Transfer of communication sessions between base stations in wireless networks

Abstract

A method for carrying out a handover procedure, following which a mobile terminal (MS) currently in communication with a first base station (BS), will communicate via a second BS. The method includes upon initiating a handover procedure, determining that the MS will receive all future IP packets via the second base station, following this determination and prior to establishing a connection between the MS and the second BS, forwarding all IP packets being addressed to the MS to the second BS, and buffering the received IP packets thereat, and upon establishing a connection between the MS and the second BS, forwarding the IP packets that were buffered at the second BS to the MS, wherein the buffered IP packets are delivered to the MS before delivering any packets addressed thereto along a new path extending to the second BS which does not include the first BS.

We claim: 
     
         1 . A method for use with handover in a wireless system, the wireless system comprising a first base station that communicates with a first gateway and other base stations that communicate with other gateways, said method comprising:
 determining that a mobile subscriber terminal that is receiving packets addressed to it via the first base station will handover to receive future packets via one of the other base stations;   following the handover determination and prior to establishing a connection between said mobile subscriber terminal and said one of the other base stations, receiving from the mobile subscriber terminal at the first gateway a list of candidate base stations;   multicasting from the first gateway packets addressed to said mobile subscriber terminal to the first base station and to the candidate base stations via respective gateways associated with the candidate base stations;   establishing a connection between said mobile subscriber terminal and a second base station, said second base station being one of the candidate base stations; and   following establishing the connection between said mobile subscriber terminal and said second base station, forwarding from the second base station to said mobile subscriber terminal the packets addressed to said mobile subscriber terminal.