Method and apparatus for controlling UE context in wireless communication system

A method of a second node in a wireless communication system, the method comprising:

• receiving, from a first node, a user equipment (UE) context modification required message to request a UE context modification, wherein a procedure of the UE context modification is initiated by a message requesting an operation of the UE context modification, transmitted from the second node to a third node, and wherein the UE context modification is performed between a UE and the third node;
• transmitting, to the first node, a confirm message, in case that the procedure of UE context modification is successful;
• and
• transmitting, to the first node, a refuse message in case that the UE context modification is unsuccessful,
• wherein the refuse message includes information on a cause for identifying a reason for a UE context modification failure,
• wherein the first node and the second node operate based on a first radio access technology (RAT), and the third node operates based on a second RAT, and
• wherein the first node is a distributed unit (DU) and the second node is a central unit (CU).

A first node in a wireless communication system, the first node comprising:

• a transceiver;
• and
• at least one processor configured to:
• control the transceiver to transmit, to a second node, a user equipment (UE) context modification required message to request a UE context modification,
• control the transceiver to receive, from the second node, a response message for the UE context modification required message, wherein a procedure of the UE context modification is initiated by a message requesting an operation of the UE context modification, transmitted from the second node to a third node, and wherein the UE context modification is performed between a UE and the third node, and
• identify, in case that the response message is a refuse message to indicate the UE context modification being unsuccessful, a reason for a UE context modification failure based on information on a cause included in the refuse message,
• wherein the first node and the second node operate based on a first radio access technology (RAT), and the third node operates based on a second RAT, and
• wherein the first node is a distributed unit (DU) and the second node is a central unit (CU).

A second node in a wireless communication system, the second node comprising:

• a transceiver;
• and
• at least one processor configured to control the transceiver to:
• control the transceiver to receive, from a first node, a user equipment (UE) context modification required message to request a UE context modification, wherein a procedure of the UE context modification is initiated by a message requesting an operation of the UE context modification, transmitted from the second node to a third node, and wherein the UE context modification is performed between a UE and the third node,
• control the transceiver to transmit, to the first node, a confirm message, in case that the UE context modification is successful, and
• control the transceiver to transmit, to the first node, a refuse message in case that the UE context modification is unsuccessful,
• wherein the refuse message includes information on a cause for identifying a reason for a UE context modification failure,
• wherein the first node and the second node operate based on a first radio access technology (RAT), and the third node operates based on a second RAT, and
• wherein the first node is a distributed unit (DU) and the second node is a central unit (CU).