Potential Game in a Parallel Transportation Network with Symmetric Externalities

A model of a transportation system with parallel channels and BPR latency functions with symmetric linear externalities is considered in the case where the impact of the channel loads on latency is pairwise symmetric. For this case, it is proved that the game of traffic allocation among the channels is potential, and the price of anarchy is bounded above by a value of $$\frac{4}{3}$$ .