TechnologyFebruary 1, 2024

OPC UA interoperability for cloud solutions

Industrial security is a priority for users

The goal of the OPC UA Cloud initiative is to recommend, harmonize, and steer the activities of individual technical working groups and create best practices, an overall reference architecture, as well as open-source reference implementations, combining the output of the individual working groups.

Digitalization in manufacturing is resulting in a world divided between those who possess and effectively utilize data and those who lack access to those resources.

This is a barrier to both corporate success and macro-economic growth. Legislators (such as the EU with the upcoming Data Act) are responding to this by requiring vendors to share data among much broader eco-systems. In parallel to require broader eco-systems, central use-cases for traceability like the Digital Product Passport (DPP) and security aspects like in the Cyber Resilience Act (CRA) are defined.

At the OPC Foundation, we believe that this will create a greater need for interoperability of end-to-end information models and data communication to support these legislative demands.

We will replicate the best-practice collected in the OPC Foundation Field Level Communications Initiative bringing in experts in applications to complement the technology experts from the OPC Foundation. By initiating an OPC Foundation Cloud Initiative, to bring greater focus of existing working groups on actionable user challenges and opportunities for enhancement and initiating new working groups to develop OPC UA technology into new cloud-centric applications.

Today, OPC UA has established itself as the industrial interoperability standard in on-premises, OT environments, field-level communication (OPC UA FX), as well as industrial Edge applications. Therefore, it is not surprising that OPC UA users also want to leverage their existing investment in OPC UA Information Models and communication patterns in IT and cloud applications by creating secure, interoperable, cloud architectures. These architectures must focus on open solutions for data analytics, digital twins, industrial metaverse, and artificial intelligence; but also avoid vendor lock-in. They must further define edge-to-cloud and cloud-to-cloud communication patterns and a means to securely store OPC UA Information Models in the cloud.

Thankfully, the OPC Foundation established several working groups in this area in prior years and can now combine them under a single OPC UA Cloud initiative. This will also help bring clarity to seemingly overlapping national and international standards and other initiatives in this area.

OPC UA cloud interoperability

List of OPC Foundation working groups with focus on OPC UA Cloud Interoperability:

  1. UA Cloud Library – A query-able online store of OPC UA Information Models.
  2. OPC UA over MQTT Working Group – secure transport from edge to cloud and cloud to cloud.
  3. OPC UA over MQTT Prototyping Group.
  4. OPC UA over MQTT Testbed.
  5. OPC UA REST Interface – cloud-based OPC UA server access.
  6. OPC UA WoT Connectivity – standardized industrial connectivity software configuration.
  7. OPC UA Industrial Metaverse Working Group.
  8. OPC UA AI leveraging Large Language Models Working Group (currently getting established).
  9. OPC UA Data Spaces Working Group (currently getting established).

Open source solutions

Here is a list of open-source reference solutions with an overall focus on OPC UA Cloud Interoperability:

  1. UA Cloud Library: Cloud-neutral reference implementation.
  2. UA Cloud Publisher: An OPC UA PubSub telemetry publisher.
  3. UA Cloud Commander: An online command & control app for OPC UA servers.
  4. UA Cloud Action: A cloud-based app to trigger an action for UA Cloud Commander.
  5. UA Cloud Dashboard: An online dashboard for OPC UA PubSub data.
  6. UA Cloud Twin: Digital Twin adapter for OPC UA PubSub data from the Digital Twin Consortium.
  7. UA Cloud Viewer: An online viewer for OPC UA Information Models.
  8. AAS Repository: An Asset Admin Shell Repository with OPC UA modelling support.
  9. UA Edge Translator: a reference implementation for industrial connectivity software.
  10. IIoT Starter Kit: A set of quick-start samples for OPC UA over MQTT.

The goal of the Steering Committee of the OPC UA Cloud initiative is responsible to recommend, harmonize, and steer the activities of the individual technical working groups and create best practices, an overall reference architecture, as well as open-source reference implementations, combining the output of the individual working groups.

This will not only lead to greater interoperability between different cloud solutions and enable the use of OPC UA Information Models for semantically-rich data analytics in the cloud, but also lead to cost reductions of these solutions.

Find more information on the OPC Foundation website:

Building the Digital Product Passport

The Digital Product Passport is coming. And sooner than you think!
Soon, the European Commission will be voting on the specification of the Digital Product Passport (DPP). While the specification is written in a technology-neutral fashion, it is clear that very soon, the first implementations based on concrete technology need to appear. Realistically, to meet the Commission’s goal of introducing the DPP by 2027, these implementations need to be started now.

One Candidate: The Asset Administration Shell
The Asset Administration Shell (AAS) has been developed by the German Plattform Industrie 4.0 over the last 10 years. It now has a file exchange format, a technology-neutral meta model and a REST interface specified and all three are currently being standardized through the IEC. The AAS is evaluated as a standardized data exchange framework for the manufacturing supply by consortia in Germany and beyond. There are also several data model templates released by the Industrial Digital Twin Association (IDTA), the new owner of the AAS specification. However, what the AAS still lacks today are commercial tools to develop and build Asset Admin Shells and broad industry adoption.

OPC UA: the Industrial Interoperability Standard
At this point it is important to bring OPC UA into the equation: OPC UA has vast industry adoption and is an IEC standard since 2010. Most manufacturers have adopted OPC UA and some even made it a requirement in purchasing agreements. There is a very large ecosystem of commercial OPC UA modelling tools available and there are over 153 standardized data models available free of charge via the OPC Foundation. Incidentally, the OPC Foundation is close to reaching the 1000-member mark and it is still seeing exponential growth in its member ecosystem. Millions of products use OPC UA today.

Combining Ecosystem to Accelerate DPP Adoption
It doesn’t take a rocket scientist (although OPC UA is also used in rockets!) to figure out how both the AAS and the OPC UA technologies can fulfill and accelerate the adoption of the DPP. What the AAS is still lacking today, OPC UA can cover, and many believe that a combination of the two ecosystems of AAS and OPC UA is the winning formula. In such a scenario, both technologies can play to their strengths: The AAS covers the data exchange for the DPP along a manufacturing supply chain while OPC UA covers the DPP modelling requirements.

Seeing is Believing
Most folks only believe something can work when they see it in action. Therefore, together with their partners Clean Energy and Smart Manufacturing Innovation Institute (CESMII) and the Digital Twin Consortium (DTC), the OPC Foundation built a demonstrator showcasing the combination of AAS and OPC UA technology at last year’s Smart Production Solutions (SPS) trade show in Germany. Incidentally, this demonstrator was built in just 3 days! It uses OPC UA to model the DPP while using the AAS file exchange format as well as the AAS REST interface to distribute the DPP. With this combination, the successful rollout of the DPP can be easily achieved.

Stefan Hoppe, President & Executive Director, OPC Foundation