Aspects of Wardrop Equilibria

Wardrop introduced his game-theoretic model in the 1950s for describing resource sharing problems in the context of road traffic systems. Nowadays, it is mainly used to model digital traffic in communication networks. A common interpretation of the Wardrop model is that an infinite number of agents is responsible to route an infinitesimal amount of traffic through a network. Each agent chooses one path from its origin to its destination, where the agent's disutility is the sum of traffic dependent edge latencies on this path. A solution concept for this game is provided by the theory of Wardrop equilibria. The primary goal of this book is to provide a deeper understanding of Wardrop equilibria. We identify several problems whose solution captures the essence of Wardrop equilibria. First, we study natural and innovative means to reduce the price of anarchy. Secondly, we analyze the stability of equilibria regarding modifications of the network environment. Finally, we propose a distributed algorithm for computing approximate equilibria.