Cross-layer Approach for Seamless Vertical Handover in Networks: a Cross-layer Approach for Seamless Vertical Handover in Heteronenous Overlay Networks

Future Wireless systems will be characterized by their heterogeneity. Multiple access technologies provide access to internet content. Vertical handoff is an important mechanism for achieving continuous seamless transmissions in these networks. When connections need to migrate between heterogeneous networks seamless vertical handoff is necessary. Hence seamless vertical handoff is the first step. With regard to VHO performance, there is a critical need to develop algorithms for connection management and optimal resource allocation for seamless mobility. The integration of WLAN and Wimax has attracted the most attention. In some situation where many mobile devices try to handoff to the same AP, there will be more power consumption at the mobile devices due to increased congestion delay at the AP. Here we take account of e QoS parameters, bandwidth, jitter packet error rate and end-to-end delay, which are selected from multi-layer contributions. First vertical handoff was based on received signal strength (RSS) of the mobile node. Next vertical handoff is improvised by considering bandwidth as well as RSS. Results were simulated using NS-2 and comparison results are evaluated.