Optimum network selection in heterogeneous wireless environment using gravitational search algorithm

In recent years, the growth in user demand and diversity of real time services has lead to the integration of different wireless technologies. Cellular technologies can provide data services over a wide area, but with lower data rates. Wireless Local Area Network (WLAN) technologies offer higher data rates, but over smaller hotspots. The demand for ubiquitous data service can be fulfilled, if it is possible for the end-user to seamlessly roam between these heterogeneous technologies. In an environment of wireless networks with different standards, choosing an optimum network to handoff the ongoing service plays a crucial role. An efficient network selection algorithm using different network metrics is developed in this paper for performing vertical handoff decision function. Dynamic weights assigned to these metrics are optimized using Gravitational Search Algorithm (GSA). The network with highest handoff decision value is qualified as the optimum network for handoff execution resulting in better Quality of Service (QOS).