Design and implementation of a multi-channel multi-interface network

The use of multiple wireless channels has been advocated as one approach for enhancing network capacity. In many scenarios, hosts will be equipped with fewer radio interfaces than available channels. Under these scenarios, several protocols, which require interfaces to switch frequently, have been proposed. However, implementing protocols which require frequent interface switching in existing operating systems is non-trivial. In this paper, we identify the features needed in the operating system kernel for supporting frequent interface switching. We present a new channel abstraction module to support frequent interface switching. We identify modifications to interface device driver to reduce switching delay. The channel abstraction module, and an example multi-channel protocol that uses the module, have been implemented in a multi-channel multi-interface testbed. We also present results to quantify the overheads of frequent switching