A mobility model for cost analysis in integrated cellular/WLANs

In this article, we propose a model that can be used to study the costs and benefits of integrating cellular and wireless LANs, from a vendor and a user perspective. We explain the model and the approach to calculate the costs for a simple handoff topology that supports a voice call across a cellular and a WLAN. The mobility model, which can be used to estimate the probability of a cellular user entering a WLAN while moving within the "location area" of the cellular network, is the main contribution of this work. The mobility model takes into account a normal user movement and a biased user movement based on a 2D random walk model. We show how this model could be used to study the costs and benefits to the vendor and the user, especially if a user were to be supported with call continuity across the two networks and the vendor had to bear the extra costs of handing over an active call. We have restricted our analysis to a scenario where the user with an active voice call moves from the cellular network to the WLAN. Graphs and discussions are provided to demonstrate the use of the model to study the integration benefits, from a vendor and a user perspective