Amf re-allocation due to slicing

Abstract

In a wireless communication network implementing network slicing (NS), an Initial Access and Mobility Management Function (AMF) for a user equipment (UE) in one NS is able to re-allocate a UE to a Target AMF in a different NS, despite not being able to directly communicate with the Target AMF due to NS security restrictions. In a first embodiment, the Initial AMF transfers the UE context—including its security context—to a Default AMF. The Default AMF has the capability to communicate with network functions in different NSes. The Default AMF transfers the UE context to the Target AMF. In a second embodiment, a security key Kamf' is horizontally derived in a manner that avoids NS security conflicts. The derived key is transferred to the UE and Target AMF, which establish a security context. In a third embodiment, the Initial AMF allocates a Token, and transfers it, along with the UE security context (directly or via RAN) to the Default AMF. The Default AMF then transfers the security context to the Target AMF.