How do network operators maintain "fairness" in their networks in the face of selfish behaivor? Although this article concerns some of the "smart routing" products, we see the same thing with other applications (and even malicious applications like worms). Every 5 years or so we discuss the need for something like a "penalty box" for ill behaived traffic. But in the end, that's too hard. Its easier to add capacity than to solve the fairness problem. http://www.nytimes.com/2003/04/24/technology/circuits/24next.html Like motorists who cut off other cars as they swerve onto residential streets to speed their own trips, an Internet based on what Dr. Roughgarden and Dr. Tardos call "selfish routing" might indeed speed up the journeys of some data packets. But over all, the two researchers found, the result is quite different. Those shortcuts through side streets often have the effect of delaying other drivers, or in the Internet's case, packets. [...] One antidote to selfish routing, the two researchers found, is more capacity. Optimum overall system speeds can be restored despite selfish routing by either doubling the number of lanes on a highway or doubling the bandwidth of a communications link. Particularly in the case of roads, however, that is rarely practical or even desirable.