In recent decades the wireless access technologies have grown rapidly and continuously growing so leading to various different wireless technologies coexists in same geographical area. It leads to recent studies in providing the ability to mobile users to roam across these technologies in seamless manner thus providing seamless mobility. Vertical handover decision (VHD) algorithms are essential part of the architecture of Next Generation Heterogeneous Wireless networks which utilizes various parameters on which handover decision depends, like Available Bandwidth, RSS, QOS, Security, Monetary Cost etc. Our research would take RSS & QOS into consideration for making the handoff decision. These algorithms need to be designed to provide the required Received Signal Strength (RSS) & Quality of Service (QoS) to a Mobile Device for making better handoff decision [3]. In Future, different access networks like GSM/UMTS, WLAN, Wi-Fi, WiMAX, LTE Adv. will be bound together into a single network which will be glued by Internet Protocol (IP) which means service convergence in which services will be provided to users independently of their location, access technology and type of device. To fulfill this vision, we have to develop sophisticated policies for vertical handovers in which performance of mobile services will be determined by efficient and reliable vertical handoff algorithms.

Keywords : Algorithms, RSS, QOS, SINR, Vertical Hand off Decision.