the NC.
        “PKNN” is a Diffie-Hellman Public Key of the NN.
        “PKNC” is a Diffie-Hellman Public Key of the NC.
        “DHKey” is a Diffie-Hellman Shared Key.
        “MPSKey” is an authentication key derived from DHKey, the nonces N1 and N2, and the NN's MAC address.
        “∥” denotes a concatenation operation.
    
    


In an example implementation in which the nodes are MoCA nodes operating in accordance with MoCA 2.1, the MPS operation uses 1536-bit Modular Exponential (MODP) Group for Diffie-Hellman Exchange.
The prime n p is: 2^1536−2^1472−1+2^64*{[2^1406 pi]+741804}. Its hexadecimal value is:

















FFFFFFFF
FFFFFFFF
C90FDAA2
2168C234
C4C6628B
80DC1CD1


29024E08
8A67CC74
020BBEA6
3B139B22
514A0879
8E3404DD


EF9519B3
CD3A431B
302B0A6D
F25F1437
4FE1356D
6D51C245


E485B576
625E7EC6
F44C42E9
A637ED6B
0BFF5CB6
F406B7ED


EE386BFB
5A899FA5
AE9F2411
7C4B1FE6
49286651
ECE45B3D


C2007CB8
A163BF05
98DA4836
1C55D39A
69163FA8
FD24CF5F


83655D23
DCA3AD96
1C62F356
208552BB
9ED52907
7096966D


670C354E
4ABC9804
F1746C08
CA237327
FFFFFFFF
FFFFFFFF









The generator g is 2.
In accordance with an example implementation, the NN and NC randomly generate the secret values A and B, respectively. In one such example implementation, A and B are at least 3072 bits. The Diffie-Hellman Public Keys are calculated as:

PKNN=gA mod p and PKNC=gB mod p. 

In an example implementation, the NN and the NC randomly generate the nonces N1 and N2 and exchange their nonces as well as the Diffie Hellman Public Keys. The NN then calculates the Diffie-Hellman Shared Key as:

DHKey=SHA-256(PKNCA mod p).

The NC calculates the Diffie-Hellman Shared Key as:

DHKey=SHA-256(PKNNB mod p).

Both the NN and the NC calculate the MPS Key as:

MPSKey=the first 128 bits of HMAC-SHA-256(DHKey, N1∥NNMAC∥N2),

where NNMAC is the 6-byte MAC address of the NN.

In accordance with an example implementation in which the network operates in accordance with MoCA, the Network Password length is 12 to 17 decimal digitals (96 ̃136 bits). In an alternative example implementation, the password may be longer. To encrypt a Password during a MPS session, the sender of the Password first appends zeros to the end of the Password to make it 136 bits and then encrypt it using AES-128 with MPSkey as the key.
FIG. 4 shows example message exchange sequences, and functions and tasks performed by various nodes, in accordance with various aspects of the present disclosure. In the example of FIG. 4, each node, NN 406, EN 404, NC 402, may for example maintain the following local variables in addition to those that a node would normally maintain (e.g., in accordance with its operating protocol, for example the MoCA 2.0 specification). Similar to the example shown in FIG. 3, in the example shown in FIG. 4, each node may maintain a PBState local variable, a PairedState local variable, an ACTIVE_PRIVACYEN configuration parameter, an ACTIVE_PSWD configuration parameter and a PBNode local variable. However, in addition to such example local variables, nodes operating in accordance with the example aspects shown in FIG. 4 may also maintain an MPSReqRx local variable and a PBNewNode local variable. The MPSReqRx local variable may, for example, be set to either “YES” or “NO”. Initially, the value may be set to NO. The value may then be set to YES under the example conditions indicated below. The value of the PBNewNode local variable may, for example, be set to indicate the Globally Unique Identifier (GUID) of an NN sending an MPS Request Network IE to an NC when MPSReqRx is set to NO. This example is described in more detail herein.
The following may, for example, apply to an NN 406 in one of the following example states. In a first example state, the NN 406 has been recently powered up, but has not yet either joined a network or moved to the Beacon Phase. The Beacon Phase may, for example, be the state in which the node starts to send out beacons in an attempt to form a new network. In a second example state, the NN 406 is in the Beacon Phase, and the NN 406 is not sending a beacon nor attempting to admit another node to form a network.
In this case, in an example implementation, if an MPS triggering event occurs (e.g., the user pushes the MPS button on the NN 406) with the NN MPS enabled, the NN 406 may check the state of the PBState local variable. If the PBState local variable has been set to PUSHED (not shown in FIG. 4), then the NN 406 will ignore the triggering event. However, if the value of the local variable PBState has not been set to PUSHED (e.g., the variable is set to CLEAR) 408, then the NN 406 will set the PBState local variable to PUSHED, start an MPS timer (e.g., a walk timer), and start or restart its network search process. If the timer reaches MPSWALK_TIME, then the NN 406 may set the local variable PBState to CLEAR and reset the MPS timer.
If, however, the NN 406 detects a beacon from the NC 402 prior to the timer reaching MPSWALK_TIME, and PBState is equal to CLEAR (a condition not shown in FIG. 4), then the NN 406 may assume that there is currently no MPS session in progress. Accordingly, the NN 406 may perform node admission in a conventional manner. If during the node admission process with PBState equal to CLEAR, an MPS trigger event occurs, the NN 406 may abort the admission process and restart the network search (not shown in FIG. 4).
Alternatively, if the local variable PBState of the NN 406 is set to PUSHED when the NN 406 detects a beacon 410, then the NN 406 may wait for a beacon 412 that schedules an ACF slot with ACF_TYPE equal to 0x0F and ADDITIONAL_ACF_TYPE equal to 0x20. If a beacon 412 is received that has scheduled the anticipated ACF slot with ACF_TYPE equal to 0x0F and ADDITIONAL_ACF_TYPE equal to 0x20 within a predetermined amount of time, the NN 406 may, during that ACF slot, send a Pre-Admission Discovery Request message with an MPS Request Network IE 414 having the example format indicated by TABLE 12.







TABLE 12







MPS Request Network IE Format









Field
Length
Value










IE Header









TYPE
8 bits
0x09- MPS Request Network IE


LENGTH
8 bits
0x0E







IE Payload









RESERVED
12 bits 
Type III


MPS_PARAMETERS
4 bits
Bit 2 - Privacy. MUST reflect the value of




ACTIVE_PRIVACYEN




0b0 = Disabled




0b1 = Enabled




Bit 1 - Receive Privacy. If PairedState = un-




Paired: MUST reflect the value of the Node's




MPSPRIVACY—RECEIVE




0b0 = Disabled




0b1 = Enabled




MUST be set to 0b0 if the PairedState =




Paired.




Bit 0 - Downgrade Privacy. If Bit 1 is set to




0b1: MUST reflect the value of the Node's




MPSPRIVACY— DOWN




0b0 = Disabled




0b1 = Enabled




Reserved Type III when Bit 1 = 0b0.


GUID
64 bits 
64 bit MAC address of the device


ECDH_PUBLIC_KEY_X
256 bits 
x coordinate of Public key


ECDH_PUBLIC_KEY_Y
256 bits 
y coordinate of Public key









The NN 406 will load the NN's MPS parameters into the MPS_PARAMETER field. The GUID field will carry the GUID of the NN 406. In addition, the ECDH_PUBLIC_KEY_X field will carry the value of the x-coordinate of the ECDH public key, and the ECDH_PUBLIC_KEY_Y field will carry the value of the y-coordinate of the ECDH public key. If the NN 406 does not receive an ACF slot for sending an MPS Request Message before the predetermined time expires, then the NN 406 may conclude that the admission was not successful and continue its network search.
Assuming that the NN 406 receives a beacon 412 indicating that an ACF slot has been scheduled by the NC 402 and the NN 406 sends the Discovery Request message comprising the MPS Request Network IE 414, the NN 406 may then monitor the ACF slot 416 scheduled in the next beacon 418 to see whether a Pre-admission Discovery Response message with an MPS Response Network IE 416 is sent from the NC 402. If the NN 406 does not receive the response from the NC 402 in the next ACF slot 416, the NN 406 may, for example, use the next ACF slot with ACF_TYPE equal to 0x0F and ADDITIONAL_ACF_TYPE equal to 0x20 to retransmit a Discover Request Message (not shown in FIG. 4).
If, however, the NN 406 receives a Pre-admission Discovery Response message 416 from the NC 402 in the next ACF slot, the NN 406 may determine the value of the CODE field of the MPS Response Network IE 416. If the value of the CODE field is 0x0 (e.g., indicating that the NC 402 either has MPS disabled or the NC 402 has not been triggered), the NN 406 may conclude that the admission was not successful and may continue searching for a network. Alternatively, if the value of the CODE field is 0x1 (e.g., indicating MPS is enabled and the NC 402 has been triggered), the NN 406 may reset the MPS timer and use the values of the MPS_PARAMETERS that the NN 406 sent to the NC 402 to determine how to proceed, for example based on the Decision Matrix of TABLE 5.
If the Decision Matrix of TABLE 5 indicates “Node Privacy Admission”, then the NN 406 may continue node admission using the NN's active privacy settings. If the Decision Matrix indicates “FAILED”, then the NN 406 may conclude that the admission was not successful and continue the network search. The NN 406 may also report the pairing failure to its management entity using the MPSPAIR_FAILED parameter. In addition, the NN 406 may set the PBState to CLEAR.
If the Decision Matrix indicates “No Privacy Admission”, then the NN 406 may set the ACTIVATE PRIVACYEN local variable to DISABLE, report the ACTIVATE PRIVACYEN local variable to the NN's management entity and continue to node admission.
If the Decision Matrix indicates “NC to NN PSWD Exchange”, then the NN 406 may perform an MPS PSWD exchange during which the NC 402 will provide the password to the NN 406.
If Decision Matrix indicates “NN to NC PSWD Exchange” the NN 406 may perform an MPS PSWD exchange during which the NN 406 may provide the password to the NC 402.
The NN 406 may set the local variable PBState to CLEAR when it completes the admission process. If, however, the admission fails, the NN 406 may set the local variable PBState to CLEAR, for example as soon as the NN 406 aborts the admission process.
FIG. 5 shows example message exchange sequences, and functions and tasks performed by various nodes, in accordance with various aspects of the present disclosure. Such operation may, for example, be performed by various nodes when operating in a Beacon Phase of a network search, but the scope of the present disclosure is not limited thereto.
If an MPS trigger event occurs in a node that is in the Beacon Phase and sending beacons 509, the beaconing node 502 may check the status of the MPSEN local variable and the PBState local variable. If the PBState local variable is set to PUSHED or the MPSEN local variable is set to DISABLE, the beaconing node 502 may for example ignore the MPS trigger event. However, if the PBState local variable is set to CLEAR and the MPSEN local variable is set to ENABLE 508, the beaconing node 502 may for example start an MPS timer and restart its network search (e.g., leave Beacon Phase). If the MPS timer reaches the value MPSWALK_TIME the node 502 will set PBState to CLEAR and reset the MPS timer.
Alternatively, if the node 502 receives a Pre-Admission Discover Request message 511 with an MPS Request Network IE from an NN 506 during an ACF slot scheduled by the beacon 509, the node 502 will schedule an ACF slot in the next beacon 512 to allow transmission of a Pre-admission Discovery Response to the NN 506. The node 502 then transmits the Pre-admission Discovery Response message 514 to the NN 506 during the ACF slot. In the Pre-admission Discovery Response message 514, the CODE field is set to 0x0 if the PBState local variable in the node 502 is set to CLEAR.
If the PBState local variable in the node 502 is set to PUSHED, the node 502 will check the state of the MPSReqRx local variable, the value sent in the GUID field of the MPS Request Network IE, and the public key sent in the MPS Request Network IE to determine the value to set the CODE field. If the MPSReqRx local variable is set to YES and the value of the GUID field sent by the NN 506 within the MPS Request Network IE 511 is not equal to the value of held in the PBNewNode local variable, then the CODE field is set to 0x0. In addition, if the public key sent in the MPS Request Network IE 511 does not match the key previously stored by the NC 502, the CODE field is set to 0x0. Otherwise, the CODE field is set to 0x1.
Bit 2 of the MPS_PARAMETER field in the Discovery Response 514 is set to reflect the value of the node's ACTIVE_PRIVACYEN configuration parameter. Bit 1 of the MPS_PARAMETER field in the response 514 is set to 0b0 if the value of PairedState is PAIRED. However, if the value of PairedState is set to UNPAIRED, bit 1 will reflect the value of the Node's MPSPRIVACY_RECEIVE configuration parameter. If bit 1 of the MPS_PARAMETER field in the response 514 is set to 0x1, then bit 0 of the MPS_PARAMETER field in the response 514 is set to reflect the value of the node's MPSPRIVACY_DOWN configuration parameter.
If the CODE field in the Discovery Response 514 is set to 0x0 and the MPSReqRx is set to NO, then the node 502 will start an MPS timer, set the MPSReqRx value to YES, set the value of PBNewNode to the NN's GUID (as determined from the MPS Request Network IE 511) and store the NN's public Key sent in the MPS Request Network IE 511.
Alternatively, if the CODE field of the response 514 is set to 0x0, but the MPSReqRx is set to YES, the node 502 will continue normal operation and no action will be taken.
If the CODE field of the Discovery Response 514 is set to 0x1, the node 502 will reset the MPS timer and use the Decision Matrix of TABLE 5 to determine how to proceed.
If Decision Matrix indicates “Node Privacy Admission” the node 502 will perform node admission using the Node's privacy settings (ACTIVE_PRIVACYEN and ACTIVE_PSWD).
If Decision Matrix indicates “Failed” the node 502 will set PBState to CLEAR, set MPSReqRx to NO, report the pairing failure to the management entity using MPSPAIR_FAIL, and continue normal operation.
If Decision Matrix indicates “No Privacy Admission”, the node 502 will set ACTIVE_PRIVACYEN to DISABLED, report ACTIVE_PRIVACYEN=DISABLED to the management entity, and continue to node admission.
If Decision Matrix indicates “NC to NN PSWD Exchange”, the node 502 will continue to MPS PSWD exchange, during which the Node will provide the password to the NN.
If Decision Matrix indicates “NN to NC PSWD Exchange”, the node 502 will continue to MPS PSWD exchange, during which the NN will provide the password to the node 502.
The node 502 will set PBState to CLEAR upon completing the admission of the NN 506. Alternatively, if admission fails, the node 502 will set PBState to CLEAR as soon as the node 502 stops the admission process.
FIG. 6 shows message exchange sequences, and functions and tasks performed by various nodes, in accordance with various aspects of the present disclosure. In an example implementation, if the MPSEN of the EN 604 is set to DISABLE, then the EN 604 may for example ignore any MPS trigger event. However, when the EN 604 has its MPS enabled and is triggered with an MPS triggering event 632, the EN 604 may for example send an MPS Request PIE 610 in an RR to the NC 602 as shown in FIG. 6. When the NC 602 receives the MPS Request PIE 610, if the PBState is equal to CLEAR and the MPSReqRx is equal to NO, the NC 602 will set PBState to PUSHED, set the PBNode local variable to the value of the node ID for the EN 604 as indicate in the MPS Request Protocol IE 610, start an MPS timer, and broadcast an MPS Session Notification Message 612 to all the ENs of the network. An example format of the MPS Session Notification Message is provided in TABLE 11. In an example implementation, the NC 602 will disable any handoff of the NC functionality during an MPS session. In such case, no MPS Session Notification Message need be sent to the other ENs in the network.







TABLE 11







MPS Session Notification Message Format









Field
Length
Usage










MPDU Header









TRANSMIT_CLOCK
32 bits 
This value is the scheduled time derived from the




corresponding AU in the MAP.


PACKET_SUBTYPE
4 bits
0xA - MPS Session Notification


PACKET_TYPE
4 bits
0x9 - Link control II


VERSION
8 bits
0x10


RESERVED
8 bits


SOURCE_NODE_ID
8 bits
The NC node ID when sent by the NC. 0x00




otherwise.


RESERVED
8 bits


DESTINATION_NODE_ID
8 bits
0x00


PACKET_LENGTH
16 bits 
The total length of the MPDU frame body in bytes




(excluding the MPDU header).


MPDU_CONTROL_INFORMATION
32 bits 
This field is Type III reserved.


HEADER_FCS
16 bits 
MPDU header Frame Check Sequence - is




calculated over the MPDU header starting from




the Transmit_Clock field and ending with




(including) the MPDU_CONTROL_Information




field. The HEADER_FCS is calculated using




CRC-16 (x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1).







Frame Payload









TYPE
4 bits
Type III reserved.


MPS_STATUS_UPDATE
4 bits
0x0 - First MPS Trigger - Network




0x1 - First MPS Trigger - NN




0x2 - Second MPS Trigger - Network




0x3 - End MPS session




Other values reserved.


PB_NODE
8 bits
If MPS_STATUS_UPDATE = 0x0 or 0x2, the




value of PBNode; Otherwise, Type III reserved.


RESERVED
16 bits 
Type III


PB_NEW_NODE
64 bits 
If MPS_STATUS_UPDATE = 0x1, the value of




PBNewNode; Otherwise, the field is not sent.


ECDH_PUBLIC_KEY_X
256 bits 
If MPS_STATUS_UPDATE = 0x1, the value is




copied from the ECDH_PUBLIC_KEY_X field in




the received MPS Request Network IE; Otherwise,




the field is not sent.


ECDH_PUBLIC_KEY_Y
256 bits 
If MPS_STATUS_UPDATE = 0x1, the value is




copied from the ECDH_PUBLIC_KEY_Y field in




the received MPS Request Network IE; Otherwise,




the field is not sent.







Payload FCS









PAYLOAD_FCS
32 bits 
For all the Management and Control MPDUs, and




for the Ethernet data packet, the 32-bit FCS is




calculated using CRC-32-IEEE 802.3 (x{circumflex over ( )}32 + x{circumflex over ( )}26 +




x{circumflex over ( )}23 + x{circumflex over ( )}22 + x{circumflex over ( )}16 + x{circumflex over ( )}12 + x{circumflex over ( )}11 + x{circumflex over ( )}10 + x{circumflex over ( )}8 +




x{circumflex over ( )}7 + x{circumflex over ( )}5 + x{circumflex over ( )}4 + x{circumflex over ( )}2 + x + 1). For the A_PDU sub-




header the 16-bit FCS is calculated using the




CRC-16 (x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1), the same as for the




MPDU header FCS.









The MPS_STATUS_UPDATE field may, for example, set to 0x0 and the PB_NODE field may, for example, be set to the value of the PBNode local variable.
If the value of PBState is CLEAR, but the value of MPSReqRx is YES, then the NC 602 may set the value of PBState to PUSHED, set the value of PBNode to the node ID of the node that sent the MPS Request Protocol IE 610 and broadcast an MPS Session Notification Message having the MPS_STATUS_UPDATE field loaded with the value 0x2 and the PBNode field loaded with the value of the NC's PBNode local variable.
If the value of PBState is PUSHED, then the NC 602 may for example determine whether the value of PBNode is equal to the node ID sent in the MPS Request Protocol IE 610. If so, then the NC 602 may ignore the request and take no action. However, if the value of PBNode is not equal to the node ID sent in the MPS Request Protocol IE 610, the NC 602 may reset the MPS timer, set the PBState to CLEAR and the MPSReqRx to NO, and broadcast an MPS Session Notification Message with MPS_STATUS_UPDATE field equal to 0x3.
If the MPS timer in the NC 602 reaches MPSWALK_TIME, the NC 602 may for example set PBState to CLEAR, set MPSReqRx to NO, reset the MPS timer, and send an MPS Session Notification Message with MPS_STATUS_UPDATE field loaded with the value 0x3. If, however, an NN 606 is triggered by an MPS trigger event 634 (e.g., the MPS button on the NN 606 is pressed), the NN 606 may send to the NC 602 a Pre-admission Discovery Request Message with a MPS Request Network IE 614. The NC 602 may then transmit the next Beacon with an ACF slot scheduled to allow the NC 602 to transmit a Pre-admission Discovery Response Message with an MPS Response Network IE 616 (see TABLE 4 above) to the NN 606.
In the MPS Response Network IE 616, the NC 602 may, for example, set the CODE field and the Node's MPS parameters in the MPS_PARAMETER field as follows:
If PBState is set to CLEAR, then the NC may set the CODE field to 0x0. However, if the PBState local variable is set to PUSHED, MPSReqRx is set to YES, and the GUID of the NN 606 that sent the MPS Request Network IE 614 is not equal to the value of the PBNewNode local variable or the public key that is stored is not equal to the public key sent in the MPS Request Network IE 614, then the CODE may be set to 0x0. If the PBState local variable is set to PUSHED and MPSReqRx is set to NO, or MPSReqRx is set to YES and the GUID of the NN 606 that sent the MPS Request Network IE 614 is equal to the value of the PBNewNode local variable and the public key matches the stored public key, then the CODE may be set to 0x1.
In addition, bit 2 of the MPS_PARAMETER field in the MPS Response Network IE 616 may be set to reflect the value of ACTIVE_PRIVACYEN, bit 1 may be set to 0b0 and bit 0 may be set to 0b0.
In addition, in response to receiving the Pre-admission Discovery Request Network IE 614, the NC 602 may determine the values of the CODE field and MPS_PARAMETERS field of the MPS Response Network IE 616 it sent to the NN 606 and the last setting of the MPSReqRx local variable and use those values to determine how to proceed.
If the value of the CODE field of the MPS Response Network IE 616 is equal to 0x0 and MPSReqRx is set to NO, then the NC 602 may for example start a MPS timer, set MPSReqRx to YES, set PBNewNode to the NN's GUID, store the NN's Public Key (as sent in the MPS Request Network IE 614), and broadcast a Network MPS Session Notification (see TABLE 11) with the value 0x1 loaded in the MPS_STATUS_UPDATE field.
If the CODE field of the MPS Response Network IE 616 is equal to 0x0 and MPSReqRx is set to YES, then the NC 602 may for example continue normal operation and no action is required.
If the CODE field of the MPS Response Network IE 616 is 0x1, then the NC 602 may for example reset the MPS timer, set PBState to CLEAR, set MPSReqRx to NO, send a MPS Session Notification in which the MPS_STATUS_UPDATE field is set to 0x3. In addition, the NC 602 may use the Decision Matrix of TABLE 5, and identify the Decision indicated by the applying the received and transmitted MPS_PARAMETERS.
If the Decision Matrix of TABLE 5 indicates “Node Privacy Admission”, then the NC 602 may for example continue normal operation.
If the Decision Matrix of TABLE 5 indicates “Failed” then the NC 602 may for example report the pairing failure to the management entity using MPSPAIR_FAIL and continue normal operation.
If the Decision Matrix of TABLE 5 indicates “NC to NN PSWD Exchange”, then the NC 602 may for example perform a MPS PSWD exchange in which the NC 602 will provide the password to the NN 606.
In accordance with an example implementation, the NC 602 will not transmit a MPS Session Notification message if there are no MOCA 2.1 nodes present in the network. However, in an alternative implementation, such message may be transmitted regardless of what nodes are present. If the NC 602 drops from the network for any reason, the NC 602 may for example set PBState to CLEAR, set MPSReqRx to NO and reset the MPS timer if it is running
FIG. 7 shows example message exchange sequences, and functions and tasks performed by various nodes, in accordance with various aspects of the present disclosure. For example, the example message exchange sequences may take place between an NN 706 and an NC 702 during a password exchange. In accordance with an example implementation, when the decision indicated by the Decision Matrix of TABLE 5 indicates that a password exchange is to be carried out, the exchange is carried out as follows. If the exchange is not completed successfully, the NN 706 will set the PBState local variable to CLEAR and the NC 702 will set the MPSReqRx variable to NO. The NC 702 will then resume normal operation and the NN 706 will resume performing a network search.
When the decision is made to perform a password exchange, the NC 702 may for example transmit the next beacon with an ACF scheduled with ACF_TYPE set to 0x0F and ADDITIONAL_ACF_TYPE set to 0x21. The NN 706 may then transmit an MPS ACK message 708. TABLE 13 provides an example format for the MPS ACK Message 708.







TABLE 13







MPS ACK Message Format









Field
Length
Usage










MPDU Header









TRANSMIT_CLOCK
32 bits 
This value is the scheduled time derived from the




corresponding AU in the MAP.


PACKET_SUBTYPE
4 bits
0x9 - MPS ACK


PACKET_TYPE
4 bits
0x9 - Link control II


VERSION
8 bits
0x10


RESERVED
8 bits


SOURCE_NODE_ID
8 bits
The NC node ID when sent by the NC. 0x00




otherwise.


RESERVED
8 bits


DESTINATION_NODE_ID
8 bits
0x00


PACKET_LENGTH
16 bits 
The total length of the MPDU frame body in bytes




(excluding the MPDU header).


MPDU_CONTROL_INFORMATION
32 bits 
This field is Type III reserved.


HEADER_FCS
16 bits 
MPDU header Frame Check Sequence - is




calculated over the MPDU header starting from the




Transmit_Clock field and ending with (including)




the MPDU_CONTROL_Information field. The




HEADER_FCS is calculated using CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1).







Frame Payload









RESERVED
31 bits 
Type III


RESPONSE TYPE
1 bit 
0b0 - ACK




Other value is reserved.


GUID
64 bits 
64 bit MAC address of the device







Payload FCS









PAYLOAD_FCS
32 bits 
For all the Management and Control MPDUs, and




for the Ethernet data packet, the 32-bit FCS is




calculated using CRC-32-IEEE 802.3 (x{circumflex over ( )}32 + x{circumflex over ( )}26 +




x{circumflex over ( )}23 + x{circumflex over ( )}22 + x{circumflex over ( )}16 + x{circumflex over ( )}12 + x{circumflex over ( )}11 + x{circumflex over ( )}10 + x{circumflex over ( )}8 +




x{circumflex over ( )}7 + x{circumflex over ( )}5 + x{circumflex over ( )}4 + x{circumflex over ( )}2 + x + 1). For the A_PDU sub-




header the 16-bit FCS is calculated using the CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1), the same as for the MPDU




header FCS.









If the NC 702 does not receive the MPS ACK message 708 from the NN 706, the NC 702 may schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x02. The NC 702 may then retransmit a Pre-Admission Discovery Response with the MPS Response Network IE that lead to the password exchange. The Pre-Admission Discovery Response with the MPS Response Network IE will be sent in the ACF slot (not shown in FIG. 7). In the following Beacon, the NC 702 may then schedule another ACF slot for the MPS ACK message from the NN 706. The NC 702 may repeat the retransmission of the MPS Response and rescheduling of the MPS ACK message 708 until it either receives the MPS ACK message 708 from the NN 706 or the NC 702 completes a predetermined number of repetitions. If after predetermined number of repetition the NC 702 does not receive the MPS ACK message 708, the NC 702 may abort the MPS password exchange.
Upon successful reception of the MPS ACK message 708, the NC 702 may schedule an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x02 and transmit a Pre-admission Discovery Response 710 to the NN 706. The Discovery Response 710 may, for example, comprise an MPS NC Public Key Network IE. An example format of the MPS NC Public Key Network IE is shown in TABLE 14.







TABLE 14







NC Public Key Network IE Format









Field
Length
Value










IE Header









TYPE
8 bits
0x0B - NC Public Key Network IE


LENGTH
8 bits
0x0E







IE Payload









NODE_ID
8 bits
The ID of the NC


RESERVED
8 bits
Type III


REQUESTING_NODE_GUID
64 bits 
This field is copied from the last received MPS




ACK message.


ECDH_PUBLIC_KEY_X
256 bits 
x coordinate of the NC's ECDH public key


ECDH_PUBLIC_KEY_Y
256 bits 
y coordinate of the NC's ECDH public key









After transmitting the Pre-admission Discovery Response 710 with the NC Public Key Network IE, the NC 702 may schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x21. The NN 706 may then acknowledge the reception of NC Public Key by sending a Public Key ACK message 712 in the scheduled slot. An example format of the ACK message 712 (e.g., a Public Key ACK message or MPS ACK message) is shown in TABLE 15







TABLE 15







MPS ACK Message Format









Field
Length
Usage










MPDU Header









TRANSMIT_CLOCK
32 bits 
This value is the scheduled time derived from the




corresponding AU in the MAP.


PACKET_SUBTYPE
4 bits
0x9 - MPS ACK


PACKET_TYPE
4 bits
0x9 - Link control II


VERSION
8 bits
0x10


RESERVED
8 bits


SOURCE_NODE_ID
8 bits
The NC node ID when sent by the NC. 0x00




otherwise.


RESERVED
8 bits


DESTINATION_NODE_ID
8 bits
0x00


PACKET_LENGTH
16 bits 
The total length of the MPDU frame body in bytes




(excluding the MPDU header).


MPDU_CONTROL_INFORMATION
32 bits 
This field is Type III reserved.


HEADER_FCS
16 bits 
MPDU header Frame Check Sequence - is




calculated over the MPDU header starting from the




Transmit_Clock field and ending with (including)




the MPDU_CONTROL_Information field. The




HEADER_FCS is calculated using CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1).







Frame Payload









RESERVED
31 bits 
Type III


RESPONSE_TYPE
1 bit 
0b0 - ACK




Other value is reserved.


GUID
64 bits 
64 bit MAC address of the device







Payload FCS









PAYLOAD_FCS
32 bits 
For all the Management and Control MPDUs, and




for the Ethernet data packet, the 32-bit FCS is




calculated using CRC-32-IEEE 802.3 (x{circumflex over ( )}32 + x{circumflex over ( )}26 +




x{circumflex over ( )}23 + x{circumflex over ( )}22 + x{circumflex over ( )}16 + x{circumflex over ( )}12 + x{circumflex over ( )}11 + x{circumflex over ( )}10 + x{circumflex over ( )}8 +




x{circumflex over ( )}7 + x{circumflex over ( )}5 + x{circumflex over ( )}4 + x{circumflex over ( )}2 + x + 1). For the A_PDU sub-




header the 16-bit FCS is calculated using the CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1), the same as for the MPDU




header FCS.









If the NC 702 does not receive the Public Key ACK from the NN 706, the NC 702 may, for example, schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x02 and retransmit the Pre-admission Discovery Response 710 with its Public Key in an MPS NC Public key Network IE in the scheduled ACF slot. In the following Beacon the NC 702 may schedule another ACF slot for the Public Key ACK from the NN 706. The NC 702 may repeat the retransmission of the Discovery Response message 710 with the NC Public Key Network IE and rescheduling of the NC Public Key ACK 712 until either it receives the ACK 712 from the NN 706 or it completes a predetermined number of repetitions. If after predetermined number of repetitions, the NC 702 does not receive the ACK 712, the NC 702 may consider the exchange to have been unsuccessful and abort the MPS password exchange.
If the password exchange is an NC to NN PSWD Exchange, then upon receiving the Public Key ACK message 712 from the NN 706, the NC 702 may transmit an MPS Network Password message 714 to the NN 706, for example at least a first predetermined number of seconds and not more than a second predetermined number of seconds after the receipt of the MPS ACK 712. In one example implementation, the first predetermined number of seconds may be determined by a local variable, TMPS_KEY_GEN_MIN and the second predetermined time may be determined by a local variable, TMPS_KEY_GEN_MAX. The MPS Network Password message 714 may, for example, be transmitted in an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x22. An example format of the MPS Network Password message 714 is provided in TABLE 16.







TABLE 16







MPS Network Password Message Format









Field
Length
Usuage










MPDU Header









TRANSMIT_CLOCK
32 bits 
This value is the scheduled time derived from the




corresponding AU in the MAP.


PACKET_SUBTYPE
4 bits
0x8 - MPS Network Password


PACKET_TYPE
4 bits
0x9 - Link control II


VERSION
8 bits
0x10


RESERVED
8 bits


SOURCE_NODE_ID
8 bits
The NC node ID when sent by the NC. 0x00




otherwise.


RESERVED
8 bits


DESTINATION_NODE_ID
8 bits
0x00


PACKET_LENGTH
16 bits 
The total length of the MPDU frame body in bytes




(excluding the MPDU header).


MPDU_CONTROL_INFORMATION
32 bits 
This field is Type III reserved.


HEADER_FCS
16 bits 
MPDU header Frame Check Sequence - is




calculated over the MPDU header starting from the




Transmit_Clock field and ending with (including)




the MPDU_CONTROL_Information field. The




HEADER_FCS is calculated using CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1).







Frame Payload









NETWORK_PASSWORD
512 bits 
The network password. If the password length is




less than 64 bytes, pad the password to 64 bytes




with leading ASCII zeros.







Payload FCS









PAYLOAD_FCS
32 bits 
For all the Management and Control MPDUs, and




for the Ethernet data packet, the 32-bit FCS is




calculated using CRC-32-IEEE 802.3 (x{circumflex over ( )}32 + x{circumflex over ( )}26 +




x{circumflex over ( )}23 + x{circumflex over ( )}22 + x{circumflex over ( )}16 + x{circumflex over ( )}12 + x{circumflex over ( )}11 + x{circumflex over ( )}10 + x{circumflex over ( )}8 +




x{circumflex over ( )}7 + x{circumflex over ( )}5 + x{circumflex over ( )}4 + x{circumflex over ( )}2 + x + 1). For the A_PDU sub-




header the 16-bit FCS is calculated using the CRC-16




(x{circumflex over ( )}16 + x{circumflex over ( )}15 + x{circumflex over ( )}2 + 1), the same as for the MPDU




header FCS.









In accordance with an example implementation, the message 714 may be encrypted using AES with an MPSKey. Alternatively, just the field carrying the password might be encrypted.
After transmitting the Network Password message 714, the NC 702 may schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x21. The NN 706 may then acknowledge the reception of Network Password message 714 by sending an MPS ACK message 716.
The NN 702 may then use the new password it received from the NC 702 for network admission. The NN 706 may also report a parameter ACTIVE_PSWD with a value equal to the new password to its management entity, and a parameter ACTIVE_PRIVACYEN having a value equal to “Enabled” if PRIVACYEN is configured as DISABLED by the management entity.
If the NC 702 does not receive the MPS ACK 716 from the NN 706, the NC 702 may schedule in the next Beacon an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x22 and retransmit the Network Password message 714. In the following Beacon, the NC 702 may schedule another ACF slot for the MPS ACK 716 from the NN 706. The NC 702 may, for example, repeat the retransmission of the Network Password message 714 and rescheduling of the MPS ACK until it either receives the ACK 716 from the NN 706 or it completes a predetermined number of repetitions. If after the predetermined number of repetition the NC 702 does not receive the ACK 716, the NC 702 may abort the MPS password exchange.
If the password exchange is an NN to NC PSWD Exchange, then upon receiving the Public Key ACK message 712, the NC 702 may schedule an ACF slot with ACF_TYPE=0x0F and ADDITIONAL_ACF_TYPE=0x23, for example between TMPS_KEY_GEN MIN and TMPS_KEY_GEN MAX after it receives the ACK message 712. The NN 702 may transmit a Network Password message 718 in the scheduled ACF slot. In accordance with one embodiment, the message 718 may be encrypted using AES with the MPSKey.
If the NC 702 does not receive the Network Password message 718 from the NN 702, the NC 702 may schedule another ACF slot for the Network Password message 718 from the NN 706 in the next Beacon. If after rescheduling the Network Password message 718 for a predetermined number of times the NC 702 does not receive the Network Password message 718 from the NN 706, the NC 702 may abort the MPS password exchange.
Once the NC 702 receives the Network Password message 718 from the NN 706, the NC 702 may start using the new Privacy setting based on ACTIVE_PRIVACYEN and ACTIVE_PSWD for network admission. The NC 702 may also report the ACTIVE_PSWD having a value equal to the new password to the management entity and ACTIVE_PRIVACYEN having a value equal to “Enabled” if PRIVACYEN is configured as DISABLED by the management entity.
In accordance with an example implementation in accordance with various aspects of the present disclosure, MPS keys are calculated as follows:
The example implementation may, for example, use ECDH P-256 Elliptic Curve Diffie Hellman as the cryptographic key exchange protocol. The following parameters and notations may be used for the Elliptic Curve Diffie-Hellman Exchange:

    
    
        dNN: a private key randomly selected by the NN
        dNC: a private key randomly selected by the NC
        QNN: the 2x256-bit Diffie-Hellman Public Key of the NN
        QNC: the 2x256-bit Diffie-Hellman Public Key of the NC
        DHKey: a 256-bit Diffie-Hellman Shared Secret Key
        MPSKey: a 128-bit AES key derived from DHKey which is used to encrypt the MPS Network Password message and ACK message
        G: the base point of ECDH with x coordinate of Gx and y coordinate of Gy
        ∥: the concatenation operation
    
    


The NN 706 and NC 702 randomly generate the private keys dNN and dNC, respectively. The Diffie-Hellman Public Keys are calculated as:

QNN=dNN*G and QNC=dNC*G. 

The NN then calculates the Diffie-Hellman Shared Secret Key as:

DHKey=dNN*GNC 

The NC then calculates the Diffie-Hellman Shared Secret Key as:

DHKey=dNC*GNN 

Both the NN 706 and the NC 702 calculate the MPS Key as:

MPSKey=the first 128 bits of HMAC-SHA-256 (DHKey, PKNN∥NNMAC∥PKNC), where NNMAC is the 6-byte MAC address of the NN 706.

In summary, various aspects of this disclosure provide systems and methods for securing a network, for admitting new nodes into an existing network, and/or securely forming a new network. While the foregoing has been described with reference to certain aspects and examples, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from its scope. Therefore, it is intended that the disclosure not be limited to the particular example(s) disclosed, but that the disclosure will include all examples falling within the scope of the appended claims.

## Claims

1. A network comprising:
a first node; and
a second node, wherein:
the first node comprises at least one circuit operable to, at least:
send a first message to the second node comprising information that indicates protected setup has been triggered;
send a second message to the second node indicating a slot in which the second node is to acknowledge receipt of the first message; and
determine whether the first node is going to send a password to the second node or whether the second node is going to send a password to the first node; and

the second node comprises at least one circuit operable to, at least:
receive the first message;
receive the second message;
send a message to the first node in the slot specified by the second message acknowledging receipt of the first message; and
determine whether the first node is to send a password to the second node or whether the second node is to send a password to the first node.

2. The network of claim 1, wherein the at least one circuit of the first node operates to, if the second node acknowledges receipt of the first message, then send to the second node a third message comprising public key information, and a fourth message indicating a slot in which the second node is to acknowledge receipt of the third message.

3. The network of claim 2, wherein the at least one circuit of the first node operates to wait at least a first predetermined amount of time after receiving the fourth message before exchanging password information with the second node.

4. The network of claim 1, wherein the at least one circuit of the first node operates to, if it is determined that the first node is to send a password to the second node, then:
transmit a third message to the second node communicating the password to the second node; and
transmit a fourth message indicating a slot in which the second node is to acknowledge receipt of the third message.

5. The network of claim 1, wherein if it is determined that the second node is to send a password to the first node, then:
the at least one circuit of the first node operates to transmit a third message to the second node indicating a slot in which the second node is to send a fourth message communicating the password to the first node; and
the at least one circuit of the second node operates to transmit the fourth message communicating the password to the first node.

6. The network of claim 5, wherein the third message specifies that the fourth message be of a particular type.

7. A network node comprising:
at least one circuit operable to, at least:
send a first message to a second node comprising information that indicates protected setup has been triggered;
send a second message to the second node indicating a slot in which the second node is to acknowledge receipt of the first message;
receive a message from the second node acknowledging receipt of the first message by the second node;
determine whether to send a password to the second node or whether to receive a password from the second node;
if it is determined to send a password to the second node, then send a password of the network node to the second node; and
if it is determined to receive a password from the second node, then receive a password of the second node from the second node.

8. The network node of claim 7, wherein the second message specifies a particular type of acknowledgement message to be transmitted by the second node in the indicated slot.

9. The network node of claim 8, wherein the at least one circuit operates to, if the network node does not receive the particular type of acknowledgement message before a predetermined time has passed, then resend the first and second messages.

10. The network node of claim 7, wherein the at least one circuit operates to, if the second node acknowledges receipt of the first message, then transmit to the second node a third message comprising public key information and a fourth message indicating a slot in which the second node is to acknowledge receipt of the third message.

11. The network node of claim 10, wherein the at least one circuit operates to wait at least a first predetermined amount of time after the second node acknowledges receipt of the third message before exchanging password information with the second node.

12. The network node of claim 7, wherein the first message is a Discovery Response message comprising an information element indicating that protected setup has been triggered.

13. The network node of claim 7, wherein if it is determined that the network node is to send a password to the second node, then the at least one circuit operates to:
transmit a third message to the second node communicating the password to the second node; and
transmit a fourth message indicating a slot in which the second node is to acknowledge receipt of the third message.

14. The network node of claim 7, wherein if it is determined that the second node is to send a password to the first node, then the at least one circuit operates to:
transmit a third message to the second node indicating a slot in which the second node is to send a fourth message communicating the password to the network node; and
receive the fourth message communicating the password from the second node.

15. The network node of claim 14, wherein the third message specifies that the fourth message be of a particular type.

16. The network node of claim 7, wherein the first node is a network coordinator node.

17. A network node comprising:
at least one circuit operable to, at least:
receive a first message from a second node comprising information that indicates protected setup has been triggered;
receive a second message from the second node indicating a slot in which the network node is to acknowledge receipt of the first message;
transmit a message to the second node at the indicated slot acknowledging receipt of the first message by the network node;
determine whether to send a password to the second node or whether to receive a password from the second node;
if it is determined to send a password to the second node, then send a password of the network node to the second node; and
if it is determined to receive a password from the second node, then receive a password of the second node from the second node.

18. The network node of claim 17, wherein the second message specifies a particular type of acknowledgement message to be transmitted by the network node in the indicated slot.

19. The network node of claim 17, wherein the first message is a Discovery Response message comprising an information element indicating that protected setup has been triggered.

20. The network node of claim 17, wherein if it is determined that the network node is going to send a password to the second node, then the at least one circuit operates to:
receive a third message from the second node indicating a slot in which the network node is to send a fourth message communicating the password to the second node; and
transmit the fourth message in the slot indicated by the third message communicating the password to the second node.