Automac: Rateless Wireless Concurrent Medium Access

Current wireless network design is built on the ethos of avoiding interference. In this paper we question this long-held design principle. We show that with appropriate design, successful concurrent transmissions can be enabled and exploited on both the uplink and downlink. We show that this counter-intuitive approach of encouraging interference can be exploited to increase network capacity significantly and simplify network design. We design and implement AutoMAC, a novel MAC and PHY protocol that exploits recently proposed rateless coding techniques to provide such concurrency. We show via a prototype implementation and experimental evaluation that AutoMAC can provide a 60% increase in network capacity on the uplink compared to traditional Wifi that does omniscient rate adaptation and a 35% median throughput gain on the downlink PHY layer as compared to an omniscient scheme that picks the best conventional bitrate.