Landmark-Based End-to-End Bandwidth Inference

The end-to-end delay among a set of peers can be easily and scalably estimated using a landmark approach Peers´ coordinates are deduced from delay measurements to a small number N of landmarks L{L1,..., Ln}. We wonder whether it is feasible to use such distributed solution for bandwidth estimation. This requires that each peer determines its bandwidth vector by measuring the direct and reverse bandwidth on its path with each landmark. The bandwidth vectors of two peers are then used to estimate the bandwidth between them in both ways. For a couple of peers, we denote by (i) direct path the network path that joins them directly using IP routing, and by (ii) indirect path the path that joins them via a landmark node. N indirect paths (N being the number of landmarks) are assigned to each direct path. Our idea is to estimate the bandwidth of the direct path using those of the indirect paths. The indirect paths that have more links common with the direct path, are assigned more weight in the estimation function. We consider different estimation functions and we study the impact of the landmarks´ locations on the accuracy of the estimations.