Vertical handover triggering between WLAN and WIMAX using sip

Nowadays due to the increase in demand for various multimedia services requiring high capacity, shortage of wireless resources becomes a serious problem in cellular networks. It is difficult to suddenly increase the capacity of wireless communication networks because of high cost and complexity. In order to increase the capacity of wireless communication networks with minor changes and low cost, internetworking is needed. The main objective of SIP is to support the upper layer and mobility management protocols to optimize the handover process between heterogeneous networks such as Ethernet, Bluetooth, Wi-Fi, WiMAX, 802.11 and various other networks. The basic purpose of the SIP standard is to facilitate between heterogeneous networks to provide seamless mobility. This standard also supports handover for the both mobile as well as stationary users. For mobile users, handover can occur when wireless link condition changes due to Mobile Node (MN) movement. In this proposed work, Vertical handover is implemented between WLAN and WiMAX networks by using Session initiation protocol and the performance metrics such as Network delay, Neighbour advertisements, Handover delay and throughput were obtained.