A distributed scheduling algorithm for real-time (D-SAR) industrial wireless sensor and actuator networks

Current wireless standards and protocols for industrial applications, such as WirelessHART and ISA100.11a, typically use centralized network management for communication scheduling and route establishment. However, due to their centralized nature, these protocols have difficulty coping with dynamic large-scale networks. To address this problem, we propose D-SAR, a distributed resource reservation algorithm that allows source nodes to meet the Quality-of-Service requirements for peer-to-peer communication. D-SAR uses concepts derived from circuit switching and Asynchronous Transfer Mode (ATM) networks and applies them to wireless sensor and actuator networks. Simulations show that latency in connection setup is 93% less in D-SAR compared to WirelessHART and that 89% fewer messages are sent during connection setup in case the distance from source to destination is 12 hops.