Pre-Register Algorithm for SVC by Fast BSS Transition Wireless Networks

Recently, with the more extensive deployment of Wireless Local Area Networks (WLAN), and the growing population of mobile users, the unstable handover problem in wireless network services receives more and more attention. Since users expect the continuity of services while roaming, IEEE 802 family defines the standard IEEE 802.11r (Fast BSS Transition) to reduce the interrupted time of services to the minimum. Supposing users use IEEE 802.11r to execute the pre-authentication process with all Access Points, there will be too many authenticated messages. Therefore, an IEEE 802.11r based algorithm is proposed to avoid the pre-authentication process with all APs. In order to reduce the pre-register APs, we first of all divide the coverage of the APs into four regions according to the RSSI. Second, to figure out more accurate APs, we dynamically adjust the region. Third, if the mobile device cannot find the AP of each region, we further modify the region. Finally, we pick up an AP to execute the pre-authentication each region. With the four above-mentioned considerations proposed in this algorithm, we are able to make use of roaming more effectively.