On the Throughput Comparisons of MAC Protocols in Multi-Hop Wireless Networks

We revisit the use of throughput metrics in studying Medium Access Control (MAC) protocols in static multi-hop wireless networks. To complement existing single-hop and multi-hop throughput notions, we first propose a unified normalized throughput expression. Since current multi-hop metrics do not give much intuition on how close a MAC protocol's throughput performance is to the best achievable for a given network topology, we present a new variant that benchmarks against the maximum achievable throughput. It can be characterized by the product of the number of maximum successful simultaneous transmissions smax under saturated traffic conditions, and link rate R. We show how to compute smax via a linear programming formulation and demonstrate its use in both string and grid topologies. We also derive exact mathematical expressions for the maximum simultaneous transmissions for these two topologies.