Coordinated selection of user plane functions in core and radio access networks

Abstract

Systems and methods are disclosed herein for coordinated selection of a User Plane Function (UPF) in a core network and a Packet Processing Function (PPF) in a radio access network. In some embodiments, a method of operation of network node of a cellular communications network to enable coordinated UPF and PPF selection comprises receiving information indicative of a UPF selected for a protocol data unit session of a wireless device, where the UPF is part of a core network of the cellular communications network. The method further comprises selecting a PPF for the protocol data unit session of the wireless device based on the information indicative of the UPF selected for the protocol data unit session of the wireless device, where the PPF is part of a radio access network of the cellular communications network. In this manner, an optimal routing of user data traffic can be achieved.

What is claimed is: 
     
         1 . A method of operation of a network node of a cellular communications network to enable coordinated User Plane Function, UPF, and Packet Processing Function, PPF, selection, comprising:
 at a Session Management Function, SMF:
 selecting a UPF and a UPF pool for a protocol data unit session of a wireless device, the UPF being part of a core network of the cellular communications network; and 
 sending, to an Access and Mobility Management Function, AMF, a message comprising information indicative of the UPF selected for the protocol data unit session of the wireless device, the information indicative of the UPF comprising the UPF pool selected for the protocol data unit session. 
   
     
     
         2 . The method of  claim 1  wherein the information indicative of the UPF comprises UPF information for the UPF. 
     
     
         3 . The method of  claim 1  wherein the information indicative of the UPF comprises information that identifies a name or location of the UPF. 
     
     
         4 . The method of  claim 1  wherein the information indicative of the UPF comprises a UPF pool identity for the UPF, a UPF name of the UPF, a UPF address of the UPF, or a UPF location of the UPF. 
     
     
         5 . The method of  claim 1  further comprising sending a session establishment request to the UPF. 
     
     
         6 . The method of  claim 1  further comprising:
 receiving, from another network node, a message comprising a transport address and tunnel endpoint identifier of a PPF selected for the protocol data unit session of the wireless device, the PPF being part of a radio access network of the cellular communications network; and 
 sending, to the UPF, a message comprising the transport address and the tunnel endpoint identifier of the PPF selected for the protocol data unit session of the wireless device. 
 
     
     
         7 . The method of  claim 1  wherein selecting the UPF for the protocol data unit session of the wireless device comprises selecting the UPF for the protocol data unit session of the wireless device as part of an initial attachment procedure. 
     
     
         8 . The method of  claim 1  wherein selecting the UPF for the protocol data unit session of the wireless device comprises selecting the UPF for the protocol data unit session of the wireless device as part of a reselection or reallocation procedure. 
     
     
         9 . The method of  claim 1  wherein the PPF is logically separated from a Radio Control Function, RCF, the PPF is physically and logically separated from the RCF, or the PPF is physically and logically co-located with the RCF. 
     
     
         10 . A network node of a cellular communications network for enabling coordinated User Plane Function, UPF, and Packet Processing Function, PPF, selection, comprising:
 a Session Management Function, SMF, comprising:
 at least one processor; and 
 memory comprising instructions executable by the at least one processor whereby the network node is operable to:
 select a UPF and a UPF pool for a protocol data unit session of a wireless device, the UPF being part of a core network of the cellular communications network; and 
 send, to an Access and Mobility Management Function, AMF, a message comprising information indicative of the UPF selected for the protocol data unit session of the wireless device, the information indicative of the UPF comprising the UPF pool selected for the protocol data unit session.