Research on the Handoff Mechanism of 802.11 WLAN Based on AP Pre-Forward

The IEEE 802.11 wireless LAN protocol includes sub-MAC layer and PHY layer. It supports mobile communication of a host, but a handoff algorithm is not supplied. When a mobile host （MH） moves from one AP coverage to another, the performance will be effected by the connection disruption. Some handoff methods are supplied by literatures, such as hard-handoff and smooth-handoff. But the performance of them are not high. From the aspects of handoff latency and loss rate, a novel handoff scheme based on AP pre-forward is proposed and its simulation is carried out. The simulation result shows that the whole performance of the proposed algorithm is higher than others.