Integration of OPC Unified Architecture with IIoT Communication Protocols in an Arrowhead Translator

Abstract: This thesis details the design of a protocol translator between the industrial-automation protocol OPC UA, and HTTP. The design is based on the architecture of the protocol translator of the Arrowhead framework, and is interoperable with all of its associated protocols. The design requirements are defined to comply with a service-oriented architecture (SOA) and RESTful interaction through HTTP, with minimal requirement of the consuming client to be familiar with OPC UA semantics. Effort is put into making translation as transparent as possible, but limits the scope of this work to exclude a complete semantic translation. The solution presented in this thesis satisfies structural- and foundational interoperability, and bridges interaction to be independent of OPC UA services. The resulting translator is capable of accessing the content of any OPC UA server with simple HTTP-requests, where addressing is oriented around OPC UA nodes.