A Low Latency Handoff Scheme In Heterogeneous Wireless Network

As the development of wireless communication technology, various wireless networks have been applied. Heterogeneous networks will be dominant in the next generation wireless networks. Providing a seamless handoff and quality of service (QoS) guarantees is one of the key issues in real-time services. Several mobility IPv6 schemes have been proposed and can provide uninterrupted service. However, these schemes can not handle all scenarios. This paper presents a horizontal handoff scheme that reduces the horizontal handoff latency based on the location and movement pattern of a Mobile Node (MN) and a vertical handoff scheme for providing seamless services between Wi-Fi and WiMAX networks. In homogeneous networks an MN can detect its movement actively and forecast the handoff, which alleviates the communication cost between the MN and its Access Point (AP). Furthermore, by setting the dynamic interval in an appropriate range, the MN's burden can also be alleviated. In heterogeneous networks, the vertical handoff scheme uses the velocity to be an important metric to trigger handoff. And the scheme classifies the 802.11 AP into blacklist and whitelist. The scheme can avoid unnecessary vertical handoff. Finally, by performance evaluation using computer simulations, this paper shows that the proposed scheme can lower the handoff latency efficiently.