AmbientRT - real time system software support for data centric sensor networks

We present the architecture and design of a real time operating system for mobile wireless sensor networks. AmbientRT is being developed for environments with very limited resources in order to relieve the burden of the developer and to use the resources of the node efficiently. The paper presents the main concepts used and the trade-offs involved in the system. Initial results show that with the current hardware available for sensor networks, the real time concept is feasible. For real-time scheduling, we have designed EDFI. EDFI is a lightweight real-time scheduling protocol that combines EDF (earliest deadline first) with deadline inheritance over shared resources. EDFI is precise with task admission control, very efficient with scheduling and dispatching, and straightforward in feasibility analysis.

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