Date Added: Feb 2010
Vertical Handover Decision (VHD) algorithms are essential components of the architecture of the forthcoming Fourth Generation (4G) heterogeneous wireless networks. These algorithms need to be designed to provide the required Quality of Service (QoS) to a wide range of applications while allowing seamless roaming among a multitude of access network technologies. In this paper, the authors present a comprehensive survey of the VHD algorithms designed to satisfy these requirements. To offer a systematic comparison, they categorize the algorithms into four groups based on the main handover decision criterion used. Also, to evaluate tradeoffs between their complexity of implementation and efficiency, they discuss three representative VHD algorithms in each group.