A method for enabling a target base station to perform handover of a UE (user equipment) from a source base station to the target base station is provided. The method includes receiving a request for handover of the UE from the source base station, allocating a handover identifier for the UE and transmitting the handover identifier to the source base station. The handover identifier identifies the UE during handover. The UE can use the handover identifier which relatively occupies small amount of radio resources during handover or initial access process.