On the benefits of time-varying routing in realistic mobile backhaul networks

Since traffic load in mobile networks typically changes significantly over time, time-varying routing, where routing changes in certain time intervals, seems an obvious solution. Yet multiple researchers have claimed independently in the past, that time-varying routing does not lead to worthwhile benefits given its overhead. In this paper, we study this issue in a systematic way. We argue that previous claims are due to focusing on too narrow optimization metrics and demonstrate the poor expressiveness of such metrics using real mobile backhaul topologies. We propose a novel traffic engineering metric, capacity variation, and on that basis, prove that time-varying routing can in fact have great benefits, particularly in terms of infrastructure CAPEX costs. A quantitative evaluation on the benefits is provided based on real mobile backhaul data from a European operators.