Traffic Management through Link

We propose a systematic means for achieving a set of overall traac management or planning goals with respect to the performance of the traac network through the use of link tolls. The primary goals are deened by a set of link ow restrictions. The tolls that achieve these goals are obtained by solving a generalization of the classical user equilibrium model which includes a set of side constraints on the link ows. The set of toll prices obtained is not necessarily unique; this fact enables the traac planner to choose a toll scheme which satisses exogenous constraints and which may optimize a secondary goal, such as with respect to the toll itself. The overall model is derived as a special case of a mathematical program with equilibrium constraints (MPEC) describing a Stackelberg game involving the traac manager and the users of the network. The model is shown to yield valuable information also in the case where the management goals and exogenous toll constraints are inconsistent with each other or with the underlying network. We give several examples of possible applications of the model, including the achievement of a system optimal ow and the derivation of actions for making public transport more attractive, and propose a conceptual algorithm for solving it. The paper is hoped to provoke continued research in both theoretical and applied directions.