Intelligent Vertical Handoffs between Heterogeneous Communication Networks

1IntroductionWith the increasing demand for mobile access ,theInternet has to provide not only li mited mobility,suchas WLAN1 ~3]access ,but also worldwide mobility,asexemplified by Mobile IP4 ~7]to meet the user require-ments in terms of data rate and mobility.In particular ,it is desired that when a user stays in the hotspot cov-ered by WLAN, he can access the Internet throughWLAN,and when he goes out of the hotspot ,the on-going connection should not be dropped,but is insteadhanded …

Intelligent Vertical Handoffs between Heterogeneous Communication Networks

This paper proposes an intelligent vertical handoff algorithm to maintain an ongoing call between a cellular mobile network and a Wireless Local Area Network (WLAN), based on the Received Signal Strength (RSS) threshold and an adaptive RSS hysteresis generated by fuzzy logic. In addition, the proposed algorithm accounts for the WLAN traffic loading and the direction of movement and speed of the Mobile Station (MS). Simulation results indicate that the proposed algorithm offers better system performance in terms of number of handoffs and probability of call dropping.