This paper is about how to do traffic engineering in a multipath network, so that traffic can be splitted to different paths and in the same time, change the splitting ratio to adapt to network utilization levels.
We assume the network has multipath and the different path from between two edge routers are known. This paper than proposes the TeXCP protocol for distributed traffic engineering (TE) so that load can be balanced across different paths. TeXCP tries to minimize the maximum link utilization in the network.
TeXCP is supplied with a set of paths, configured by the ISP and pined with reservation protocols like RSVP-TE. Then TeXCP pick the shortest K paths and distribute traffic among them. It sends periodic probe packet from an edge to another edge across all different paths. The probe packet contains a link utilization field which is overwritten by the routers and echoed by the end point of the path. The echoed probe tells the sending edge router the highest utilization on the path. Then, TeXCP periodically runs load balancer to adjust the load share, so that the maximum load among different paths can be lowered after the adjustment.
To avoid oscillation, TeXCP adopts the approach similar to XCP, that the router supplies positive and negative feedback for load changes, so that multiple TeXCP agents can be coordinated in catching the bandwidth share.
title = "Walking the Tightrope: Responsive Yet Stable Traffic Engineering",
author = "Srikanth Kandula and Dina Katabi and Bruce Davie and Anna Charny",
booktitle = "Proc. SIGCOMM'05",
month = "August 21-26",
year = "2005",
address = "Philadelphia, Pennsylvania, USA",