At present, freely deployed wireless access technologies, most notably the IEEE 802.11 family (a.k.a. WiFi), do not support any reliable means to determine the real achievable bit-rate over the link between a wireless terminal (STA) and an access point (AP), or between two terminal stations. This is due to fact that conventional AP beacons broadcast only their bit-rate technical capability, not real estimations of what could be achieved in the particular environment taking into account signal quality and current congestion levels. As a result, the information used by a STA to connect to an AP is inaccurate and incomplete.
This limitation in the art poses problems for WiFi users, for many end-user applications require information on the real achievable bit-rate before making a decision of which access point to associate when multiple access points are available. Conventional WiFi technology provides information regarding signal quality to assist in the determination of the estimated bit-rates; however, the conventional bandwidth (bit-rate) estimators, such as Pathcar, require build up of the full connection (i.e., a full association in the WiFi network between AP and STA and an IP connection over the created link) in order to probe by using network packets. As a result, such methods require a substantial amount of latency and overhead and, most importantly, such techniques are not applicable to a determining which AP to build up a connection to in the first place. The future 802.11k extension promises to provide some two-way signal strength information also from the AP to the STA, including history information, but not real bit-rate estimation.
In view of the needs in the art for improved bit-rate estimation prior to making WiFi connections between STAs and APs, a simple method is desired to better estimate the download bit-rate between a STA and an AP that takes into account the congestion on the corresponding AP as well as the signal quality. A system and method for achieving congestion load balancing when multiple APs are available, thus ensuring the best download bit-rate to wireless stations, is also desired. The present invention addresses these needs in the art.