Method and apparatus for performing handover using packet data convergence protocol (PDCP) reordering in mobile communication system

摘要

Improving communication efficiency in handover re-establishing an ARQ entity in a mobile communication system is disclosed. The method includes transmitting first Packet Data Convergence Protocol (PDCP) Packet Data Units (PDUs) correctly received from the source cell, together with a special indication requiring reordering of the first POCP PDUs, from a Radio Link Control (RLC) receiving buffer to a POCP receiving entity when a handover command message from a source cell to a target cell is received; buffering the first POCP PDUs in a POCP PDU reordering buffer by the POCP receiving entity in response to the special indication; and when a second PDCP PDU is received from the target cell through a new RLC receiving entity for the target cell, outputting third PDCP PDUs up to a PDCP PDU before a first missing PDCP PDU having a sequence number higher than that of the second PDCP PDU from the PDCP reordering buffer. In the method, a POCP entity performs reordering, thereby improving efficiency of communication.