Access Point Selection Strategy for Large-Scale Wireless Local Area Networks

This paper presents an access point (AP) selection strategy for the (re)association procedure in large-scale WLAN. The proposal considers the difference of node topology among candidate basic service sets (BSSs), wherein the effects from hidden terminals are emphasized due to its significant impact on throughput degradation. Comparing with existing mechanisms, the proposal combats load imbalance problem that the popular signal strength measurement based selection strategy may cause. Meanwhile, it estimates the BSS load status in more accurate way by differentiating hidden terminal from others, so a higher throughput is resulted. More significantly, the proposal uses the advertised information of the Beacon/Probe Response frame in IEEE 802.11e, without any hardware modification. Such back-compatibility facilitates the implementation over currently deployed WLAN. The performance is validated via simulation which shows that the proposal can achieve up to 20% throughput enhancement over existing methods particularly over the uplink.