# US 2025/0379727 A1 · Method and apparatus for fast key sharing between user devices in a wireless communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0379727 A1 - Document ID: US20250379727A1 - Status: Published application - Kind: A1 - Application number: 18/939,832 - Filed: 2024-11-07 - Published: 2025-12-11 - Earliest claimed: 2024-06-07 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Taewoo KIM; Jiin KIM; Jihye LEE - Web page: https://patentgrep.com/patent/US20250379727A1 ## CPC - H04L 9/0838: {Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these (network architectures or network communication protocols for key exchange in a packet data network H04L63/061)} - H04W 12/041: Key generation or derivation - H04W 12/047: without using a trusted network node as an anchor - H04W 12/06: Authentication - H04W 12/08: Access security - H04W 12/40: Security arrangements using identity modules - H04W 12/76: Group identity - 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 The present disclosure relates to a 5G communication system or a 6G communication system for supporting higher data rates beyond a 4G communication system, such as long term evolution (LTE). A method performed by a first device in a wireless communication system is provided. The method includes receiving, from a reader device, first information on whether the reader device supports a fast transaction and the reader device's access level, and identifying a method in which the reader device validates a second device, based on the first information, wherein the first device is an owner device validated by the reader device, and wherein the second device is a friend device not validated by the reader device. ## Claims ### Claim 1 A method performed by a first device in a wireless communication system, the method comprising: receiving, from a reader device, first information on whether the reader device supports a fast transaction and the reader device's access level; and identifying a method in which the reader device validates a second device, based on the first information, wherein the first device is an owner device validated by the reader device, and wherein the second device is a friend device not validated by the reader device. ### Claim 2 (depends on 1) The method of claim 1, further comprising: transmitting, to the second device, second information comprising the first device's cryptogram and the reader device's identifier in case that the fast transaction is supported. ### Claim 3 (depends on 2) The method of claim 2, wherein validation of the second device's access credential is based on the cryptogram, and wherein whether to perform the validation for the access credential is based on the access level of the reader device. ### Claim 4 (depends on 2) The method of claim 2, wherein decryption of the cryptogram is based on the second device's identifier. ### Claim 5 (depends on 1) The method of claim 1, wherein the receiving of the first information further comprises: receiving, from the reader device, an authorization command regarding the first device, and wherein the first information is included in the authorization command or the reader device's update request for the first device's access information. ### Claim 6 A method performed by a reader device in a wireless communication system, the method comprising: transmitting, to a first device, first information on whether the reader device supports a fast transaction and the reader device's access level; transmitting, to a second device, an authorization command, based on the first information; and receiving, from the second device, a response to the authorization command, wherein the response includes second information including a cryptogram and an identifier of a device, wherein a method in which the reader device validates the second device is based on the first information, wherein the first device is an owner device validated by the reader device, and wherein the second device is a friend device not validated by the reader device. ### Claim 7 (depends on 6) The method of claim 6, wherein, in case that the fast transaction is supported, the cryptogram is the first device's cryptogram. ### Claim 8 (depends on 6) The method of claim 6, wherein validation of the second device's access credential is based on the cryptogram, and wherein whether to perform the validation for the access credential is based on the access level of the reader device. ### Claim 9 (depends on 6) The method of claim 6, further comprising: in case that the identifier is not stored in the reader device, identifying the identifier as the second device's identifier; and decrypting the cryptogram, based on the reader device's private key. ### Claim 10 (depends on 6) The method of claim 6, wherein the transmitting of the first information further comprises: transmitting, to the first device, an authorization command regarding the first device, and wherein the first information is included in the authorization command or the reader device's update request for the first device's access information. ### Claim 11 A first device in a wireless communication system, the first device comprising: a transceiver; and at least one processor coupled with the transceiver and configured to: receive, from a reader device, first information on whether the reader device supports a fast transaction and the reader device's access level, and identify a method in which the reader device validates a second device, based on the first information, wherein the first device is an owner device validated by the reader device, and wherein the second device is a friend device not validated by the reader device. ### Claim 12 (depends on 11) The first device of claim 11, wherein the at least one processor is further configured to: transmit, to the second device, second information comprising the first device's cryptogram and the reader device's identifier in case that the fast transaction is supported. ### Claim 13 (depends on 12) The first device of claim 12, wherein validation of the second device's access credential is based on the cryptogram, and wherein whether to perform the validation for the access credential is based on the access level of the reader device. ### Claim 14 (depends on 12) The first device of claim 12, wherein decryption of the cryptogram is based on the second device's identifier. ### Claim 15 (depends on 11) The first device of claim 11, wherein the at least one processor is further configured to: receive, from the reader device, an authorization command regarding the first device, and wherein the first information is included in the authorization command or the reader device's update request for the first device's access information. ### Claim 16 A reader device in a wireless communication system, the reader device comprising: a transceiver; and at least one processor coupled with the transceiver and configured to: transmit, to a first device, first information on whether the reader device supports a fast transaction and the reader device's access level, transmit, to a second device, an authorization command, based on the first information, and receive, from the second device, a response to the authorization command, wherein the response includes second information including a cryptogram and an identifier of a device, wherein a method in which the reader device validates the second device is based on the first information, wherein the first device is an owner device validated by the reader device, and wherein the second device is a friend device not validated by the reader device. ### Claim 17 (depends on 16) The reader device of claim 16, wherein, in case that the fast transaction is supported, the cryptogram is the first device's cryptogram. ### Claim 18 (depends on 16) The reader device of claim 16, wherein validation of the second device's access credential is based on the cryptogram, and wherein whether to perform the validation for the access credential is based on the access level of the reader device. ### Claim 19 (depends on 16) The reader device of claim 16, wherein the at least one processor is further configured to: in case that the identifier is not stored in the reader device, identify the identifier as the second device's identifier, and decrypt the cryptogram, based on the reader device's private key. ### Claim 20 (depends on 16) The reader device of claim 16, wherein the at least one processor is further configured to: transmit, to the first device, an authorization command regarding the first device, and wherein the first information is included in the authorization command or the reader device's update request for the first device's access information.