Secure and Fast Roaming in 802.11 WLANS

The mass deployment of IEEE 802.11 based wireless local area networks (WLANs) and the popularity of portable devices created an urgent need to support voice and multimedia applications. However, these applications require fast handoff among access points (APs) while users are on the move for maintaining quality of connections and services continuity. In this paper, we firstly discuss the WLAN roaming problem showing the importance of minimizing re-authentication latency for real-time multimedia applications’ support. We then present IEEE standards support to roaming capabilities mainly focusing on 802.11i and 802.11r standards, and we point up some vendor-specific solutions for roaming enhancements, based on 802.11i. Furthermore, we present the IETF efforts in enhancing authentication performance for seamless roaming. We end this paper by showing the advantages and shortcomings of the presented roaming support approaches, highlighting some critical factors that need to be fulfilled in WLAN deployments for achieving fast and secure roaming