Method and apparatus for transmitting and receiving data in wireless communication system

A centralized unit (CU)-user plane (UP) of a base station in a wireless communication system, the CU-UP comprising:

• a transceiver;
• and
• at least one processor coupled with the transceiver and configured to:
• receive, from a CU-control plane (CP) of the base station, a bearer context modification request message,
• wherein the bearer context modification request message comprises information associated with a request for a packet data convergence protocol (PDCP) sequence number (SN) status, and
• transmit, based on the bearer context modification request message, a bearer context modification response message to the CU-CP of the base station,
• wherein the bearer context modification response message comprises information associated with the PDCP SN status and information indicating at least one quality of service (QoS) flow, of which a service data adaptation protocol (SDAP) end marker is not received by the CU-UP of the base station.

A method performed by a centralized unit (CU)-control plane (CP) of a base station in a wireless communication system, the method comprising:

• transmitting a bearer context modification request message to a CU-user plane (UP) of the base station,
• wherein the bearer context modification request message comprises information associated with a request for a packet data convergence protocol (PDCP) sequence number (SN) status;
• and
• receiving, based on the bearer context modification request message, a bearer context modification response message from the CU-UP of the base station,
• wherein the bearer context modification response message comprises information associated with the PDCP SN status and information indicating at least one quality of service (QoS) flow, of which a service data adaptation protocol (SDAP) end marker is not received by the CU-UP of the base station.

A centralized unit (CU)-control plane (CP) of a base station in a wireless communication system, the CU-CP comprising:

• a transceiver;
• and
• at least one processor coupled with the transceiver and configured to:
• transmit a bearer context modification request message to a CU-user plane (UP),
• wherein the bearer context modification request message comprises information associated with a request for a packet data convergence protocol (PDCP) sequence number (SN) status, and
• receive, based on the bearer context modification request message, a bearer context modification response message from the CU-UP of the base station,
• wherein the bearer context modification response message comprises information associated with the PDCP SN status and information indicating at least one quality of service (QoS) flow, of which a service data adaptation protocol (SDAP) end marker is not received by the CU-UP of the base station.