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

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 multichannel 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 multichannel multihop 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.