End-to-end throughput and delay analysis of WiFi multi-hop network with deterministic offered load

In a wireless multi-hop or mesh network, stations which are connected to Mesh Access Point (MAP) lesser hops from the gateway are expected to enjoy higher throughput and lower delay than stations connected to the MAP further hops away. To solve this issue, we introduce a technique to determine network layer queue size limit of ingress radio interfaces in the multi-radio MAPs. The intention is to partially control the transmit probability of forwarded packets during network congestion. End-to-end throughput and delay with four types of queue configurations were measured in an experimental testbed. The results show that a delay variance reduction of 38× between the first hop and the subsequent hops can be achieved using the proposed technique with a minimal drop (<0.05Mbps) in average throughput. (6 pages)