Minimizing Communication Interruptions Using Smart Proactive Channel Scanning Over IEEE 802.11 WLANs

摘要

Wireless connectivity is becoming pervasive in our lives as wireless networks and mobile devices have been undergoing a magnificent evolution. In this context, consumers demand to access to the wireless communication services anytime and anywhere with high performance. IEEE 802.11 wireless local area networks (WLANs) have a direct impact on this widespread use. Nevertheless, as any standard procedure, WLAN also has its own drawbacks. In IEEE 802.11 wireless networks, periodic channel scanning is an essential procedure to discover available access points in the vicinity and to achieve fast handover. However, this procedure leads to unnecessary overhead in wireless networks and also interrupts ongoing communications of stations. In this paper, we propose a smart proactive channel scanning scheme that allows stations to achieve fast handover with minimized communication interruptions. In the proposed scheme, periodic channel scanning is scheduled based on adaptive channel scanning intervals and activated after a frame transmission only if the mobile station is on move or the received signal strength indicator value drops below a pre-specified threshold. The proposed scheme is a client-side software solution that any station can benefit from, without changing the standard in any existing IEEE 802.11 environment. Analytical and simulation results show that the proposed channel scanning scheme reduces the channel scanning overhead dramatically, minimizes communication interruptions and improves the overall throughput of stations.