Fast Handoff Algorithm Using Access Points with Dual RF Modules
With the spread of portable computers, mobile users rapidly increase and have growing interests in wireless LAN (WLAN). However, when a mobile node (MN) moves, handoff can frequently occur. The frequent handoff makes fast and seamless mobility difficult to achieve. Generally the handoff delay is so long that a provider can not support realtime services sufficiently. In this paper, to address the link layer (L2) handoff delay problem, we propose a fast handoff algorithm using access points (APs) with dual radio frequency (RF) modules. The proposed handoff algorithm is based on the modified neighbor graph (NG). Experimental results show that the proposed method reduces the L2 handoff delay drastically. Furthermore, the handoff delay in the network layer (L3) can be also reduced simultaneously, since the proposed algorithm can support L2 triggers.
KeywordsMobile Node Medium Access Control Access Point Receive Signal Strength Indication Neighbor Graph
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