Version 1.8 of the IIC’s Industrial Internet Reference Architecture Introduces New and Substantive Ideas

The Industrial Internet of Things (IIoT) core ideas and technologies are broadly applicable to and expected to have great impact across many industrial sectors, such as manufacturing, transportation, energy, agriculture, healthcare, and public infrastructure. IIoT applications in each of these sectors are complex in their implementations and diverse in their usages and requirements. On the other hand, they share a set of well-recognized technical challenges that include safety, security and privacy, interoperability, reliability and resilience and these challenges need to be addressed in the context of Information Technology (IT) and Operational Technology (OT) convergence. Additionally, due to the large investment that is typically required to build IIoT systems, it is also a common challenge for many enterprises to determine how to get started and to drive the development of such systems so that they are capable of delivering the desired business value and the return on investment (RoI) when deployed.
To meet these common technological and business challenges effectively, it is obvious that an architectural foundation is needed. Without an understanding of how the system would look structurally, we cannot start to consider how to secure it. Similarly, without an idea of the interacting entities, we cannot enter any meaningfully discussion about their interoperability. Furthermore, it would be much more valuable if a common IIoT architecture is so constructed that it can be broadly applicable within and across industrial sectors. It enables the sharing know-how, and reusable technologies and system building blocks in a cross-sector ecosystem. A broad ecosystem that would spur more technology innovations, lower the costs, and speed up the implementation of IIoT systems.
The Industrial Internet Consortium (IIC) did just that in June 2015 when it published its first version of the Industrial Internet Reference Architecture (IIRA) . Since then, IIRA has been applied in the IIC’s testbed programs to serve as a common starting point for system design. It has also served as a common foundation for other technology deliverables within the IIC. From these activities and its applications in other IIoT system designs, useful feedback has been gathered.
During this period, IIoT technologies and applications have further evolved as well. To incorporate feedback, reflect new developments, represent the latest thinking of the IIC and the general IIoT community, and clarify some existing concepts and models, the IIC published an update to the IIRA, the Industrial Internet Reference Architecture version 1.8 (IIRA v1.8) . It is part of the IIC’s continuing effort to provide useful guidance, technological or otherwise, to the IIoT community to drive the growth of IIoT.

Figure 1 Architecture viewpoints and views

The basic structure of IIRA remains intact – it contains architectural concepts, vocabulary, structures, patterns and a methodology to address important common architectural concerns. It defines an architecture framework by adapting architectural concepts, constructs and approaches from the ISO/IEC/IEEE 42010-2011 Systems and software engineering — Architecture description standard. The IIRA v1.8 further clarifies how this framework is used to create the content of the reference architecture itself and how the reference architecture is to be applied to create concrete IIoT architectures.
The IIRA v1.8 maintains a business-value-driven concern-resolution-oriented methodology for driving the development of IIoT systems: Architectural concerns are identified and classified into the four viewpoints: business, usage, functional and implementation, wherein the concerns are analyzed systematically and resolved (see Figure 1). The results are documented in models and other representations in the respective view as the content of the architecture description. For clarity, The IIRA v1.8 adds a new description of viewpoints’ scope of applicability and relationship to the system lifecycle process.

Figure 2 Functional domains, crosscutting functions and system characteristics

The IIRA v1.8 retains the comprehensive system analysis in the functional domain (Figure 2) and further clarifies the concepts and relationship between the functional domains, crosscutting-functions and system characteristics. It also introduces the notion of trustworthiness of IIoT systems, which encompasses important system characteristics of safety, security, privacy, reliability and resilience – a concept well developed in the recently published Industrial Internet Security Framework (IISF) . It also examines how the IIRA functional domains map to a compute deployment continuum to reflect the latest thinking in IIoT architectures.
In the implementation viewpoint, the IIRA v1.8 continues the effort to provide useful and representative architecture patterns by adding a new layered databus architecture pattern in part derived from the IIC Smart Grid Testbed program.
The IIRA v1.8 also includes the considerations about design space offering a broad view of possible design parameters and their constraints in identifying, describing and resolving IIoT system concerns.
Finally, the IIRA v1.8 keeps what was Part 1 of the original version of IIRA and leaves the corresponding Part 2 to a separate volume (to be published shortly) as those sections are being replaced by the IISF, and other soon to be released stand-alone frameworks.
To sum it up, IIRA v1.8 generally represents incremental enhancements over its predecessor. It adds new descriptions and representations or otherwise clarifies on a few key ideas and relationships, highlighting their importance or making them clearer to understand. On the other hand, it  brings in some new and substantive ideas, e.g. on functional design across a compute deployment continuum, a new implementation pattern and design space considerations, all for raising awareness on important architecting concerns or providing additional representative solutions to address them.
The IIRA v1.8 continues to serve two main groups of readers: 1) IIoT system and component architects who design IIoT systems and system components, technologies and solutions within the vendors and implementers communities; 2) business decision-makers, plant managers, operations managers, IT managers and others who are interested in understanding how best to drive IIoT system development from business perspectives particularly in the context of IT and OT convergence.
With its release, the IIRA v1.8 advances in providing a common and consistent architecture template and methodology to the broad IIoT community:
• It makes it easier to discuss the specification of systems and compare options using common concepts and a shared vocabulary. It also facilitates an easy sharing experience and know-how in designing, implementing and operating IIoT systems across industrial sectors.
• It serves as a common foundation for identifying interoperability requirements and solutions within and cross systems, including systems of systems spanning industrial verticals to support the broadest interoperability.
• It provides a common architecture for vendors to create market-fitting system building blocks and technologies that are interoperable and applicable across industrial sectors addressing a broad market.
• It provides a common architecture for system implementers as a starting point for design and for choosing off-the-shelf commercial or open-source system building blocks and technologies.
• It helps drive towards an open, innovative and broad technology ecosystem across industrial sectors.
Altogether, IIRA v1.8 aims to enhance the ability of IIoT community to build safe, secure and reliable IIoT systems at reduced effort and risks, lower costs and shorter time to value.

About your Guest Blogger:
Dr. Shi-Wan Lin the CEO and a co-founder of Thingswise, LLC, a startup providing a streaming analytic platform as a turnkey solution that is purposely built for IIoT systems by adapting and innovating key IT technologies to meet OT requirements. Dr. Lin co-chairs various technical groups for the Industrial Internet Consortium (IIC), the Architecture Joint Task Group between Plattform Industrie 4.0 and the Industrial Internet Consortium and the National Institute for Standards & Technology (NIST) Cyber-Physical Systems Public Working Group. Dr. Lin is a leading contributor to the Industrial Internet Reference Architecture published by IIC. Previously, he worked for Intel for 10 years last as a Principal Engineer/Technologist in the Strategy and Technology Office in its Internet of Things Group and his other prior experience includes working for Sarvega, Inc (a Web Service/SOA/Security startup), Lucent Technologies and Motorola. Dr. Shi-Wan Lin has 20+ years’ experience in system architecture, Big Data, analytics, enterprise software, Cloud Service, system security and trust, telecommunications and wireless data communications in both large corporate and startup settings.