: Handoff at the link layer 2 (L2) consists of three phases including scanning, authentication, and reassociation. Among the three phases, scanning is dominant in terms of time delay. Thus, in this paper, we propose an improved scanning mechanism to minimize the disconnected time while a wireless station (STA) changes the associated access points (APs). According to IEEE 802.11, an STA has to scan all channels in scanning. In this paper, based on the neighbor graph (NG), we introduce a selective channel scanning method with unicast for fast handoff in which an STA scans only channels selected by the NG. Experimental results show that the proposed method reduce the scanning delay drastically.