Application topology aware user plane selection in NR and 5GC

A physical network node that hosts a session management function, SMF, in a core network in a cellular communications network that comprises a radio access network and the core network, the SMF being a logical network node and the physical network node comprising:

• at least one processor;
• and
• memory comprising instructions executable by the at least one processor whereby the physical network node is operable to implement the SMF, the SMF being operable to:
• receive information regarding one or more candidate Packet Processing Functions, PPFs, in the radio access network;
• determine one or more candidate User Plane Functions, UPFs, based on the one or more candidate PPFs;
• send, to an Application Function, AF, a message comprising information regarding the one or more candidate PPFs and the one or more candidate UPFs;
• receive, from the AF, information related to Application Server, AS, selection, wherein the AS is selected by the AF based on the information regarding the one or more candidate PPFs and the one or more candidate UPFs;
• and
• select a user plane function for a protocol data unit session for a wireless device based on the information related to AS selection such that the protocol data unit session for the wireless device utilizes the selected user plane function,
• wherein the information related to AS selection comprises information that indicates at least one PPF pool comprising the one or more candidate PPFs related to the selected AS selected by the AF and information that identifies the selected AS.

A method of operation for assisting in coordinated selection of an Application Server, AS, and a user plane function in a cellular communications network for a protocol data unit session for a wireless device, comprising:

• receiving, from a session management function, SMF, of the cellular communications network, a message comprising information regarding two or more candidate Packet Processing Functions, PPFs, and two or more candidate User Plane Functions, UPFs, for the protocol data unit session for the wireless device, wherein the two or more candidate UPFs are determined at the SMF based on the two or more candidate PPFs;
• selecting the AS based on the received information regarding the two or more candidate PPFs and the two or more candidate UPFs;
• and
• providing, to the SMF, information related to AS selection, wherein the information related to AS selection comprises information that indicates at least one PPF pool comprising the two or more candidate PPFs related to the selected AS and information that identifies the selected AS.

A physical network node that hosts an Application Function, AF, for assisting in coordinated selection of an Application Server, AS, and a user plane function in a cellular communications network for a protocol data unit session for a wireless device, the AF being a logical network node and the physical network node comprising:

• at least one processor;
• and
• memory comprising instructions executable by the at least one processor whereby the physical network node is operable to implement the AF, the AF being operable to:
• receive, from a session management function, SMF, of the cellular communications network, a message comprising information regarding two or more candidate Packet Processing Functions, PPFs, and two or more candidate User Plane Functions, UPFs, for the protocol data unit session for the wireless device, wherein the two or more candidate UPFs are determined at the SMF based on the two or more candidate PPFs;
• select the AS based on the received information regarding the two or more candidate PPFs and the two or more candidate UPFs;
• and
• provide, to the SMF, information related to AS selection, wherein the information related to AS selection comprises information that indicates at least one PPF pool comprising the two or more candidate PPFs related to the selected AS and information that identifies the selected AS.

A method of operation of an Application Function, AF, for assisting in coordinated selection of an Application Server, AS, and a user plane function in a cellular communications network for a protocol data unit session for a wireless device, comprising:

• receiving, from a session management function, SMF, of the cellular communications network, a request for possible AS locations, the request comprises information regarding one or more candidate Packet Processing Functions, PPFs, and one or more candidate User Plane Functions, UPFs, wherein the one or more candidate UPFs are determined at the SMF based on the one or more candidate PPFs;
• determining a plurality of possible AS locations based on the information regarding the one or more candidate PPFs and the one or more candidate UPFs;
• and
• sending, to the SMF, information that indicates the plurality of possible AS locations, the information indicating at least one PPF pool comprising the one or more candidate PPFs related to each of the plurality of possible AS locations.