OppoScan: Enabling Fast Handoff in Dense 802.11 WMNs via Opportunistic Probing with Virtual Radio

Recently with the sharing economy of WiFi, IEEE 802.11 Wireless Mesh Networks (WMNs) have been deployed exponentially in more places. With the booming increase of density of APs as well as mobile clients (MCs), the handoff between MCs and APs becomes more frequent than ever before. One problem of most existing network-assisted fast handoff mechanisms is that an AP needs to switch to different channel to probe MCs, thus disrupting its current communications. In this paper, we propose a fast handoff mechanism called OppoScan. OppoScan opportunistically leverages nearby MCs and APs to produce the required information of neighboring AP for handoff, thus significantly decrease the number of switching channel of APs. We have implemented the OppoScan in about 200 APs in two shopping malls and the results demonstrated the performance of the proposed scheme.