Pre-Authenticated Fast Handoff in a Public Wireless LAN Based on IEEE 802.1x Model

With the popularity of portable devices, public Internet access service using wireless LAN has started in many countries. In the public wireless LAN network, since re-authentication latency during handoff affects the service quality of multimedia applications, minimizing authentication latency is very important in order to support real-time multimedia applications on the wireless IP network. In this paper, we proposed a fast handoff scheme using the predictive authentication method based on IEEE 802.1x model. In our scheme, a mobile host entering an area of an access point (AP) performs authentication procedures for a set of multiple APs instead of the current AP. Multiple APs are selected using a Frequent Handoff Region (FHR) selection algorithm considering users' mobility patterns and their service classes. Since a mobile host is authenticated for FHR in advance, the handoff latency due to the reauthentication can be minimized. Simulation results show that the proposed scheme is more efficient than other schemes in terms of delay.