Quality-of-Service in Multihop Wireless Networks: Diffusion Approximation

TL;DR

This paper develops a channel scheduling policy for multihop wireless networks that guarantees end-to-end delay, proves network stability via fluid limits, and uses diffusion approximation to analyze performance under heavy traffic.

Contribution

It introduces a novel scheduling policy ensuring delay guarantees and provides a diffusion approximation for performance analysis in complex multihop wireless systems.

Findings

The scheduling policy guarantees end-to-end mean delay.

The network is stable under the proposed policy, proven via fluid limit analysis.

The diffusion approximation accurately models system performance under heavy traffic.

Abstract

We consider a multihop wireless system. There are multiple source-destination pairs. The data from a source may have to pass through multiple nodes. We obtain a channel scheduling policy which can guarantee end-to-end mean delay for the different traffic streams. We show the stability of the network for this policy by convergence to a fluid limit. It is intractable to obtain the stationary distribution of this network. Thus we also provide a diffusion approximation for this scheme under heavy traffic. We show that the stationary distribution of the scaled process of the network converges to that of the Brownian limit. This theoretically justifies the performance of the system. We provide simulations to verify our claims.