Device and method for supporting conditional handover in wireless communication system

A method performed by a central unit-user plane (CU-UP) of a base station (BS), the method comprising:

• receiving, from a CU-CP of the BS, a bearer context setup request message, wherein the bearer context setup request message includes information for indicating a conditional handover which is a handover executed by a user equipment (UE) when at least one execution condition is satisfied;
• and
• transmitting, to the CU-CP, a bearer context setup response message;
• and
• performing a bearer context modification procedure,
• wherein inactivity monitoring of the CU-UP is performed after a bearer context modification procedure, in case of a conditional handover.

A method performed by a distributed unit (DU) of a base station (BS), the method comprising:

• receiving, from a central unit-control plane (CU-CP) of the BS, a UE context setup request message, wherein the UE context setup request message includes information for indicating a conditional handover which is a handover executed by a UE when at least one execution condition is satisfied;
• and
• transmitting, to the CU-CP, a UE context setup response message;
• wherein the DU is configured to stop an operation for detecting a radio link failure (RLF) based on the conditional handover.

An apparatus of a central unit (CU)-control plane (CP) of a base station (BS), the apparatus comprising:

• at least one transceiver;
• and
• at least one processor coupled with the at least one processor and configured to:
• transmit, to a CU-user plane (UP) of the BS, a bearer context setup request message, wherein the bearer context setup request message includes information for indicating a conditional handover which is a handover executed by a user equipment (UE) when at least one execution condition is satisfied,
• receive, from the CU-UP, a bearer context setup response from the CU-UP, and
• perform a bearer context modification procedure,
• wherein inactivity monitoring of the CU-UP is performed after a bearer context modification procedure, in case of a conditional handover.

An apparatus of a central unit-user plane (CU-UP) of a base station (BS), the apparatus comprising:

• at least one transceiver;
• and
• at least one processor coupled with the at least one processor and configured to:
• receive, from a CU-CP of the BS, a bearer context setup request message, wherein the bearer context setup request message includes information for indicating a conditional handover which is a handover executed by a user equipment (UE) when at least one execution condition is satisfied,
• transmit, to the CU-CP, a bearer context setup response message, and
• perform a bearer context modification procedure,
• wherein inactivity monitoring of the CU-UP is performed after a bearer context modification procedure, in case of a conditional handover.

An apparatus of a distributed unit (DU) of a base station (BS), the apparatus comprising:

• at least one transceiver;
• and
• at least one processor coupled with the at least one processor and configured to:
• receive, from a central unit-control plane (CU-CP) of the BS, a UE context setup request message, wherein the UE context setup request message includes information for indicating a conditional handover which is a handover executed by a UE when at least one execution condition is satisfied, and
• transmit, to the CU-CP, a UE context setup response message,
• wherein the DU is configured to stop an operation for detecting a radio link failure (RLF) based on the conditional handover.