Reliable Data Forwarding for Delay Constraint Wireless Sensor Networks

Many applications for wireless sensor networks require immediate and guaranteed actions; data have to be transported reliably and in time through the network towards the final sink. In this work we focus our attention on the control of data transport delay and reliability in a multihop scenario. We investigate and show some trade-offs between the delay and the energy consumption required by cooperative and non cooperative ARQ techniques. In particular we describe a mathematical model to calculate the delay necessary to correctly deliver a packet to the destination (sink) through the multihop path and we give close form expressions for the delay in some particular topologies.