A novel inter-system handoff scheme in wireless overlay networks

The wireless overlay network will play an important role in future mobile communications and Internet access. It will be an IP-based network, which includes various wireless access methods and provides all kinds of services such as voice, data and multimedia. Handoff is a critical issue of the wireless overlay network, because it can guarantee seamless roaming among different networks. Based on a WLAN-GPRS wireless overlay network model, and considering channel characteristics, service types and factors influencing the handoff process, a novel inter-system handoff scheme is proposed and relative decision benchmarks are discussed. Simulations on the key parameters, such as throughput, packet loss and handoff delay, prove that the proposed handoff scheme can provide powerful support for seamless handoff and continuous communication.