Optimization of vertical handoff in UMTS_WLAN heterogeneous networks

Seamless mobility is an important and challenging issue to guarantee required Quality of Service (QoS) in Next Generation Wireless Network (NGWN). In this paper, we have proposed a technique to support seamless mobility in optimized time with best utilization of network resources in heterogeneous network of UMTS (Universal Mobile Telecommunication System) and WLAN. Vertical handoff is analyzed to provide adaptive handoff trigger time for vertical handoff decision algorithm. Since performance of a wireless network depends upon accurate trigger timing of handoff, the proposed technique reduces the network load by minimizing link failure and maximizes the resource utilization and subsequently improves the system performance.