# US 8,787,575 B2 · Method and apparatus for propagating encryption keys between wireless communication devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,787,575 B2 - Document ID: US8787575B2 - Status: Granted - Kind: B2 - Application number: 12/675,784 - Filed: 2007-08-31 - Published: 2010-12-02 - Granted: 2014-07-22 - Earliest claimed: 2007-08-31 - Assignees: France Brevets - Applicants: Miika Laaksonen; Hannu Ensio Laine; Jan-Erik Ekberg - Inventors: Miika Laaksonen; Hannu Ensio Laine; Jan-Erik Ekberg - Web page: https://patentgrep.com/patent/US8787575B2 ## CPC - H04W 12/04: Key management, e.g. using generic bootstrapping architecture [GBA] - H04L 9/3228: {One-time or temporary data, i.e. information which is sent for every authentication or authorization, e.g. one-time-password, one-time-token or one-time-key} - H04L 9/3242: {involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC} - H04L 63/062: {for key distribution, e.g. centrally by trusted party (cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819)} - H04W 12/50: Secure pairing of devices - H04L 63/104: {Grouping of entities} - H04L 2209/805: Lightweight hardware, e.g. radio-frequency identification [RFID] or sensor - H04W 12/02: Protecting privacy or anonymity, e.g. protecting personally identifiable information [PII] - H04W 84/18: Self-organising networks, e.g. ad-hoc networks or sensor networks - H04W 88/06: adapted for operation in multiple networks {or having at least two operational modes}, e.g. multi-mode terminals - H04W 92/18: between terminal devices - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A system for propagating encryption key information between wireless communication devices without the requirement of pairing each and every device. A wireless communication device may be paired with at least one device in a group of devices. When a secure link is established between these devices, a determination may be made as to whether encryption key information should be passed from one device to another. The additional encryption key information may allow a wireless communication device to create a secure link with other devices without having to first establish a trusted relationship (e.g., go through a pairing process) with the other devices. ## Claims ### Claim 1 A method, comprising: establishing a wireless link between an encountered device and a first device; determining whether a trusted relationship exists between the first device and the encountered device by checking whether an encryption key associated with the encountered device is stored within the first device; if the encountered device is determined to be a trusted device, establishing a secure link between the first device and the trusted device using the stored encryption key; and receiving, in the first device, encryption key information from the trusted device via said secure link for establishing a secure link between the first device and a target device, wherein the encryption key information comprises another encryption key and target device information identifying the target device associated with the other encryption key. ### Claim 2 (depends on 1) The method according to claim 1, further comprising providing information to the trusted device before receiving the encryption key information from the trusted device. ### Claim 3 (depends on 1) The method according to claim 1, wherein the received encryption key information further includes information identifying the trusted device as source for the information. ### Claim 4 (depends on 1) The method according to claim 1, further comprising establishing a secure link between the first device and the target device using the received encryption key information. ### Claim 5 A method, comprising: establishing a wireless link between an encountered device and a second device; determining whether a trusted relationship exists between the second device and the encountered device by checking whether an encryption key associated with the encountered device is stored within the second device; if the encountered device is determined to be a trusted device, establishing a secure link between the second device and the trusted device using the stored encryption key; determining if encryption key information for establishing a secure link between the trusted device and a target device is to be transmitted to the trusted device via the secure link, wherein the encryption key information comprises another encryption key and target device information identifying the target device associated with the other encryption key, wherein said another encryption key is also for establishing a trusted relationship between the second device and the target device; and if it is determined that the encryption key information for establishing a secure link between the trusted device and the target device is to be transmitted, transmitting the encryption key information to the trusted device. ### Claim 6 (depends on 5) The method according to claim 5, wherein the encryption key information for establishing a secure link with the target device was received through a trusted relationship with the target device. ### Claim 7 (depends on 5) The method according to claim 5, wherein determining if encryption key information for establishing a secure link between the trusted device and the target device is to be transmitted to the trusted device is based on information received from the trusted device. ### Claim 8 (depends on 5) The method according to claim 5, wherein the encryption key information further includes information identifying the second device as source for the information. ### Claim 9 A computer program product comprising a non-transitory computer usable medium having computer readable program code embodied in said medium, comprising: a computer-readable program code configured to establish a wireless link between an encountered device and a first device; a computer-readable program code configured to determine whether a trusted relationship exists between the first device and the encountered device by checking whether an encryption key associated with the encountered device is stored within the first device; a computer-readable program code configured to, if the encountered device is determined to be a trusted device, establish a secure link between the first device and the trusted device using the stored encryption key; and a computer-readable program code configured to receive, in the first device, encryption key information via said secure link from the trusted device for establishing a secure link between the first device and a target device, wherein the encryption key information comprises another encryption key and target device information identifying the target device associated with the other encryption key. ### Claim 10 (depends on 9) The computer program product according to claim 9, further comprising a computer-readable program code configured to provide information to the trusted device before receiving the encryption key information from the trusted device. ### Claim 11 (depends on 9) The computer program product according to claim 9, wherein the received encryption key information further includes information identifying the trusted device as source for the information. ### Claim 12 (depends on 9) The computer program product according to claim 9, further comprising a computer-readable program code configured to establish a secure link between the first device and the target device using the received encryption key information. ### Claim 13 A computer program product comprising a non-transitory computer usable medium having computer readable program code embodied in said medium, comprising: a computer-readable program code configured to establish a wireless link between an encountered device and a second device; a computer-readable program code configured to determine whether a trusted relationship exists between the second device and the encountered device by checking whether an encryption key associated with the encountered device is stored within the second device; a computer-readable program code configured to, if the encountered device is determined to be a trusted device, establish a secure link between the second device and the trusted device using the stored encryption key; a computer-readable program code configured to determine if encryption key information for establishing a secure link between the trusted device and a target device is to be transmitted to the trusted device via the secure link, wherein the encryption key information comprises another encryption key and target device information identifying the target device associated with the other encryption key, wherein said another encryption key is also for establishing a trusted relationship between the second device and the target device; and a computer-readable program code configured to, if it is determined that the encryption key information for establishing a secure link between the trusted device and the target device is to be transmitted, transmitting the encryption key information to the trusted device. ### Claim 14 (depends on 13) The computer program product according to claim 13, wherein the encryption key information for establishing a secure link with the target device is received through a trusted relationship with the target device. ### Claim 15 (depends on 13) The computer program product according to claim 13, wherein the computer-readable program code configured to determine if encryption key information for establishing a secure link between the trusted device and the target device is to be transmitted to the trusted device is based on information received from the trusted device. ### Claim 16 (depends on 13) The computer program product according to claim 13, wherein the encryption key information further includes information identifying the second device as source for the information. ### Claim 17 An apparatus, comprising: at least one processor; and at least one non-transitory memory including executable instructions, the at least one memory and the executable instructions being configured to, in cooperation with the at least one processor, cause the apparatus to: establish a wireless link between an encountered device and a first device; determine whether a trusted relationship exists between the first device and the encountered device by checking whether an encryption key associated with the encountered device is stored within the first device; if the encountered device is determined to be a trusted device, establish a secure link between the first device and the trusted device using the stored encryption key; and receive, in the first device, encryption key information from the trusted device via said secure link for establishing a secure link between the first device and a target device, wherein the encryption key information comprises another encryption key and target device information identifying the target device associated with the other encryption key. ### Claim 18 (depends on 17) The apparatus according to claim 17, wherein the at least one memory and the executable instructions are further configured to, in cooperation with the at least one processor cause the apparatus to provide information to the trusted device before receiving the encryption key information from the trusted device. ### Claim 19 (depends on 17) The apparatus according to claim 17, wherein the received encryption key information further includes information identifying the trusted device as source for the information. ### Claim 20 (depends on 17) The apparatus according to claim 17, wherein the at least one memory and the executable instructions are further configured to, in cooperation with the at least one processor cause the apparatus to establish a secure link between the first device and the target device using the received encryption key information. ### Claim 21 An apparatus, comprising: at least one processor; and at least one non-transitory memory including executable instructions, the at least one memory and the executable instructions being configured to, in cooperation with the at least one processor, cause the apparatus to: establish a wireless link between an encountered device and a second device; determine whether a trusted relationship exists between the second device and the encountered device by checking whether an encryption key associated with the encountered device is stored within the second device; if the encountered device is determined to be a trusted device, establish a secure link between the second device and the trusted device using the stored encryption key; determine if encryption key information for establishing a secure link between the trusted device and a target device is to be transmitted to the trusted device via the secure link, wherein the encryption key information comprises another encryption key and target device information identifying the target device associated with the other encryption key, wherein said another encryption key is also for establishing a trusted relationship between the second device and the target device; and if it is determined that the encryption key information for establishing a secure link between the trusted device and the target device is to be transmitted, transmitting the encryption key information to the trusted device. ### Claim 22 (depends on 21) The apparatus according to claim 21, wherein the at least one memory and the executable instructions are further configured to, in cooperation with the at least one processor cause the apparatus to receive the encryption key information for establishing a secure link with the target device. ### Claim 23 (depends on 21) The apparatus according to claim 21, wherein the at least one memory and the executable instructions are further configured to, in cooperation with the at least one processor cause the apparatus to determine if encryption key information for establishing a secure link between the trusted device and the target device is to be transmitted to the trusted device based on information received from the trusted device. ### Claim 24 (depends on 21) The apparatus according to claim 21, wherein the encryption key information further includes information identifying the second device as source for the information.