Method and apparatus for determining protocol data unit session service network element

A communications system comprising:

• a mobility management device configured to:
• receive a request for establishing a first protocol data unit (PDU) session from a terminal, wherein the request comprises a first data network name (DNN) that the first PDU session is to be connected;
• and
• send the request;
• and
• a first control plane function network element configured to:
• receive the request from the mobility management device;
• determine, based on the first DNN that the first PDU session is to be connected, to select a first user plane function network element for the first PDU session;
• and
• select, for the first PDU session, the first user plane function network element, wherein the first user plane function network element is for serving an established PDU session connected to the first DNN.

An apparatus, comprising:

• at least one processor;
• and
• a memory coupled to the at least one processor and having program instructions stored thereon which, when executed by the at least one processor, cause the apparatus to:
• receive, from a first mobility management device, a request for establishing a first protocol data unit (PDU) session, wherein the request comprises a first data network name (DNN) that the first PDU session is to be connected;
• determine, based on the first DNN that the first PDU session to be connected, to select a first user plane function network element for the first PDU session;
• and
• select, for the first PDU session, the first user plane function network element, wherein the first user plane function network element is for serving an established PDU session connected to the first DNN.