A QoS guaranteed fast handoff algorithm for wireless local area network environments

Proposed CCRSVP (CandidateCasting RSVP) algorithm is a new fast handoff method for IEEE 802.11 Wireless LAN (WLAN) environments. It shows good performance in the handoff latency and the bandwidth efficiency aspect and guarantees QoS because it uses an advanced multicasting method and RSVP. CCRSVP uses L2 information (BSSID) of WLAN and starts reserving resources and multicasting packets before L2 handoff completes. Therefore, the proposed algorithm can reduce L3 handoff latency more than other methods. To show performance of CCRSVP algorithm, we calculate handoff latency and packet loss ratio of each algorithm. Also we model handoff process which uses RSVP mechanism to confirm resource efficiency. Proposed handoff model uses parameters which can distinguish each handoff algorithm. We introduce Markov, chain which can analyze handoff model and analysis method which uses iteration method. In this article, the results show that the proposed algorithm shows superior bandwidth efficiency than existing L3 handoff algorithms using RSVP. To analyze bandwidth efficiency of each algorithm, we compare the blocking probability which occurs in case of absence of resource, resource usage which shows reservation quantity, the average number of ongoing session which really uses resource reserved and resource utilization. We can confirm that CCRSVP algorithm has better performance than other algorithms at each comparative item.