Improvement of Handoff Latency by GPS Based Handoff Technique

Presently IEEE 802.11b based wireless networks are being widely used in various fields like personal as well as business applications. Handoff is a critical issue in IEEE 802.11b based wireless networks. When a mobile node (MN) moves away from the range of its current access point (AP) it needs to perform a link layer handoff. This causes data loss and interruption in communication. According to IEEE 802.11b link layer2 (L2) handoff consists of three phases – scanning, authentication and re-association. Scanning process delay is 90% of the total handoff delay. So in this paper we propose a better scanning mechanism to reduce handoff latency. Using GPS we determine the direction of velocity of the MN as well as position. It reduces the time to find the closest and best AP among all neighbor APs. This process effectively reduces the handoff latency.