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 s_max under saturated traffic conditions, and link rate R. We show how to compute s_max 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.