US 12,425,849 B2
Method and apparatus for obtaining key, user equipment, and network side device
Wenjuan Pu, Dongguan (CN); Xiaodong Yang, Dongguan (CN); Wei Bao, Dongguan (CN); Xuanbing Liu, Dongguan (CN); and Fei Qin, Dongguan (CN)
Assigned to VIVO MOBILE COMMUNICATION CO., LTD., Guangdong (CN)
Filed by VIVO MOBILE COMMUNICATION CO., LTD., Dongguan (CN)
Filed on Nov. 23, 2022, as Appl. No. 18/058,567.
Application 18/058,567 is a continuation of application No. PCT/CN2021/096533, filed on May 27, 2021.
Claims priority of application No. 202010463814.4 (CN), filed on May 27, 2020.
Prior Publication US 2023/0079410 A1, Mar. 16, 2023
Int. Cl. H04W 12/03 (2021.01); H04W 12/0471 (2021.01)
CPC H04W 12/0471 (2021.01) [H04W 12/03 (2021.01)] 14 Claims
OG exemplary drawing
 
1. A method for obtaining a key, comprising:
sending, by a first user equipment (UE), first key information to a network side device; wherein
the first key information is used for indicating a first key of a second UE, and the first key of the second UE is used for performing encryption and/or integrity protection on data in communication between the second UE and the network side device; wherein
before sending, by the first UE, the first key information to the network side device, the method further comprises:
calculating, by the first UE, the first key of the second UE according to target information and an input parameter; wherein
the target information comprises first information or a security key of the first UE;
the first information is a same parameter or a related parameter stored in the first UE and the second UE; the security key of the first UE comprises a first subkey and a second subkey; the first subkey is a key related to a first access network element; and the second subkey is a key related to a second access network element; and
the input parameter comprises at least one of following: a target parameter, a physical cell identifier (PCI) of a cell in which the second UE is located, frequency information of a cell in which the second UE is located, or device information of the second UE; and the target parameter comprises at least one of following: a counter, a random number, or a sequence; and/or
before sending, by the first UE, the first key information to the network side device, the method further comprises:
receiving, by the first UE, a key request from the second UE; wherein
the key request is used for requesting to use a security key of the first UE to perform encryption and/or integrity protection on data in communication between the second UE and the network side device; the security key comprises a first subkey and a second subkey; and the first subkey is a key related to a first access network element, and the second subkey is a key related to a second access network element; and
using, by the first UE, the security key of the first UE as the first key of the second UE according to the key request.