US 12,470,918 B2
Communication terminal, core network device, core network node, network node, and key deriving method
Hironori Ito, Tokyo (JP); Sivakamy Lakshminarayanan, Chennai (IN); Anand Raghawa Prasad, Tokyo (JP); Sivabalan Arumugam, Chennai (IN); and Sheeba Backia Mary Baskaran, Chennai (IN)
Assigned to NEC CORPORATION, Tokyo (JP)
Filed by NEC Corporation, Tokyo (JP)
Filed on Feb. 7, 2024, as Appl. No. 18/435,148.
Application 18/435,148 is a continuation of application No. 16/650,997, granted, now 11,937,079, previously published as PCT/JP2018/036074, filed on Sep. 27, 2018.
Claims priority of application No. 201711034337 (IN), filed on Sep. 27, 2017.
Prior Publication US 2024/0244425 A1, Jul. 18, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H04W 12/041 (2021.01); H04L 9/40 (2022.01); H04W 12/06 (2021.01)
CPC H04W 12/041 (2021.01) [H04L 63/18 (2013.01); H04W 12/06 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method performed by a User Equipment (UE), the method comprising:
deriving a first security key based on at least a first fixed value of an access type distinguisher, wherein the first fixed value indicates 3rd Generation Partnership Project (3GPP) access and is different from a second fixed value of the access type distinguisher indicating Non-3GPP access;
deriving a second security key based on the first security key; and
protecting a Radio Resource Control (RRC) message transmitted between the UE and the 3GPP access, based on the second security key,
wherein the first security key is derived using the first fixed value and a count value for Non Access Stratum (NAS).