A Preamble Ahead Anycast Protocol for WSNs

This paper presents a novel cross-layer anycast medium access control (MAC) protocol for wireless sensor networks (WSNs) based on advanced preamble propagation and geographic routing. The protocol aims at reducing the sleep-delay problem, common in asynchronous preamble-based MAC protocols. When a packet is ready to be transmitted, differently from other state-of-the-art protocols, the preamble sequence is propagated in advance for several hops before packet release. So, a simultaneous propagation of signaling and packet is obtained. The number of nodes in the Forwarding Candidate Set (FCS) in our anycast protocol is chosen to settle the average speed of preambles to the velocity of packet propagation. In order to enablethe simultaneous transmissions without collision, a minimum distance between preambles and data packet is preserved. Simulations results showed that our protocol outperforms in latency all other asynchronous MAC protocols appraised, for all evaluated packet sizes. This result was obtained with an energy consumption similar to the other state-of-the-art protocols.