Seamless Vertical Handoff algorithm for WWANs and WLANs overlay networks

In Heterogeneous Wireless Networks (HWN), providing seamless connectivity is one of the key issues. To achieve this, an efficient vertical handoff algorithm has to be designed, which takes an account of network condition detection in terms of Quality of Service (QoS) parameters to choose the better network to maintain connectivity. This paper proposes a Seamless Vertical Handoff Decision algorithm (SVHD) which makes mobile users to access variety of services without any service degradation or interruption among overlay networks namely Wireless Wide Area Networks (WWANs) and Wireless Local Area Networks (WLANs). Simulation results show that the proposed algorithm reduces the delay and the number of packets dropped during handover.