One of major objectives of the fourth generation wireless network architecture is to facilitate seamless mobility of users between heterogeneous networks while satisfying QoS requirements. Vertical handover decision (VHD) algorithms are essential components of the architecture of the 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 large number of access network technologies. In this paper, we present a comprehensive study of the VHD algorithms designed to satisfy these requirements

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Handover Vertical Handover Vhd Algorithms Qos