Abstract:

The performance of IP flows in Wireless Mesh Networks is unfairly biased by the unplanned compounding behavior of MAC and transport protocols. This compounding protocol behavior can undesirably result in complete starvation of some flows and in consistent capacity reductions originated by, e.g., limited volumes of control traffic.

This talk will show, via analysis and real experiments over operational mesh networks, the origins of unfairness between IP flows in the framework of 802.11-based mesh networks. A spatial biasing effect will be shown and modeled, which severely reduces the network throughput when multiple data and control flows are competing for accessing a shared wireless media.

In the talk, two mechanisms will be discussed as possible solutions to counteract unfairness and throughput reduction. The first solution exploits a simple and static modification in the 802.11 contention window.

The second solution uses a dynamic rate limiting approach exploiting the root causes of flow unfairness to enforce a distributed and effective rate control scheme. Both solutions successfully solve the starvation problem, allow to design a network-wide rate control policy, and are easy to implement over off-the-shelf 802.11 devices

Talk followed by a Q&A Session.

The conference will be conducted in English