Communication Bottlenecks in Scale-Free Networks

TL;DR

This paper investigates how network topology influences packet routing efficiency, establishing universal bounds on network capacity and proposing a new routing protocol that outperforms shortest path routing in scale-free networks.

Contribution

It introduces a universal upper bound on network capacity based on vertex separators and proposes a novel static routing protocol optimized for scale-free networks.

Findings

Universal upper bound on packet insertion rate $$ based on network topology.

The proposed static routing protocol outperforms shortest path routing under high load.

Derived capacity estimates for scale-free networks.

Abstract

We consider the effects of network topology on the optimality of packet routing quantified by $\gamma_c$, the rate of packet insertion beyond which congestion and queue growth occurs. The key result of this paper is to show that for any network, there exists an absolute upper bound, expressed in terms of vertex separators, for the scaling of $\gamma_c$ with network size $N$, irrespective of the routing algorithm used. We then derive an estimate to this upper bound for scale-free networks, and introduce a novel static routing protocol which is superior to shortest path routing under intense packet insertion rates.