A survey on OPC and OPC-UA: About the standard, developments and investigations

In 1996, a new standard was announced that should serve as a software interface to exchange process data and to solve the problem to exchange process data using different industrial protocols and communication systems. A successful story started since then with few additional standards like the Alarm and Event standard using the OPC approach and some revisions and new editions. Ten years later a new approach was created that unified all existing standards and was also concerned with e.g. interoperability, security and web-based systems. This paper details the different OPC standards, tries to answer the question why this standard is important for industries and academia and where current research and development utilising those standards.