Design of IGP link weight changes for estimation of traffic matrices

Abstract

We consider the traffic matrix estimation problem in IP backbone networks, whose goal is to accurately estimate the volume of traffic traveling between network endpoints. Previous approaches to this problem involve measuring the volume of traffic on each link in the network during a time interval where the routing configuration is fixed, and exploit a statistical model of the traffic in order to obtain an estimate of the traffic matrix. These previous approaches are prone to large estimation errors because the link measurements from a fixed muting scenario constitute a data set that is simply too limited to provide enough data to enable estimation procedures that yield very small errors. We propose the idea of collecting link measurements under multiple routing scenarios so that the traffic matrix can be determined very accurately. We present an algorithm for determining a sequence of routing configurations, each of which is specified by a set of link weights. We incorporate carrier requirements into our algorithm so that our proposed routing configurations are operationally viable. We present the results of applying our algorithm to some representative IP backbone topologies and discuss the performance trade-offs that arise.