End-to-end fair rate optimization in wired-cum-wireless networks
In this paper, we address the end-to-end rate optimization problem in a wired-cum-wireless network, where CSMA/CA based wireless LANs extend a wired backbone and provide access to mobile users. The objective is to achieve proportional fairness amongst the end-to-end sessions in the network. Since the network contains wireless links whose attainable throughput is a (non-convex and non-separable) function of MAC protocol parameters, the problem requires joint optimization at both the transport and the link layers. A dual-based algorithm is proposed in this paper to solve this cross-layer rate optimization problem. It is implemented in the distributed manner, and works at the link layer to adjust scheduling rates for the wireless links in the basic service sets, and at the transport layer to adjust end-to-end session rates. We prove rigorously that the proposed algorithm converges to the globally optimal rates. Simulation results are provided to support our conclusions.
© 2008 Elsevier B.V. Received 6 August 2007; revised 16 March 2008; accepted 27 May 2008. Available online 8 June 2008. This work was supported by the National Science Foundation through grants CNS-0435141 and CNS-0448316. This is an extended version of a paper that appeared in the International Teletraffic Congress (ITC), Beijing, China, August 2005.