Middleware

To realize such concepts of convergent communication, a unifying communication layer is required that addresses all connected systems via a common software interface (API). This also permits the realization of service-oriented architectures that enable loose coupling of systems. Here too, the open source community offers a wide range of so-called middleware systems like Camel, Kafka, and many others.

The ability of software systems to integrate with such middleware creates the foundation for data-consistent communication systems, as exemplified by an enterprise or manufacturing service bus.

Given the range of middleware systems now available, we must ask how one can ensure connectivity and interoperability across widely divergent systems.

Standardization plays a major role in this respect, and OPC UA is among the most important of these standards for industrial communication. Thanks to its integrated data model, OPC UA permits connectivity with a high degree of data abstraction.

Industry associations like the VDW are doing development work here. Its UMATI initiative was established to promote the data model for data exchanges in the machine tool user domain. The outcome will be a so-called OPC UA Companion Specification, i.e. a specific data model for this application domain.

Another major standardization initiative is the so-called Asset Administration Shell (AAS), which is derived from RAMI 4.0 (Reference Architecture Model Industry 4.0). The AAS aims, in future, to enable the development of systems with such a degree of integration that production processes are able to self-organize which would form the foundation of a truly Smart Factory.