Access and mobility management function, amf, shared radio access network, ran, and method

A shared Radio Access Network (RAN) comprising:

• a memory storing instructions;
• and
• a processor configured to execute the instructions to:
• receive, form a first Access and Mobility Management Function (AMF) belonging to a first Public Land Mobile Network (PLMN), a second message including at least second information associated with a proxy request,
• transmit, to the first AMF, an acknowledge message,
• receive, from a user equipment (UE), a Radio Resource Control (RRC) message including at least a selected Public Land Mobile Network (PLMN)-Identity, and
• determine whether to transmit a first Next Generation Application Protocol (NGAP) message, to a second AMF belonging to a second PLMN, directly or via the first AMF.

A method for a first Access and Mobility Management Function (AMF), belonging to a first Public Land Mobile Network (PLMN), the method comprising:

• receiving, from a second AMF belonging a second PLMN, a first message including at least first information associated with a proxy request,
• selecting at least one shared Radio Access Network (RAN) from among multiple shared RAN candidates,
• transmitting, to the at least one selected shared RAN, a second message including at least second information associated with the proxy request,
• receiving, from the at least one selected shared RAN, an acknowledge message, and
• transmitting, to the second AMF, a third message including at least third information associated with the at least one selected shared RAN.