Energy efficient multi-channel media access control for dense wireless ad hoc and sensor networks

Traditional single-channel MAC protocols for wireless ad hoc and sensor networks favor energy-efficiency over throughput. More recent multi-channel MAC protocols display higher throughput but less energy efficiency. In this article we propose NAMAC, a negotiator-based multi-channel MAC protocol in which specially designated nodes called negotiators maintain the sleeping and communication schedules of nodes within their communication ranges in static wireless ad hoc and sensor networks. Negotiators facilitate the assignation of channels and coordination of communications windows, thus allowing individual nodes to sleep and save energy. We formally define the problem of finding the optimal set of negotiators (i.e., minimizing the number of selected negotiators while maximizing the coverage of the negotiators) and prove that the problem is NP-Complete. Accordingly, we propose a greedy negotiator-election algorithm as part of NAMAC. In addition, we prove the correctness of NAMAC through a rigorous model checking and analyze various characteristics of NAMAC—the throughput of NAMAC, impact of negotiators on network capacity, and storage and computational overhead. Simulation results show that NAMAC, at high network loads, consumes 36 % less energy while providing 25 % more throughput than comparable state-of-art multi-channel MAC protocols for ad hoc networks. Additionally, we propose a lightweight version of NAMAC and show that it outperforms (55 % higher throughput with 36 % less energy) state-of-art MAC protocols for wireless sensor networks.