Section: 6.8.9.1 UMTS security context
Content: A UMTS security context is only established for UMTS subscribers. At the network side, two cases are distinguished: a) In case of a PS intra SGSN Handover, the UMTS cipher/integrity keys CK and IK agreed during the latest UMTS AKA procedure are sent to the target RNC or BSC. b) In case of a PS inter SGSN Handover, the initial SGSN sends the UMTS cipher/integrity keys CK and IK agreed during the latest UMTS AKA procedure to the new SGSN controlling the target RNC or BSC. The new SGSN becomes the new anchor point for the service. The new SGSN then stores the UMTS cipher/integrity keys CK and IK and sends them to the target RNC or BSC. At the user side, in both cases, the ME applies the UMTS cipher/integrity keys CK and IK received from the USIM during the latest UMTS AKA procedure.