An Optimization Framework for Heterogeneous Access Management

This paper studies the problem of admission control and air interface selection in heterogeneous network environments. The statistics of random user arrivals and random service durations are considered for the optimization of heterogeneous access management strategies with respect to minimizing the expected mean cost for denial-of-service events. Based on state aggregation in a semi-Markov decision process formulation, an efficient approximation algorithm for policy optimization is proposed. Though this solution is suboptimal, it still offers considerable performance gains in comparison to simpler heuristic strategies, which is demonstrated by simulations in a heterogeneous GSM-EDGE/UMTS scenario.