Method and device for supporting session continuity by considering maximum allowable bit rate in wireless communication system

An operating method of an Access And Mobility Management Function (AMF) entity in a wireless communication system, the operating method comprising:

• receiving, from a user equipment (UE), a Protocol Data Unit (PDU) session creation request message;
• selecting a Session Management Function (SMF) entity for a new PDU Session;
• transmitting, to the selected SMF entity, the PDU session creation request message;
• and
• receiving, from the SMF entity, a response message with respect to the PDU session creation request message.

A Session Management Function (SMF) entity for supporting session continuity by considering a maximum bitrate (MBR) in a wireless communication system, the SMF entity comprising:

• a transceiver;
• and
• at least one processor,
• wherein the at least one processor is configured to
• receive, from an Access And Mobility Management Function (AMF) entity, a Protocol Data Unit (PDU) session creation request message, receive, from a Unified Data Management (UDM) entity, subscriber information associated with a session of a user equipment (UE),
• transmit, to the AMF entity, a response message with respect to the PDU session creation request message,
• select a Policy Control Function (PCF) entity,
• transmit, to the selected PCF entity, a session management policy information creation request message comprising Session Migration Information,
• receive, from the PCF entity, policy information about a PDU Session which is determined based on a maximum bitrate (MBR) value (UE-Slice-MBR) corresponding to a slice for the PDU Session, and
• select a User Plane Function (UPF) entity to support session continuity by considering an MBR, based on the policy information about a PDU Session.