An Adaptive and Preemptive Algorithm for Faster Handoffs in WLAN

Abstract

IEEE 802.11 Wireless LANs have shown enormous growth in recent times. Due to the mobility promises shown by them, seamless roaming has become a critical component of the whole deployment. A handoff occurs when a Mobile Station moves away from transmission range of one Access Point and enters into transmission range of another Access Point. The current handoff procedure does not satisfy the jitter requirements for real time multimedia applications like VoIP. In this paper we propose a new handoff algorithm which reduces handoff latency to an extent to be seamlessly bearable by a multimedia application. We reduce the search phase latency by periodically scanning channels one at a time and caching the results. The cached results can be used be used for future handoff management.