A smooth handoff scheme using IEEE802.11 triggers: design and implementation

This paper proposes a handoff scheme in a wireless access network where IEEE802.11 is used as link layer protocol and Mobile IP as network layer protocol. The scheme uses triggers available from IEEE802.11, together with packet buffering in the old Access Point and packet forwarding from the old to the new Access Point in order to provide a smooth handoff. The proposed scheme has been implemented on a Linux based testbed and it has been analysed by means of an ns simulation and an analytical model. The paper reports on the results obtained from the testbed, the simulation and the analytical model, both for constant bit rate traffic (in particular streamed RTP video) and TCP traffic.