Departmental Papers (ESE)


Traffic engineering is aimed at distributing traffic so as to "optimize" a given performance criterion. The ability to carry out such an optimal distribution depends on the routing protocol and the forwarding mechanisms in use in the network. In IP networks running the OSPF or IS-IS protocols, routing is along shortest paths, and forwarding mechanisms are constrained to distributing traffic "uniformly" over equal cost shortest paths. These constraints often make achieving an optimal distribution of traffic impossible. In this paper, we propose and evaluate an approach that is capable of realizing near optimal traffic distribution without any change to existing routing protocols and forwarding mechanisms. In addition, we explore the trade-off that exists between performance and the overhead associated with the additional configuration steps that our solution requires. The paper's contributions are in formulating and evaluating an approach to traffic engineering for existing IP networks that achieves performance levels comparable to that offered when deploying other forwarding technologies such as MPLS.

Document Type

Journal Article

Date of this Version

April 2005


Copyright 2005 IEEE. Reprinted from IEEE/ACM Transactions on Networking, Volume 13, Issue 2, April 2005, pages 234-247.

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Networks, Routing, Traffic Engineering, Aggregation



Date Posted: 26 July 2005

This document has been peer reviewed.