15-02-2014, 12:01 PM
We have shown that when nodes are equipped with multiple heterogenous radios, it is important to select channeldiverse paths in addition to accounting for the loss rate and bandwidth of individual links. We have implemented a routing protocol MR-LQSR (Multi-Radio Link-Quality Source Routing) with a new metric WCETT (Weighted Cumulative Expected Transmission Time) to accomplish this task, and compared its performance to other routing metrics in a multi-radio testbed. Our results show that WCETT outperforms previously-proposed metrics. WCETT allows us to trade off channel diversity and path length, by changing the value of the control parameter β. We experimented with different values of this control parameter, and showed that on shorter paths, taking channel diversity into account brings significant benefits. We also showed that on longer paths, as well as in heavily-loaded networks, the benefits obtained by selecting channel-diverse paths are limited. In the future, we plan to expand our testbed by adding more nodes. This will allow us to better explore the performance of WCETT for multiple simultaneous transfers. We also plan to investigate whether with different hardware, we hope to investigate the performance of WCETT in mobile scenarios.