Performance evaluation of the anypath routing and forwarding mechanism AP-OLSR

Wireless mesh networks (WMNs) consist of several small routers relaying packets wirelessly toward the destination or the Internet. A dense deployment enables the rapid creation of wireless access networks at a reasonable cost. The capacity of a wireless mesh network can be increased by using a diverse set of channels to allow simultaneous transmissions without causing interference. An interesting approach is to use one fixed wireless network interface for receiving and at least one switchable interface for sending. However, such a channel assignment suffers from switching overhead. In order to minimize the channel switching latency, we have developed a novel packet routing and forwarding strategy, AP-OLSR, which uses multiple next hop candidates tuned to different channels. When forwarding a packet, nodes pick the neighbor which is on a channel that gives a good balance between local switching overhead and global path quality. In this paper, we present a thorough evaluation of AP-OLSR with scenarios involving both single and multiple gateways, as well as single and competing flows. The evaluation shows that AP-OLSR can improve performance in both latency and throughput.