A peer-to-peer discovery protocol for Semantic Web Services in industrial embedded controllers

One of the significant challenges for current and future manufacturing systems is that of providing rapid reconfigurability in order to evolve and adapt to mass customization. Service-Oriented Architecture has been proposed as a technology facilitator to create systems by encapsulating, composing and reconfiguring machines and devices rather than reprogramming the hard code. The SOA paradigm holds the promise of being applicable across the entire spectrum of manufacturing systems and devices, down to sensors and actuators. One of the pillars of SOA is the mechanism by which service advertisements are published by providers and subsequently discovered and selected by requestors. This paper presents a protocol for the dynamic discovery of services in industrial environments. The protocol is designed for operation in embedded industrial controllers, and operates in a peer-to-peer topology without a need for centralized service registries. Furthermore, the protocol enables conveying information regarding services that are semantically interoperable but that use different invocation syntax. In order to infer such semantic relationships between services, the OWLS Semantic Web Services Ontology is used. The protocol was deployed in embedded industrial controllers in order to facilitate the reconfiguration of assembly systems that employ CAALX standards for communications.