Comparison of bandwidth-sharing policies in a linear network

In bandwidth-sharing networks, users of various classes require service from different subsets of shared resources simultaneously. These networks have been proposed to analyze the performance of wired and wireless networks. For general arrival and service processes, we give sufficient conditions in order to compare sample-path wise the workload and the number of users under different policies in a linear bandwidth-sharing network. This allows us to compare the performance of the system under various policies in terms of stability, the mean overall delay and the weighted mean number of users. For the important family of weighted a-fair policies, we derive stability results and establish monotonicity of the weighted mean number of users with respect to the fairness parameter a and the relative weights. In order to broaden the comparison results, we investigate a heavy-traffic regime and perform numerical experiments. Keywords: bandwidth-sharing networks; sample-path comparison; alpha-fair policie