Next generation wireless network is envisioned as a convergence of different wireless access technologies

providing the user enhanced connection any where any time to improve the systems resource utilization. It

is likely that WLAN/HIPERLAN will become an important complementary technology to cellular

networks and typically used to provide hotspot coverage where there is a high density of users. In such

converged systems, co-existence of heterogeneous access technologies with largely different characteristics

like data rate for cellular network (2 Mbps), WLAN 802.11b (11 Mbps) and HIPERLAN (54 Mbps) results

in handoff asymmetry that differs from the traditional intra-network handoff (horizontal handoff).