Distributed-queue access for wireless ad hoc networks

We propose a novel MAC protocol for wireless ad hoc networks, called distributed queue dual channel (DQDC). Our protocol relies on the 802.11 DCF scheme but derives key ideas from the well-known DQDB protocol, standardized for wired MAN, and applies them to wireless networks. DQDC employs two separate channels: a control and a data channel. Our objective is to achieve 100% utilization of the data channel, minimizing the collision probability on it. DQDC is based on the following key idea: stations that overhear a transmission on the data channel set their NAV and switch to the control channel, where contention takes place through the RTS/CTS mechanism. Successful contentions are stored in a virtual, distributed queue system. Upon expiration on NAVs, stations switch to the data channel where the station at the top of the distributed queue transmits without contention. Some preliminary simulation results, obtained through ns-2, show that DQDC significantly outperforms the standard 802.11 DCF.