US 12,238,514 B2
Security key generation for handling data transmissions from user devices in an inactive state
Fangli Xu, Beijing (CN); Shu Guo, Beijing (CN); Yuqin Chen, Beijing (CN); Haijing Hu, Los Gatos, CA (US); Huarui Liang, Beijing (CN); and Dawei Zhang, Saratoga, CA (US)
Assigned to Apple Inc., Cupertino, CA (US)
Appl. No. 17/593,676
Filed by Apple Inc., Cupertino, CA (US)
PCT Filed Jul. 31, 2020, PCT No. PCT/CN2020/106198
§ 371(c)(1), (2) Date Sep. 22, 2021,
PCT Pub. No. WO2022/021323, PCT Pub. Date Feb. 3, 2022.
Prior Publication US 2023/0144223 A1, May 11, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04W 12/041 (2021.01); H04W 12/043 (2021.01); H04W 76/20 (2018.01); H04W 76/30 (2018.01)
CPC H04W 12/041 (2021.01) [H04W 12/043 (2021.01); H04W 76/20 (2018.02); H04W 76/30 (2018.02)] 18 Claims
OG exemplary drawing
 
1. A method for security key derivation in a wireless system, comprising:
sending a radio resource control (RRC) suspend message from a first node, to a first user device, the RRC suspend message including a first next hop (NH) chaining counter (NCC) value of multiple NCC values;
releasing access stratum (AS) resources associated with the first user device;
deriving a first node key based on the first NCC value for use in the RRC inactive state;
receiving a first uplink message from the first user device without allocating AS resources to the first user device;
unscrambling the first uplink message based on the first NCC value;
deriving a second node key based on a second NCC value of the multiple NCC values;
receiving a second uplink message from the first user device without allocating AS resources to the first user device;
unscrambling the second uplink message based on the second node key;
receiving a RRC resume request from the first user device after each NCC value of the multiple NCC values have been used to derive a node key; and
transmitting another RRC suspend message that includes another set of multiple NCC values to the first user device.