OPAF Services

Ensure interoperability and compliance with Open Process Automation TM Forum (OPAF)OPAF standard.


Embracing new technologies in this digital reform is the need of the hour for next generation process and factory control automation. As a result, companies are anticipating a data deluge from intelligent sensors, actuators and robots among other industrial equipment. They are gearing up for exponential adoption of computing power, 5G, AI, ML, Big data analytics, 3D technology, new HMIs with touchscreens, AR/VR capabilities among others to help them in their digital transformation journey.

However, the current scenario in the process control automation industry in the lower layers like L0, L1 and L2 layer is a closed, highly proprietary and distributed setup with several OEMs, multiple vendors, systems integrators and business stakeholders being directly involved.

They are challenged by end-user demand for standardization in the OT layer, enabling interoperability among process automation technologies, along with providing a holistic view. The business need to reduce capital and lifecycle costs for process control; making scalability and cybersecurity an integral part of these systems is another compelling factor.

The Open Process AutomationTMStandard (O-PASTMStandard) or “Standard of Standards”popularly known addresses this immense pressure to provide an open, interoperable, and secure-by-design process automation systems architecture. This standard ensures interoperability among existing control systems at every level, providing certified systems and components that conform to agreed upon set of standards. This will also address both business and technical challenges in process automation seen in many different vertical industries.

Here’s a quick uptake on the O-PASTM Standard and how it’s going to play a major role in the future of the process automation industry.

Open Process AutomationTM Standard
(O-PASTM Standard) Evolution

The “Standard of Standards” is an initiative started in 2016 by The Open Group Open Process AutomationTMForum (OPAF). This global consortium of end-users, system integrators, suppliers, and other industry standards organizations work together to ensure that future automation systems meet true multi-vendor interoperability, adaptive intrinsic security and an easy pathway for systems migration.

The new architecture brings more standardization and flexibility in the existing process automation systems that uses Distributed Control Systems (DCS) and Programmable Logic Controllers (PLCs). As automation applications require ultra-high availability and real-time performance, process automation systems have always been highly proprietary.

So, here’s why we need the totally new standard that adds value for end users, integrators and seller in this new-age IT and OT integration.

  • Easy integration of various components used in setup
  • Enables innovative value creation
  • Automation of provisioning, initiation, and life-cycle management of legacy as well as OPAF compliant devices
  • Overall reduced cost of control system upgrades or replacements
  • Discover new business markets and customers
  • Stay relevant to existing customers with new products and services
  • Empowers workforce with a safe and secure design

Before we deep dive into the intricacies of the O-PASTM Standard, there are three versions of the standard that the OPAF has created or is in the pipeline.

  • Version 1, first published in 2019, addresses the key quality attribute of interoperability.
  • Version 2, published in January 2020, addresses configuration portability.
  • Version 3, coming in 2022 will address application portability and orchestration.

Under the hood of O-PASTM  Standard

The “Standard of Standards” is a collaborative effort of various industry groups such as OPC Foundation, Control System Integrators Association (CSIA), Distributed Management Task Force (DMTF), specifically for the Redfish API, FieldComm Group, Industrial Internet Consortium (IIC), International Society of Automation (ISA) and NAMUR among others.

This collaboration is visible as the current 2.1 version which has significant contribution from the OPC Foundation (for OPC UA connectivity), ANSI/ISA 62443 for security and DMTF Redfish for systems management.

The latest version 2.1 Preliminary Standard consists of the following parts:

  • O-PAS Part 1 – Technical Architecture Overview (Informative)
  • O-PAS Part 2 – Security
  • O-PAS Part 3 – Profiles (Informative) (available separately as S211)
  • O-PAS Part 4 – O-PAS Connectivity Framework (OCF)
  • O-PAS Part 5 – System Management
  • O-PAS Part 6.1 – Information and Exchange Models: Overview and Interfaces
  • O-PAS Part 6.2 – Information and Exchange Models: Basic Configuration
  • O-PAS Part 6.3 – Information and Exchange Models: Alarm and Events Configuration
  • O-PAS Part 6.4 – Information and Exchange Models: Function Blocks
  • O-PAS Part 6.5 – Information and Exchange Models: IEC 61499 (Upcoming)
  • O-PAS Part 6.6 – Information and Exchange Models: IEC 61131
  • O-PAS Part 7 – Distributed Control Platform

Why O-PASTM Standard is a Future Requirement for Industries?

In the automation industry, the lower L1, L2 layer is heavily proprietary with a tight vendor control over the devices where the PLC’s, DCS, sensors, actuators and IO devices operate. Here the industrial process data is continuously collected, transformed, transmitted and ingested across the network/communication layers for it to make sense by the various stakeholders like operators, system integrators and business leaders.

In the current setup, with OPC UA we are able to obtain unified and consistent data from any layer (from L1, L2, to L4, L5 layer). With this standard, the intent is any component in the OPAF architecture should talk to any component across the network/communication layers.

With OPC UA providing standardization in the higher layers, the automation industry faced additional pressure to provide standardization even in the lower network levels. The question now is how to leverage the O-PASTMStandard and its various open process automation (OPA) technologies in next generation process control systems. This is possible with an OPA-based control system designed to support integration of best-in-class components and provide both configuration and application portability across components from different suppliers. This standardization will not only affect the hardware but also the software inside these components.

For a more detailed view on the role of OPC UA in OPAF Standard, check out our blog here:https://utthunga.com/blogs/role-of-opc-ua-in-opaf-open-process-automationtm-forum-standard/

OPAF Architecture

In a nutshell, the OPAF architecture allows secure data exchange and flow from DCNs and/or legacy non-complaint DCS, PLCs and IO devices over a common OCF bus. This bus is based on the OPC UA communication standard that allows the gateway DCNs to provide the raw process data to the advanced computing platform (ACP) for further data processing. All this data orchestration and system management is handled by the OSM that is basically the brains behind the entire OPAF architecture.

The architecture of the O-PASTMStandard is as shown below. This shows the different components that form the building blocks of this standard.

Figure: DCNs in an Open Process Automation System
Based on the image from ARC web- https://www.arcweb.com/industry-best-practices/what-distributed-control-node

A brief understanding on the various terminologies mentioned above is necessary to grasp the overall architecture of the OPAF standard.

Distributed Control Node (DCN)

It is evident from the above figure that DCN is the heart of this architecture. This essential component is OPAF complaint and is the module that brings standardization to the OT layer. They are basically field edge devices connected to the field wiring.

DCNs are capable of control, running applications, and other functions for seamless data exchange with the higher layers. This small, low-cost IO and process control component combines the capabilities of today’s DCS, I/O modules and controllers. In an open process automation system there may be just a few or up to several thousand DCN modules. The runtime software can be configured to selectively provide control application level communication and function block execution services.

O-PASTM Connectivity Framework (OCF bus)

The real-time bus is present across the OPAF Testbed and supports the transport of data to all components in the system. OPC UA based communications and data models that are standardized for OPAF are used for communicating over OCF. This connectivity framework with message bus architecture allows different DCNs to communicate with each other. Even the legacy or non-OPAF compliant devices can be integrated into the new OPAF architecture.

Advanced Computing Platform (ACP)

ACP is a computing platform with different applications running on a hardware agnostic platform for better maintenance, energy monitoring, management and optimization prescriptions. It performs data processing with different functional requirements and presents it to the OCF Bus as per the standard interfaces. Some of the functional requirements that are handled by ACP are data acquisition, filtering, data and event historization, data presentation, audit trails, diagnostics monitoring and prescriptions. The gateway DCN is used to host simple applications to have a base ACP.

O-PASTM Communication Interface (OCI)

Device vendors are allowing end-users to add, configure and program the software components of the hardware devices based on their requirements. In order to make the device visible as a DCN to the rest of the system, the software layer OCI can be added as an embedded application on to any such non-compliant flexible architecture-based device.

Orchestration and System Management (OSM)

Orchestration and System Management is a centralized system that deploys, configures and manages the entire OPAF architecture. Most of the vendor specific tools, orchestration masters, system management clients etc., are used to develop and build OSM. Different scripts and other custom tools are that are developed to meet the OSM requirements are deployed and executed from here.

Gateway DCN

Existing PLC and DCS controller devices that are not compliant with OPAF standards are integrated to the new system architecture through a Gateway DCN. These gateways facilitate easy configuration and data exchange from various endpoints like IO, PLCs, DCS, etc. Their multiplatform, scalable and portability features enable easy configuration of the end points for data point mapping, data source, alarms, events and HDA of the aggregated data over OPC.

Why Utthunga for O-PASTM Standard Implementation

Industries are quickly realizing the business and technical value O-PASTM Standard brings to the table. OPAF specification is evolving at fast pace and currently only a few components have been specified in great detail by OPAF Forum. With such limited insights, we at Utthunga serve as global advisors and technology partner for the OPAF community.

Our exclusive focus will mainly be on:

  • Contribution to OPAF specification to make positive impact in the industrial automation space
  • Serve as trusted partner for OPAF adoption for industries and suppliers
  • Collaborate with end users for OPAF Test bed & DCN implementation in production environment
  • OPAF compliant suppliers for connectivity and simulation for specific industry needs

Utthunga is a Silver member of The Open Group and our close association with various industry consortiums such as OPC Foundation, ISA and FieldComm among others, provides us direct access to technologies and strategies available for the enhancement of the O-PASTM Standard. Our OPAF consultation services is an initiative to ensure your platform achieve operational excellence and cost optimization as well as to validate the components for compliance with the OPAF standard.

Our OPAF Services

We offer both DCN and Testbed development services in order to ensure that, future and existing components used in the industrial process automation setup are interoperable and comply with OPAF standard.

Our approach begins with understanding the end users’ requirements (system as well as validation) and present a roadmap which defines the scope, standards, areas, schedule, milestones, risks and deliverables of your project.

A typical DCN or testbed development involves implementing the technical feasibility of an open process automation architecture and to create a system with components from multiple suppliers. All the while confirming to standards wherever possible, including OPC-UA for connectivity, IEC 61131-3 for control functions and IEC 61499- 4 for execution.

Our Capabilities:

  • System integration expertise in process control, automation, system design, programming, cloud, 3rd party integration, etc. for various disparate systems spread across remote locations.
  • OPC UA expertise in OPC connectivity via uOPC Suite, our proprietary connectivity framework. Our 14+ years of hands-on OPC technical, functional, operational and domain expertise helps to develop OPC UA based products and solutions across different industry verticals. With our understanding of the OPC UA Companion Specifications & OPC Information Models, our solutions ensures seamless horizontal and vertical interconnectivity between systems. Our knowledgeable OPC engineers are experts in developing embedded OPC UA applications with client/server and PubSub communication model along with TSN capabilities.
  • Security expertise ensures secure data exchange to validate cybersecurity capabilities as per Part 2-OPAF specification, IEC 62443 security levels as well as perform OPC UA security conformance validation. Our services include security assessment, engineering and validation across applications and systems. The team is well versed in the general security standards (OSWAP, CERT, AWS/Azure, PTE, PCI DSS, etc.) and ICS, IIOT & OT-IT standards (ISA/IEC 62443, ISO27000 series etc.)
  • V&V expertise in generic & customizable platforms for hardware and firmware design verification. Our skilled engineers test various vendor products that can be qualified as DCN as per OPAF. We also test various components of the testbed including the Gateway DCNs, devices (IO, PLCs, DCS etc.), communication bus & interface through process/device simulations.
  • Virtualization expertise in network, storage, communication as well as data
  • Protocols expertise in standard industry & proprietary protocols, V&V of protocols implementation
  • Supporting OPAF technologies and standards:
    • Cloud: AWS, Azure, PubSub over MQTT and AMQP
    • IIoT: Storage, Machine Learning, Analytics, Digital Twin etc.
    • Virtualization: Docker containers, orchestration, Dockerization Hypervisor, separation micro kernels
    • Automation: Automation ML, PLCOpen Programming
    • OPC: OPC Classic, UA, PubSub, Profiles, OPC Security, Information Modelling Client/Server, PubSub application development


The Open Group’s focused approach to provide an open, secure by design and interoperable industrial control systems through the O-PASTM Standard is opening doors for a federated process automation ecosystem. Utthunga leads from the front as a technical guide and partner for your OPAF implementation. Businesses can combine the existing OPA development work and technological expertise of The Open Group with our proven understanding of your technical requirements to create an OPA system. Prepare your business for an OPAF ready industrial process automation ecosystem with O-PASTM Standard and Utthunga’s expertise.

If you would like to take your business to the NEXT LEVEL, we are here to assist you!