In 2015, the IIC released the Industrial Internet Reference Architecture (IIRA) for IIoT systems (IIC-IIRA). It uses "ISO/IEC/IEEE 42010:2011 Systems and Software Engineering–Architecture Description" for architectural conventions and common practices. IIRA provides an architectural framework to analyze concerns, views, models, and so on with certain degrees of abstraction. The use of reference architectures helps to incorporate security by design. Architects can build use case-specific IIoT architectures on top of these reference architectures.
In this section, the four viewpoints of IIC's reference architecture are briefly discussed. These viewpoints simplify the understanding and decomposition of IIoT architectures. You can find an in-depth treatment of these viewpoints in (IIC-IIRA).