Method of communication apparatus, and method of user equipment (ue)

A method performed by a first communication apparatus, the method comprising:

• receiving a first message from a second communication apparatus for Network Slice Admission Control (NSAC) for a maximum number of User Equipments (UEs) with at least one Protocol Data Unit (PDU) session/Packet Data Network (PDN) connection based on a UE establishing a PDU session/PDN connection associated with a network slice in the second communication apparatus;
• and
• performing NSAC for the maximum number of UEs with at least one PDU session/PDN connection in case of EPC interworking.

A method performed by a second communication apparatus, the method comprising:

• sending a first message to a first communication apparatus for Network Slice Admission Control (NSAC) for a maximum number of User Equipments (UEs) with at least one Protocol Data Unit (PDU) session/Packet Data Network (PDN) connection based on a UE establishing a PDU session/PDN connection associated with a network slice in the second communication apparatus;
• and
• receiving a second message from the first communication apparatus based on the first message being received by the first communication apparatus and a current number of UEs with at least one PDU session/PDN connection has already been reached to the maximum number of UEs.