A Metric for DISH Networks: Analysis, Implications, and Applications

TL;DR

This paper introduces a theoretical metric for cooperation in DISH networks, analyzes its behavior, and demonstrates its usefulness as a performance indicator and in optimizing bandwidth allocation.

Contribution

It provides the first theoretical analysis of cooperation probability in DISH networks and links it to key network performance metrics.

Findings

Cooperation probability $p_{co}$ correlates linearly with collision rate, delay, and throughput.

The analysis accurately predicts $p_{co}$ based on network parameters.

Optimal bandwidth allocation schemes are derived using the cooperation metric.

Abstract

In wireless networks, node cooperation has been exploited as a data relaying mechanism for decades. However, the wireless channel allows for much richer interaction among nodes. In particular, Distributed Information SHaring (DISH) represents a new improvement to multi-channel MAC protocol design by using a cooperative element at the control plane. In this approach, nodes exchange control information to make up for other nodes' insufficient knowledge about the environment, and thereby aid in their decision making. To date, what is lacking is a theoretical understanding of DISH. In this paper, we view cooperation as a network resource and evaluate the availability of cooperation, $p_{co}$. We first analyze $p_{co}$ in the context of a multi-channel multi-hop wireless network, and then perform simulations which show that the analysis accurately characterizes $p_{co}$ as a function of underlying network parameters. Next, we investigate the correlation between $p_{co}$ and network metrics such as collision rate, packet delay, and throughput. We find a near-linear relationship between $p_{co}$ and the metrics, which suggests that $p_{co}$ can be used as an appropriate performance indicator itself. Finally, we apply our analysis to solving a channel bandwidth allocation problem, where we derive optimal schemes and provide general guidelines on bandwidth allocation for DISH networks.