US Patent 11483754 Handover handling for multi-access PDU session

A method of handling multi-access (MA) Protocol data unit (PDU) session handover is proposed. A UE and network can support Access Traffic Steering Switching and Splitting (ATSSS) functionalities to distribute traffic over 3GPP access and non-3GPP access for the established MA PDU session. An ATSSS-Supported UE first establishes a MA PDU Session on both 3GPP and non-3GPP access in a currently registered PLMN which is an ATSSS-Supported network. The UE then moves from the ATSSS-Supported network to an ATSSS-not-Supported network and finally reaches another ATSSS-Supported network. In one novel aspect, a solution is provided on how to handle the ongoing MA PDU Session with two accesses under handover scenarios between ATSSS-Supported and ATSSS-not-Supported networks. Furthermore, if the ongoing MA PDU Session cannot handover, a solution is provided on how to handle the MA PDU Session.