Ant Backpressure Routing for Wireless Multi-hop Networks with Mixed Traffic Patterns

TL;DR

This paper introduces Ant Backpressure (Ant-BP), a distributed routing scheme combining ant colony optimization with backpressure routing to improve latency and delivery ratio in wireless multi-hop networks with mixed traffic.

Contribution

It proposes a novel routing scheme that integrates multi-path routing with FIFO link sharing, addressing the last-packet problem in backpressure routing.

Findings

Ant-BP improves latency and delivery ratio over existing schemes.

Ant-BP maintains throughput comparable to SP-BP under low-to-medium loads.

Ant-BP is fully distributed and scalable.

Abstract

A mixture of streaming and short-lived traffic presents a common yet challenging scenario for Backpressure routing in wireless multi-hop networks. Although state-of-the-art shortest-path biased backpressure (SP-BP) can significantly improve the latency of backpressure routing while retaining throughput optimality, it still suffers from the last-packet problem due to its inherent per-commodity queue structure and link capacity assignment. To address this challenge, we propose Ant Backpressure (Ant-BP), a fully distributed routing scheme that incorporates the multi-path routing capability of SP-BP into ant colony optimization (ACO) routing, which allows packets of different commodities to share link capacity in a first-in-first-out (FIFO) manner. Numerical evaluations show that Ant-BP can improve the latency and delivery ratio over SP-BP and ACO routing schemes, while achieving the same throughput of SP-BP under low-to-medium traffic loads.