Altruism and selfishness in traffic routing. The

One of the most basic and important problems in managing networks is to route traffic so as to make the latency ex-perienced by the average user small. This problem can be solved effectively when all the traffic submits to the control of a central authority. However, neither in road networks nor in large-scale decentralized computer networks (such as the Internet) is it feasible to establish such a central author-ity. Rather, individual users of the network have control over the paths they choose from their origin to their desti-nation. The prevailing assumption is that users will exert this power to choose the route minimizing their individual latency, regardless of the effects that such a choice may have on other users. A natural question is then how much the average latency increases as a result of such selfish behavior, compared to