Implementing Business Logic on Sensor Nodes

Wireless sensor networks (WSNs) will be able to assist in- dustrial and business processes and to render rich function- ality in a dependable way. Two key elements that can make this real are: a simple and efficient way of expressing the business logic, and a reliable mechanism for selectively re- configuring sensor nodes. We present a solution that com- bines both elements. The main objective is to guarantee the dissemination of business rules to multicast groups of sen- sor nodes, while striving for energy efficiency and low over- head. Simple cross-layer optimizations are used to achieve this. For scalability reasons, our solution demands only local knowledge, performs local retransmission of lost packets and uses aggregation of acknowledgements. The results of our experimental evaluation indicate a good ability of recovering from serious errors, even under high error rates.