A MAC protocol for Delay-Bounded applications in Wireless Sensor Networks

The problem of scheduling packet transmissions for data gathering in wireless sensor networks is studied in this paper. A scenario is considered where different sources contemporarily sense an event and signal the acquired information to a sink. Energy-latency tradeoffs for data gathering in sensor networks are explored by means of Integer Linear Programming Formulations. The objective of the optimization problems defined is to find minimum latency and minimum energy optimal data delivery trees, which are defined as aggregates of flows from multiple sources to a single receiver. A new distributed MAC protocol explicitly designed for Delay-Bounded Applications in Wireless Sensor Networks (DB-MAC) is also introduced. The primary objective of DB-MAC is to minimize the latency for delay bounded applications. Energy consumption is also reduced by means of a path aggregation mechanism that improves path sharing. Simulation results show that DB-MAC reduces the latency up to 70% with respect to a CSMA/CA MAC protocol, with up to 60% less transmissions. The performance of DBMAC is shown to be closer than CSMA/CA to the optimal values of latency and energy consumption.