Systems and methods are described herein for optimizing the signaling between a User Plane Function (UPF) and a Session Management Function (SMF) during Handoff (HO) and Evolved Packet System (EPS)-Interworking cases. The systems and methods may be employed to intimate "End-Marker" notification from a UPF to a Source Radio Access Network (Source-RAN) of a respective 4G/5G Access-Network. This is achieved by introducing Send End Marker Packets (SNDEM) flags in "Remove FAR" as part of an N4 Session Modification Request.

The solution described herein is applicable where a SMF has selected the same or different UPF to interact with a target RAN (T-RAN) based on slice information provided by Network Slice Selection Function (NSSF).

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.