# US 2016/0366103 A1 · Method and apparatus for encoding security status information > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0366103 A1 - Document ID: US20160366103A1 - Status: Published application - Kind: A1 - Application number: 14/470,364 - Filed: 2014-08-27 - Published: 2016-12-15 - Earliest claimed: 2002-12-04 - Assignees: Certicom Corp. - Applicants: Certicom Corp. - Inventors: Marinus Struik - Web page: https://patentgrep.com/patent/US20160366103A1 ## CPC - H04L 63/0428: {wherein the data content is protected, e.g. by encrypting or encapsulating the payload} - H04L 1/1803: Stop-and-wait protocols - H04L 1/1812: Hybrid protocols; Hybrid automatic repeat request [HARQ] - H04L 1/1867: Arrangements specially adapted for the transmitter end - H04L 47/34: ensuring sequence integrity, e.g. using sequence numbers - H04L 63/0435: {wherein the sending and receiving network entities apply symmetric encryption, i.e. same key used for encryption and decryption (cryptographic mechanisms or cryptographic arrangements for symmetric key encryption H04L9/06)} - H04L 63/06: {for supporting key management in a packet data network (cryptographic mechanisms or cryptographic arrangements for key management H04L9/08)} - H04L 67/04: specially adapted for terminals or networks with limited capabilities; specially adapted for terminal portability - H04L 67/12: specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks - H04W 12/02: Protecting privacy or anonymity, e.g. protecting personally identifiable information [PII] - H04W 12/033: of the user plane, e.g. user's traffic - H04W 12/04: Key management, e.g. using generic bootstrapping architecture [GBA] - H04W 56/0015: {one node acting as a reference for the others} - H04L 69/329: in the application layer [OSI layer 7] - H04L 2209/80: Wireless - H04W 4/12: Messaging; Mailboxes; Announcements - H04W 24/00: Supervisory, monitoring or testing arrangements - H04W 28/04: Error control - H04W 28/06: Optimizing {the usage of the radio link}, e.g. header compression, information sizing {, discarding information (system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365)} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A method of transmitting messages from a sender to a recipient over a wireless channel, the messages including a sequence counter and a frame counter. The method comprises establishing initial values of the sequence counter and the frame counter at the sender. Initial values of the frame counter and the sequence counter are provided to the recipient. The sender sends compressed messages including the value of the sequence counter and not the frame counter and monitors for an acknowledgement of receipt by the recipient. When no acknowledgment is received, the sender sends uncompressed messages until an acknowledgement of receipt is received from the recipient. The sequence counter is incremented and the next value of the frame counter is established as the integer next larger than previous value of the frame counter which is congruent to the sequence counter modulo 256. ## Claims ### Claim at position 1 1-2. (canceled) ### Claim 3 A wireless device comprising: one or more processors configured to: store a local value of a frame counter; receive a second message after a first message over a wireless network, the second message including a sequence counter value identifying the second message relative to other messages in a stream of messages and data encrypted by a correspondent using a secret key; determine a new value of the frame counter from the local value of the frame counter and the sequence counter value in the second message; and decrypt the second message based on the new value of the frame counter. ### Claim 4 (depends on 3) The wireless device of claim 3, wherein the new value of the frame counter is an integer that is next larger than the local value of the frame counter and congruent to the sequence counter value modulo a specified integer. ### Claim 5 (depends on 3) The wireless device of claim 3, wherein the sequence value comprises a compressed representation of the new value of the frame counter. ### Claim 6 (depends on 3) The wireless device of claim 3, wherein the one or more processors are further configured to send the correspondent an acknowledgement message in response to receiving the second message unless an error flag indicates a loss of synchronization with the recipient. ### Claim 7 (depends on 6) The wireless device of claim 6, wherein the acknowledgment message includes the sequence counter value. ### Claim 8 (depends on 3) The wireless device of claim 3, the one or more processors further operable to: detect a decryption error based on a loss of synchronization of the frame counter with the correspondent; and set an error flag based on the detecting of the decryption error, the error flag indicating the loss of synchronization of the frame counter with the correspondent. ### Claim 9 (depends on 8) The wireless device of claim 8, the one or more processors further operable to: determine that the recipient has failed to send an acknowledgment indicating successful decryption of the message; and in response to the determining, send the new value of the frame counter to the recipient to synchronize the frame counter with the recipient. ### Claim 10 (depends on 9) The wireless device of claim 9, the one or more processors further operable to remove the error flag upon receiving from the correspondent a third message that includes a current value of the frame counter. ### Claim 11 A wireless device comprising: one or more processors configured to: store a local value of a frame counter of a recipient; compute a new value of the frame counter from the local value of the recipient and a sequence counter value identifying a second message relative to other messages in a stream of messages; encrypt data in the second message using a secret key and the new value of the frame counter; and send the second message to the recipient over a wireless network, the second message including the sequence counter value and the encrypted data. ### Claim 12 (depends on 11) The wireless device of claim 11, wherein the one or more processors are configured to compute the new value of the frame counter such that the new value of the frame counter is an integer that is next larger than the local value of the frame counter or the recipient and congruent to the sequence counter value modulo a specified integer. ### Claim 13 (depends on 11) The wireless device of claim 11, wherein the sequence value comprises a compressed representation of the new value of the frame counter. ### Claim 14 (depends on 11) The wireless device of claim 11, wherein the one or more processors are further configured to receive an acknowledgement message from the recipient. ### Claim 15 (depends on 14) The wireless device of claim 14, wherein the acknowledgment message includes the sequence counter value. ### Claim 16 (depends on 11) The wireless device of claim 11, wherein sending the new value of the frame counter to the recipient resynchronizes the frame value with the recipient. ### Claim 17 A method, comprising: storing a local value of a frame counter; receiving a second message after a first message over a wireless network, the second message including a sequence counter value identifying the second message relative to other messages in a stream of messages and data encrypted by a correspondent using a secret key; determining a new value of the frame counter from the local value of the frame counter and the sequence counter value in the second message; and decrypting the second message based on the new value of the frame counter. ### Claim 18 A non-transitory computer readable medium storing instructions to cause a processor to perform operations comprising: storing a local value of a frame counter; receiving a second message after a first message over a wireless network, the second message including a sequence counter value identifying the second message relative to other messages in a stream of messages and data encrypted by a correspondent using a secret key; determining a new value of the frame counter from the local value of the frame counter and the sequence counter value in the second message; and decrypting the second message based on the new value of the frame counter. ### Claim 19 A method, comprising: storing a local value of a frame counter of a recipient; computing a new value of the frame counter from the local value of the recipient and a sequence counter value identifying a second message relative to other messages in a stream of messages; encrypting data in the second message using a secret key and the new value of the frame counter; and sending the second message to the recipient over a wireless network, the second message including the sequence counter value and the encrypted data. ### Claim 20 A non-transitory computer readable medium storing instructions to cause a processor to perform operations comprising: storing a local value of a frame counter of a recipient; computing a new value of the frame counter from the local value of the recipient and a sequence counter value identifying a second message relative to other messages in a stream of messages; encrypting data in the second message using a secret key and the new value of the frame counter; and sending the second message to the recipient over a wireless network, the second message including the sequence counter value and the encrypted data.