A Vertical Handoff Decision Algorithm for Next Generation Wireless Networks

The integration of diverse but complementary cellular and wireless technologies in the next generation wireless networks requires the design of intelligent vertical handoff decision algorithms to enable mobile users equipped with contemporary multi-interfaced mobile terminals to seamlessly switch network access and experience uninterrupted service continuity anywhere and anytime. This paper provides an adaptive multiple attribute vertical handoff decision algorithm that enables wireless access network selection at a mobile terminal using fuzzy logic concepts and a genetic algorithm. A performance study using the integration of universal mobile telecommunications system (UMTS) and world-wide interoperability for microwave access (WiMAX) as an example shows that our proposed vertical handoff decision algorithm is able to determine when a handoff is required, and selects the best access network that is optimised to network conditions, quality of service requirements, mobile terminal conditions, user preferences, and service cost.