Patent Publication Number: US-11641400-B2

Title: Method and apparatus for secure passive wireless communication with Bluetooth vitals devices

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/865,990, filed Jan. 9, 2018. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to secure communication systems and methods and more particularly to a secure wireless communication network coupling Bluetooth Low Energy (BLE) and other medical devices via gateway(s) to any endpoint including but not limited to the Internet, Electronic Health Records (EHR), data management and various servers, allowing for access by services and users of the system. 
     BACKGROUND 
     Generally speaking, so called “Smart” vital signal medical devices have become ubiquitous and readily available, contained in such products as consumer smart-scales, smart blood pressure meters, smart glucose meters, and others. The data produced by such devices is useful in a number of healthcare and wellness environments. However, the wireless technology and protocols used in such readily available consumer equipment makes long range transmission difficult for a number of reasons. The claimed invention described herein offers a more robust apparatus and method for performing this task. 
     Typically, vitals devices are equipped with integrated Bluetooth Low Energy (BLE) radios. BLE itself, a relatively short range protocol, requires some form of a gateway device to allow long range transmission of the data to remote web services or Electronic Health Record (EHR) systems. For the most common instances, a user&#39;s smartphone is expected to fulfill this role. Further details can be found in the Bluetooth Core Specification version 4.0 and later. 
     One drawback of using a cellular phone for this role is that many devices require the phone to be in close proximity to the device when the measurement is taken. Additionally, a specific application related to the smart device often must be installed and configured by the user of the system. This requires multiple specific application software sets to be installed on the phone of a single user if they have multiple smart devices. Additionally, the application software may need to be performed in the foreground, meaning that the telephone requires a user&#39;s interaction prior to and during the measurement process. This entails an additional burden upon the patient and consumer of such data. 
     Another drawback associated with using a cellular phone is that BLE connections themselves are often unreliable on complex platforms, such as modern smartphones, which have many hidden software activities being simultaneously performed. Packets over a BLE link can be reordered or coalesced many times from connection to connection, in essence, by changing the over-the-air persona of the smartphone, further exposing transmission errors and precipitating the occurrence of reception errors that may be present in the smart device&#39;s firmware. 
     Another common difficulty encountered with connecting a multi-protocol gateway device communicating with a BLE device to a longer range wireless network is the timing-sensitive nature of the BLE packets. Bluetooth Low Energy (BLE) divides the 2.4 Ghz industrial, scientific and medical devices (ISM) band into 40 channels of 2 Mhz in width. Although not conforming to a linear map between frequency space and channel id number, the protocol makes an effort to spread communications over the entire width of the ISM band in order to probabilistically avoid interference from other BLE connections as well as WiFi/802.11x or any other communications system making use of the band. Attempts to create a form of a dedicated communication channel tunnel where a remote service makes requests to send and receive BLE packets may again encounter limitations in the smart devices where both elements expect events to take place in narrow intervals and cannot tolerate jitter or delay in the timing. 
     An additional difficulty associated with producing such a gateway is that some long-range communications technologies may have unacceptably long latencies and low bit rates. Even though some smart devices may measure quantities as simple as a person&#39;s weight, the total data volume of data that needs to be transferred can result in the tens of thousands of bytes. Reducing the requisite volume of data is a desired intention. 
     BLE smart devices utilize a security model that involves a “pairing” process whereby the remote device and the “host” device perform a key exchange that allows for secure communication. Some methods of key-exchanges require a user interface on the “host” device to enter a secure entry of a secret code, typically known as a “PIN”. This is nearly impossible on a gateway device that contains no user interface. Even in cases where a user interface is neither available or not required, the process appears to be too complicated for many users, with many users reporting difficulty in pairing their devices. Additionally, it does not in principle, make sense that users themselves must perform the key exchange since it should be possible to distribute keys between the device and gateway prior to device distribution in order to achieve the same, or an even higher level, of security. The security function is expressed by: E.sub.x(y), which is the AES-128 standard encryption of plaintext y by key x as defined in FIPS-197. 
     Another limitation associated with BLE gateways is their relatively short reception range, which may not allow a single gateway to achieve ideal coverage for an entire building. The use of multiple gateways can incur significant cost because of the need to use multiple long range wireless transmitters. Additionally, smart home devices that are “paired” with one gateway, may begin to loose their connectivity function if they are moved ever so slightly to connect to a different gateway in the same building. 
     Yet another common problem is that it may not be necessary to limit the instances in which data can be collected from a smart device to those instances where a specific gateway is in proximity of said device since the end point for the data is actually an internet service. 
     SUMMARY OF THE INVENTION 
     In its most general aspect, the present invention includes a BLE chip-set, containing a multitude of processors, communication radios, memory for the storage of data, and software programs for controlling the communications taking place over the radios. Antennas, and appropriate electronic circuits may also be contained so as to connect the various communications components and processors. The ability to select specific software programs for loading, depending on which smart home devices the gateway should be connecting to, affords maximal selectivity in addressing remote devices. 
     In another aspect, a secure communication device is provided to operate in a networked multi-protocol system that may communicate with smart devices. The communication device may include a Bluetooth communication network controller, having a processor and transmitter, said network controller configured to maintain consistent over-the-air profile from the smart devices perspective and receive information from the smart devices and transmit said information from the smart devices for use by stakeholders over a communication channel. 
     The device gateway uses an address in a random privately resolvable space by exchanging keys over a publicly offered communication channel wherein the same address resolution key is re-used to generate an offered medial access control address (MAC address) to further afford the exchange of more secure bonding keys that are transparently copied between device gateways, said key computation more specifically contained in a variation of a known sequence. 
     The Bluetooth controller transceiver is interoperable with a plurality of smart devices, wherein said plurality of smart devices are BLE configured medical vital signs devices 
     The secure communication device further includes components selected from the group consisting of a LoRa (“Long Range”, a spread spectrum modulation technique derived from chirp spread spectrum (CSS) technology) transceiver element wherein said LoRa transceiver is further operable on a separate and concurrent radio channel simultaneously with said other communication channels; a WiFi transceiver element wherein said WiFi transceiver is further operable on a separate and concurrent radio channel simultaneously with said communication channels; a cellular transceiver element wherein said cellular transceiver is further operable on a separate and concurrent radio channel simultaneously with said communication channels; an Ethernet transceiver element wherein said Ethernet transceiver is further operable on a separate and concurrent radio channel simultaneously with the communication channels; a direct IP transceiver element wherein said direct IP transceiver is further operable on a separate and concurrent radio channel simultaneously with communication channels; and combinations thereof. 
     The secure communication device wherein said device is a gateway and includes at least two a gateways forming a mesh network configure to maximize communications with said smart devices. The number of gateways is dependent upon the number of smart devices in use and what is necessary to allow efficient communications between the smart devices which can be vitals devices and the gateways. 
     The secure communication device may contain software running on the device, said software being reformatted through a series of pre and post processors to output a readily understood object format; processing said object format through a shared libraries printer to further optimize said object code for execution on a stack-oriented virtual machine (VM) architecture. 
     The secure communication device may contain software running on the device with an executable software image being optimized in order to reduce the bandwidth required for transport over the network by creating a more lightweight version of the binary image by containing it in a more size and load time efficient format. 
     The secure communication device includes specific software programs which are selectively loaded depending on which smart home devices a gateway should be interconnected to by detecting devices expected to be in range. Multiple drivers are downloaded in unique combinations specific to vitals devices known to be in range of said gateways. 
     The secure communication device&#39;s Bluetooth controller receives identification packets from Personal Digital Assistance devices (PDAs) and wearable devices wherein the location of the PDAs and wearables in relation to the smart devices is correlated to determine the identity of the user of the smart device. 
     There are other inventive matters including systems, methods and software that are set forth more fully in the detailed description, which matters will be the subject of further claim sets. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, illustrate exemplary embodiments of the invention, and together with all of the parts of this application, serve to explain the features of the invention. 
         FIG.  1    illustrates the functional components of an embodiment of a wireless communication system. 
         FIG.  2    illustrates the internal components of a device gateway according to a preferred embodiment of the present invention. 
         FIG.  3    illustrates a perspective view of a wireless gateway device according to an embodiment of the present invention. 
         FIG.  4    is a block diagram illustrating the flows of data during management operations according to an embodiment of the present invention. 
         FIG.  5    is a block diagram illustrating the event listening state machine according to an embodiment of the present invention. 
         FIG.  6    is a block diagram illustrating the process of converting commonly well-understood human readable code to a machine executable code in accordance with a proscribed embodiment of the present invention. 
         FIG.  7    illustrates a possible human interface enabled by an embodiment of the present invention. 
         FIG.  8    illustrates the initialization process flow at start-up. 
         FIG.  9    illustrates the salient highlights of the protocol exchange that takes place in establishing a connection with a newly discovered BLE device being introduced and incorporated into a secure connection BLE environment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Many smart devices are now readily available in consumer markets. For example: body weight scales, blood-pressure monitors, glucometers, thermometers, pulse oximeters and fitness trackers are a subset of the myriad of medical monitoring devices available to consumers and healthcare professionals. Manufacturers consistently focus on providing a more ideal user experience involving the user&#39;s phone and either a single medical smart vitals device or a number of medical smart vitals devices. Communication standards, so far, have been a low priority, and in many cases, manufacturers have undertaken efforts specifically aimed at limiting interoperability. From a healthcare perspective, this has limited the utility of what is clearly a preferred digital generated healthcare data format, since the smart home devices already have the capability to transmit data wirelessly. The various embodiments set forth herein create a form of wireless wide area network (WWAN) that is capable of communicating with this plethora of smart devices using an extension of the BLE standard. 
     As an example, an individual may own various smart home devices in their home, such as a body-weight scale or a blood pressure monitor, as well as use several more portable devices, such as a glucometer and a pulse oximeter. All of these smart home devices, while having a need to navigate a diverse set of higher level protocols, would make use of the underlying BLE protocol. Although these devices are all designed to make use of a personal area network (PAN), a preferred embodiment using a wireless system set forth herein allows them to work as though BLE is a wide area network (WAN) protocol. 
     By installing one or many of the device gateways  110  to communicate with a vitals device  130 , the data flow system in  FIG.  1    is enabled. Vitals devices  130  may be any one of the devices described above, including scales to measure weight, glucose monitors to measure blood sugar levels, blood pressure measuring devices, pulse oximeters, or other monitoring and data producing devices. The measurements generated by these vital monitoring devices  130  are “scraped-off” to reduce the necessary data transfer volume, thus enabling them to be monitored by users of the system, including patients and physicians, patient care managers and other interested parties. The process of “scraping” involves eliminating ancillary data contained in a vitals device measurement data set not essential to the transfer of core data, such as contained in the layered packet transport protocol overhead. Gateways  110  are set up to form a mesh network in order to cover the entire facility housing the vitals devices  130 . A particular gateway  110  determines which vitals devices it will monitor in view of which gateway receives the strongest signal from the particular vitals device  130 . These measurements may be sent by the gateways  110  via transmission means  140  over the Internet  150  for further processing, storage and dissemination. The gateways  110  that form a mesh network to cover the entire facility  105  may vary in their contained components as is necessary to most efficiently form a system that ties into transmission means  140 . For example, selected gateways  110  may contain some or combinations of the radios and communication nodes used to transmit the data to Internet  150  as more fully described in the ensuing detailed description. The transmission means  140  may include transmissions via LoRaWAN referred to as “LoRa”, radio networks  141 , cellular radio networks  142 , WiFi networks  143  and/or direct IP networks  144  that may include a cable modem or any components (not shown), such as an ethernet connection, enabling direct Internet Protocol (IP) transmissions. The transmission means that 140 may in turn distribute the vitals measurements over the Internet for further distribution. One embodiment incorporates the ability to incorporate wearable devices, mobile phones, PDAs and/or other devices, which are generally designated as devices  135 . In yet a further embodiment, devices  135  may be utilized to identify the particular user or patient utilizing a vitals devices  130 . Prior to a gateway device connection being formed, devices broadcast amongst themselves identifying data in an attempt to solicit incoming connections. All gateways in proximity are able to receive these identification packets and correlate the ID&#39;s with known devices. The occurrences of the witness events can then be transmitted to a web service along with the associated received signal strength indicator of said packets. The service can use this information to coarsely constrain the relative location of identified devices at various moments in time. If a vitals measurement is then taken, the relative position of all devices in the environment can be further queried for that instant. This data may be useful to ascertain the identity of the person that is using the vitals measurement device, or more specifically, used to differentiate between a small number of people that may have used the measuring device, such as the residents of a home. 
     Internet  150  may be used to distribute vitals information to any number of users of the system, data management services  170 , or electronic health records (EHR)  160  that may in turn be transmitted or accessed by, for example, physicians  161  and/or patients  162 . The vitals information or data may be distributed via Internet  150  to, for example, care management  180 , patients  185 , and/or personalized data services  190 . 
     Internet  150  may also distribute such vitals information and/or data to data management services  170  capable of long term storage for both archival and analytical purposes. 
     Data may then be processed by the remote data management service  170  in such a way as to allow for direct insertion into an EHR  160 . It may also be analyzed for anomalies or critical situations where manual intervention may be necessary to ensure integrity of such data and information.  FIG.  7    illustrates a type of user interface that may be enabled by the present invention, with specific regard to displaying long term vitals measurement data and historical trends. 
     With reference to  FIG.  1    and a more general wireless communication system  100 , the gateway devices  110  may be installed into a mesh network in facility  105  as needed to ensure communication between the monitoring equipment such as vital devices  130  and at least one gateway device  110 . The vital devices  130  are generally Bluetooth devices, more particularly BLE devices. Depending on the number and location of the vitals devices  130 , gateway devices  110  can be installed and positioned in the user&#39;s facility  105  to maximize communication with vitals devices  130  to enable the secure communication of data and information to the gateway devices  110 . The gateway devices  110  may be equipped with various radios and communication components necessary to ensure communication over every supported communication network described in  FIG.  1   . 
     As seen in  FIG.  2   , a device gateway  110  may contain a BLE module  220  including or coupled to a real-time processor; in a preferred embodiment the BLE module  220  may be a Bluetooth radio controller. The BLE module  220  also may include a Bluetooth antenna  227 , or a connection to a 2.4 Ghz antenna  227 . Module  250  may be a single board computer that may contain integrated flash memory, dynamic random access memory (DRAM) and microprocessor (MPU). In a preferred embodiment, module  250  may be a more powerful single board computer and include a WiFi transceiver with a connection to a 2.4 Ghz antenna  257 . The BLE module  220  is responsible for maintaining the consistent over-the-air profile of the gateway device from the perspective of a smart home device  130 . This is achieved by using low-level packet send/receive functions without making use of functions that may be capable of introducing random amounts of buffering and/or the reordering of packets. BLE module  220  also facilitates key exchanges between gateways  110  and vitals devices  130 , establishing the mesh network of multiple gateways  110 , scanning various vitals devices  130  to determine events such as new readings and/or measurements obtained from the vitals devices  130 , enabling communication with vitals devices by supplying the correct and/or updated drivers for such devices  130 , and creating secure connections to transfer such readings and measurements from devices  130  and the software running on the BLE Module  220 . The BLE Module  220  can also communicate with devices that can function as a personal assistant hub including, but not limited to, devices that can run Google Home and Amazon Alexa; physical embodiments of device may be offered on Alexa, Google Home, Apple TV or third party system offering a wireless radio capability; these functions are more fully described hereinafter. All elements described in this paragraph are contained on circuit card assembly  201 . 
     The gateway  110  may also contain a LoRa module  235  which may have a LoRa compatible transceiver and associated protocol stack running on either an included processing unit or another processor embedded into the gateway. LoRa module  235  may include a connection to a 915 MHz antenna  237 . In a preferred embodiment, module  250  is programmed to control LoRa module  235  as well as to control any link between the BLE module  220  and the LoRa module  235 . 
     The gateway  110  may contain a cellular radio  245  as well as a higher performance CPU in the form of a embedded computer  250  to manage this high bandwidth connection. This higher performance computer  250  is capable of running a standard operating system such as Linux, while simultaneously maintaining a secure channel to a remote server using a virtual private network (VPN) or other encrypted transport channel; remote updates to the software for all processors are possible over such a link. By a preferred embodiment utilizing a mini PCIE card  240  for the cellular radio  245 , further in combination with computer  250 , may allow for economies of scale to be achieved while providing a high performance computer  250  capable of being programmed as necessary to achieve various functionalities. In a preferred embodiment, a subscriber identity module (SIM) card  246 , which is attached via a mini PCIE card  240 , to enable authorized access to cellular networks. In a preferred embodiment a MicroSD  251  or Embedded MultiMediaCard (eMMC)  251  is attached to this higher performance computer  250  in order to provide bulk storage for software as well as long term logs of measurements taken and other logs useful for debugging. 
     A preferred embodiment for gateway  110  includes a BLE module that incorporates BLE module  220 , a LoRa radio  235 , a cellular radio incorporated into PCIE card  245  that further includes both primary antenna  247  and a diversity antenna  249 , and a computer module  250 . The foregoing components are connected via a serial connection  261 , and Universal Serial Bus (USB)  260  and may be powered by a power supply unit (PSU)  210 , which may be plugged into a 110V/220V wall outlet and constructed to convert alternating current to direct current that supplies 5 volts of power to gateway unit  110  and its components. Gateway  110  may solely utilize the BLE module  220  or combinations of the above identified components and radios. Gateway  110  must provide at least one link between bluetooth and connection methods  140 . Since nearby Gateways  110  may provide such a connection, a given gateway may need only contain BLE module  220 , omitting the LoRa Radio  235 , MPU module  250  and cellular module  245 , so long as it is known that at least one gateway within the mesh can provide a service  140 . Relatedly, an installed Gateway  110  meant to provide a service  140 , may need only contain BLE module  220  along with LoRa module  235 , if LoRa is the chosen transport. MPU module  250  can be included to give WiFi support, along with a cellular module  245  for cellular access. 
     With reference to  FIG.  3   , an embodiment is shown regarding the structure of gateway  110 , showing that PSU  210  slidably and removably engages into slot connectors to make electrical contact with gateway connector contacts, preferably using a standard USB connector  320  permanently affixed to mating assembly  310 . This design enables the replacement of PSU  210  should it fail or should different requirements be demanded by the components and/or radios of gateway  110 . PSU  210  may be purchased or designed to be in accordance with various electrical and safety codes as well as serve as a power limiting device to ensure the safety of other components within gateway  110 . Housing  315  is used to enclose the sensitive electronics from the environment. 
       FIG.  8    illustrates the initialization process that occurs within a gateway  110  when a gateway is first powered-on. The process begins with the introduction of power as shown in  FIG.  8    as the initialization element labelled “Start”  800 . Once all the power-on ramps-up and the down-converting power sequencing has completed the gateway proceeds to identify and establish all available communication channels. The gateway&#39;s processor first establishes a communication path using the Bluetooth channel per  810  and  811  resulting in  812 . The gateway systematically queries all other available communication pathways by checking for the availability of a LoRa, a WiFi, a cellular, and a direct channel using direct IP connectivity. The gateway determines the availability of all potentially available pathways  820  using the logical inferences contained in  821 ,  822 ,  823  and  824 . Based on this query stage,  824 , may invoke additional computational resources as determined by  825  by invoking  826  as needed. Once all the additional channels are established using  827 , the gateway enters a quiescent mode following  828  wherein the gateway  110  monitors all identified channels for maintaining connectivity on every possible communication path using  830 . In the event that a channel has been detected as not available to the system monitoring subsystem  830  begins the process of re-identifying and re-establishing available paths by reverting to stage  800 . The gateway hardware is typically pre-built to contain sufficient resources to contain the processing power necessary to maintain a maximal multi-protocol communication system. 
     At system initialization time, the gateway  110  performs a process of identifying all possible available communication channels; this flow is illustrated in  FIG.  8   . This process entails establishing a BLE channel first, and from there seeking any and all possible additional offered communication channels, be they offered via LoRa, WiFi, cellular, or Ethernet or other protocols allowing connectivity such as direct IP connectivity. In the event that multiple channels are available the gateway will make a determination if more computational devices are required to best match with the requisite requirements. Resources may be predetermined at build time to minimize customer concerns. 
     The three affordances of the implementation of security in BLE devices are: authentication, confidentiality and authorization. Many BLE slave devices may refuse to transmit vitals data if the link encryption protocol is not enabled. Additionally, most devices require some sort of mechanical user input, such as pushing a specific button in order to enable encryption with a new peer.  FIG.  4   , describes a showing how the keys generated/exchanged during the bonding process may be sent to the management services (“MS”)  470  in encrypted form using a secret key known only by gateway  110  and MS  470 . If, at a later time, a different gateway  110  in environment  105  makes a connection to vitals device  130  for which it does not know the bonding keys in use, gateway  110  may then request a copy of the keys from MS  470 , by using the shared secret known only to the particular instance of gateway  110 . 
     With reference to  FIG.  4   , either a user  410  or their health care provider  420  may elect to provision a new vitals device  130 . During this process, a request to provision the device is made via inputting information including, for example, the User ID and the identification of the vitals device over internet  450  in communication with management services (“MS”)  470 . MS  470  may access information from, for example, a database server  471 ; this database may be updated from time to time and, for example, when a new device is provisioned, the software for which then attempts to transfer the new data to the relevant gateways on a best efforts basis, via links to gateways  490 —these provisioning packets contain the driver code and device keys, if relevant, to “scrape” the configured target vitals device for storage and use by network  100 . Alternatively, MS  470  may access information from a cloud service  430  or otherwise. This request can be initiated by any software or website  460  with sufficient privileges to make the request. Website  460  is home to an EHR database and may be the front end that monitors the vitals or enables initiating provisioning for a new vitals device as is more fully described hereinafter and shown in  FIG.  7   . The database (DB)  471  may contain the MAC addresses for the vitals devices  130  and gateways  110 , relevant links and code to extract vitals data. DB  471  may also contain a unique encrypted patient ID, where the vitals devices  130  and gateways  110  are housed together with owners of these devices and case managers for these devices. DB  471  may additional contain physician or other interested user information and link this information to the users of the vitals devices. 
     Once the provisioning request is extended, an attempt is made to locate the corresponding gateways in proximity to the specific user, then the provision is stored in the database. Upon location of corresponding gateways  110 , MS  470  forwards the requisite information to the correct gateway via links  490 . 
     The real-time processor associated with the BLE module  220  is responsible for executing smart device specific drivers during every connection. These drivers may be distributed in a binary device-agnostic form and in a preferred embodiment, a reformatted variant of the WebAssembly binary format. These drivers are relatively small and can be transferred even over low-bandwidth links such as LoRa. Multiple drivers can be simultaneously loaded on BLE module  220  of gateway  110  in unique combinations specific to the gateway  110 , in particular by making use of knowledge of which devices  130 ,  135  are expected to be in range. 
       FIG.  6    illustrates how the software that executes on the gateway  110  is first reformatted by a series of pre and post processors. The source code is first run through a compiler  601  to output a readily understood object format. The object code is then processed by a shared libraries printer  602  that optimizes the object code for execution on a stack-oriented virtual machine (VM) architecture. In order to reduce the bandwidth required for transport over certain networks, the reformatter  603  optimizes the executable image into a more, size and load time, efficient format; this format is inter-operable among the supported devices. 
       FIG.  5    illustrates the steps used in the gateway&#39;s connection and provisioning process. Element  509  shows the first step wherein the gateway terminal server waits for events, when an event is detected element  510  determines if the recognized event corresponds to a provisioning request or to a connection request. Element  511  determines if the event is associated with a new provisioning request passing this information to element  512  which determines for how many gateways a provisioning requests is required; for each gateway in a new provisioning request the flow returns back to element  509  where the previously described flow continues until all provisioning requests first detected are exhausted. Once element  513  is completed, it will determine if a connection already exists, if not, then element  514  saves the provisioning request(s) to a queue of pending updates; if determined that an positive affirmation response such as a “yes”, is expected, then element  515  sends an update notification payload to the requesting gateway and then returns to element  513  until all request are exhausted after which the procedure returns to element  509  to await receipt of new events. In the case that element  510  had determined that a connection request was detected element  520  will confirm that the connection request is valid and element  521  will check for pending payload packets to be sent by invoking element  515  until the entire series of requests are transmitted to the requesting gateway. Upon completion the process returns to element  509  to await new provisioning and connection requests. 
     Below is the description of the events that occur in a typical Bluetooth Low-Energy connection flow. Further details can be found in the Bluetooth Core Specification version 4.0 and later. Specific details of the physical layer such as modulation, whitening and the various polynomials used are omitted for brevity. The specific meaning of bits, the frequencies used and the timing of the events in the channel is also left to the reader. Special attention must be paid to the padding of fields during concatenation of the cryptographic primitives. All messages can lead to a variety of error notification and subsequent handling conditions, none of which are covered here. 
       FIG.  9    showcases the events comprising the typical connection between a bluetooth low-energy vitals device  910  and a master device such as a gateway  920 . The vitals device initially advertises by sending a Adv Channel PDU message  901  on logical channel  37 ,  38  or  39 . Once the gateway receives an ADV_IND message, it checks to see if the vitals device is provisioned. If additional information needed to information is determine provisioning, the gateway  920  sends a SCAN_REQ message  902  to which the vitals device  910  responds by sending SCAN_RSP message  903 . If the gateway  920  acknowledges this as a valid request, it will respond with a CONNECTION_IND response message. At this point, a new Access Address is randomly generated by the gateway  920 . Access Address is a connection unique identifier generated according to specified rules. 
     The MAC address is critical to the identification of peers while establishing and securing the link. A mapping between device MAC address and a randomly generated Access Address is created when a connection is initiated. The features of the security extensions offered in the claimed invention improve limitations contained in the standard BLE security protocol. Since the BLE protocol exposes the MAC addresses of both the master and slave during a connection process, provisions to the protocol were made in which devices could remain anonymous. This is implemented by creating MAC addresses, which are periodically updated. 
     The device gateway  110  makes use of an address in the random private resolvable space in the BLE specification. This is used in bonded devices and requires the Identity Resolving Key (IRK) to be shared during Phase Three of the pairing procedure as defined in the Bluetooth Core Specification version 4.1. In usual practice, such addresses are made to change periodically based on a timer or other method whereas, in the present invention, such addresses may remain static. Each gateway  110  in environment  105 , uses a different such address, all generated from this same IRK, where IRK is any suitable 128-bit key material. This allows the bonding keys to be transparently copied between trusted device gateways  110  in a manner that will be more fully described hereinafter. This implies there exists a multitude of MAC addresses that a peer will associate with correct link keys. The resulting scheme easily allows inter-gateway connections to be created for the purpose of creating a mesh network.