Collectively optimal routing for congested traffic limited by link capacity

TL;DR

This paper demonstrates that optimizing route choices to minimize the maximum betweenness-to-capacity ratio in a city street network can significantly reduce congestion and travel times, especially when using a mix of link capacities.

Contribution

It introduces a method for collectively optimizing routing in complex networks by minimizing the maximum betweenness-to-capacity ratio, considering heterogeneous link capacities and loads.

Findings

Traffic congestion and travel times are significantly reduced.

Using slower, smaller capacity links can improve overall network performance.

Optimization is effective in heterogeneous networks.

Abstract

We show that the capacity of a complex network that models a city street grid to support congested traffic can be optimized by using routes that collectively minimize the maximum ratio of betweenness to capacity in any link. Networks with a heterogeneous distribution of link capacities and with a heterogeneous transport load are considered. We find that overall traffic congestion and average travel times can be significantly reduced by a judicious use of slower, smaller capacity links.