How Bad is Selfish Routing?

We consider the problem of routing traffic to optimize the performance of a congested network. We are given a network, a rate of traffic between each pair of nodes, and a latency function for each edge specifying the time needed to traverse the edge given its congestion; the objective is to route traffic such that the sum of all travel times--the total latency--is minimized. In many settings, it may be expensive or impossible to regulate network traffic so as to implement an optimal assignment of routes. In the absence of regulation by some central authority, we assume that each network user routes its traffic on the minimumlatency path available to it, given the network congestion caused by the other users. In general such a "selfishly motivated" assignment of traffic to paths will not minimize the total latency; hence, this lack of regulation carries the cost of decreased network performance. In this paper we quantify the degradation in network performance due to unregulat...

• Type: Conference
• Year: 2000
• Where: FOCS
• Authors: Tim Roughgarden, Éva Tardos
• Keywords: FOCS 2000, Latency Functions, Possible Total Latency, Theoretical Computer Science, Total Latency