	US 12,192,832 B2
	Determining security keys
Patrik Rugeland, Stockholm (SE); Gunnar Mildh, Sollentuna (SE); and Julien Muller, Rennes (FR)
Assigned to TELEFONAKTIEBOLAGET LM ERICSSON (PUBL), Stockholm (SE)
Appl. No. 17/765,348
Filed by Telefonaktiebolaget LM Ericsson (PUBL), Stockholm (SE)
PCT Filed Sep. 30, 2020, PCT No. PCT/EP2020/077387 § 371(c)(1), (2) Date Mar. 30, 2022, PCT Pub. No. WO2021/064032, PCT Pub. Date Apr. 8, 2021.
Claims priority of provisional application 62/907,846, filed on Sep. 30, 2019.
Prior Publication US 2022/0394565 A1, Dec. 8, 2022
Int. Cl. H04W 36/00 (2009.01); H04W 12/041 (2021.01); H04W 36/28 (2009.01); H04W 36/36 (2009.01)

CPC H04W 36/0027 (2013.01) [H04W 12/041 (2021.01); H04W 36/0069 (2018.08); H04W 36/28 (2013.01); H04W 36/362 (2023.05); H04W 36/00835 (2018.08)]

19 Claims

1. A method performed by a wireless device for determining security keys, the method comprising:

for each candidate primary secondary cell (PSCell) of a plurality of candidate PSCells for conditional addition or conditional change by the wireless device for dual connectivity, receiving, from a network node, a respective value associated with the candidate PSCell, wherein the value associated with the candidate PSCell is different to the value associated with at least one other candidate PSCell;

when a condition associated with a first candidate PSCell of the plurality of candidate PSCells is fulfilled, determining a respective security key for communications between the wireless device and the first candidate PSCell, wherein the respective security key is determined based on a master key and the respective value associated with the first candidate PSCell, wherein the values associated with the candidate PSCells are associated with a first primary cell for the wireless device;

for each candidate PSCell, receiving, from the network node, a respective further value associated with the candidate PSCell, wherein the further value associated with the candidate PSCell is different to the value associated with the candidate PSCell and is different to the further value associated with at least one other candidate PSCell, and wherein the further values associated with the candidate PSCells are associated with a second primary cell for the wireless device; and

when a condition associated with a second candidate PSCell of the plurality of candidate PSCells is fulfilled, determining a respective security key for communications between the wireless device and the second candidate PSCell, wherein the respective security key is determined based on a master key and the respective further value associated with the second candidate PSCell, wherein the further values associated with the candidate PSCells are associated with a secondary primary cell for the wireless device.