Amf relocation with n3iwf handling

A method performed by a target Access and Mobility Management Function (AMF) of a core network, comprising:

• receiving a request of the wireless communication device to register for 3GPP access with the core network;
• acquiring a current user equipment (UE) context of the wireless communication device, an identifier of an ongoing non-3rd Generation Partnership Project (non-3GPP) access Protocol Data Unit (PDU) session, and destination information for a Non-3GPP Interworking Function (N3IWF) associated with the wireless communication device for enabling the wireless communication device to attach to the core network;
• notifying a Session Management Function (SMF) handling the ongoing non-3GPP access PDU session that the wireless communication device will be relocated from the currently serving AMF to the target AMF;
• notifying the N3IWF designated by the destination information to redirect any further signalling of the wireless communication device from the currently serving AMF to the target AMF;
• and
• notifying the wireless communication device that the registration with the target AMF for a 3GPP access is successful.

A method performed by a Non-3rd Generation Partnership Project (3GPP) Interworking Function (N3IWF) enabling a wireless communication device (WCD) to attach to a core network over non-3GPP access, to facilitate re-location of the wireless communication device from a source Access and Mobility Management Function (AMF) currently serving the WCD over non-3GPP access to a target AMF which is to serve the WCD over 3GPP access, comprising:

• receiving, from the target AMF, a redirect request to redirect signalling of the WCD from the source AMF currently serving the WCD to the target AMF;
• after receiving the redirect request, receiving signalling transmitted by the WCD;
• and
• as a result of receiving the redirect request transmitted by the target AMF, transmitting the received signalling to the target AMF rather than the source AMF.

A method performed by a wireless communication device (WCD), the wireless communication device being registered with a core network over non-3rd Generation Partnership Project (3GPP) access with a currently serving Access and Mobility Management Function (AMF), comprising:

• submitting a request to register for 3GPP access with the core network via a target AMF to which the wireless communication device is to be relocated from the currently serving AMF providing non-3GPP access to the core network;
• receiving a notification from the target AMF that the registration for 3GPP access is successful;
• and
• submitting, via a Non-3GPP Interworking Function (N3IWF) enabling the wireless communication device to remain connected via non-3GPP access, a request for non-3GPP access to the core network to the target AMF to which the wireless communication device has been relocated.