Consensus-based algorithm for making network selection decisions in heterogeneous wireless networks

Network-selection decision for a multimode terminal having multiple classes of simultaneous handoff calls (such as file download and video session) can be made independently for the individual calls or jointly for the group of calls. Existing radio access technology (RAT) selection algorithms developed for making network-selection decisions for singles calls are not suitable for making network-selection-decisions for multiple calls. Therefore, this paper proposes an algorithm that makes network-selection decisions for multiple calls based on consensus level among the multiple calls to be admitted in a heterogeneous wireless network. The proposed algorithm considers individual user's preferences and the quality of service required by individual calls in making RAT-selection decisions. When the consensus level among multiple calls to be admitted into a particular RAT is high, the multiple calls are jointly admitted into a single RAT. However, when the consensus level among the multiple calls to be admitted is below a predefined threshold, the multiple calls are independently admitted into suitable RAT(s). The performance of the proposed RAT selection scheme is evaluated in a three-service three-RAT heterogeneous network, supporting multi-homed terminals. Simulation results are given to show the effectiveness of the proposed scheme.