METHOD AND APPARATUS FOR TRACKING DATA PACKETS IN A PACKET DATA COMMUNICATION SYSTEM

摘要

A communication system (200) that includes a mobile station (MS) (202) in wireless communication with an infrastructure (210) comprising a Serving GPRS Support Node (SGSN) (250) operably coupled to a Packet Control Unit (PCU) (230) utilizes a synchronization message (242) conveyed by the SGSN to the PCU and a synchronization message acknowledgment (244) conveyed by the PCU to the SGSN to determine the data provided to the MS, provide correct accounting information and lost data packet recovery, and allow the SGSN to control a flow of data packets to the PCU. Furthermore, an SGSN synchronization buffer (258) stores copies of data packets conveyed by the SGSN to the PCU, allowing the SGSN to reconvey lost data packets to the serving PCU (230) and to convey, to a target PCU (266), data packets conveyed by the SGSN to the serving PCU but not conveyed by the serving PCU to the MS.