What is OPC and OPC UA?

OPC and OPC UA (Unified Architecture) are industry standards that enable software to connect devices, machines and systems from different manufacturers using same interface. OPC servers add value for any device, machine or system, as it reduces any integration or application software development costs. Similarly OPC clients and application software utilizing OPC client features, can be connected to any OPC server in a standard way without customization.

OPC Foundation is dedicated to ensuring interoperability in automation by creating and maintaining open specifications that standardize the communication of acquired process data, alarm and event records, historical data, and batch data to multi-vendor enterprise systems and between production devices. Production devices include sensors, instruments, PLCs, RTUs, DCSs, HMIs, historians, trending subsystems, alarm subsystems as used for example in process industry, manufacturing, building automation, traffic management, energy production and smart grids.

All OPC specifications are developed and managed by OPC Foundation. The vision of OPC is to be the foundation for interoperability for moving information vertically from the factory floor through the enterprise of multi-vendor systems as well as providing interoperability between devices on different industrial networks from different vendors.


The standard communications and systems integration protocol for automation, Industrial Internet, Industry 4.0 and Internet of Things

OPC UA (Unified Architecture) is the new generation of OPC

  • Replaces DCOM communication with binary TCP/IP, HTTPS and SOAP (Web Services)
  • Enables OPC in any operating system and language
  • Enables OPC in devices (embedded software)
  • Enables WAN (Secure Internet/Intranet/Extranet) connections
  • Improves Security Management
  • Combines all previous protocols to a common data model
  • Was accepted as IEC standard 62541 in 2011

OPC UA Stack

OPC UA application development is based on a layered architecture. The OPC UA Stack implements the TCP/IP communication protocol defined by the OPC Foundation. There are different stacks for different development languages and environments, including AnsiC Stack, .NET Stack and Java Stack. Prosys is a major contributor to the Java Stack.

The different OPC Foundation stacks are interoperability tested, so you can use your application with other OPC UA applications, independent of the development environment in which they are created.

The OPC UA Stack is provided by the OPC Foundation and it is available to the Corporation members of the OPC Foundation. The stack is also included in the SDK distributions. The license from OPC Foundation enables you to distribute it also with your own applications.


Although the stack makes all OPC UA service calls available, another layer is required on top of it. The services of the OPC UA servers are expected to function in a certain way, and the client applications must also implement certain infrastructure to enable full use of the protocol. These are typically available in OPC UA SDK products.

The following picture depicts the functionalities of the stack and the SDK. In principle, the stack handles the communication protocol, whereas the SDK implements the base services. The services are more important on the server side, but there is certain infrastucture that needs to be taken care of on the client side as well.

What can you do with OPC UA?

End users

Whether you are working in process industry, manufacturing, machine control, power generation, smart grids or, for example, traffic management, you can integrate all your production site devices, automation systems and software applications such as Asset Management, MES and ERP, using one secure and platform independent standard. With OPC UA you can also build distributed Internet and cloud based systems connecting your remote devices and I/O to a core server and database, allowing OEE, device diagnostics, reporting and other applications.

Device and machine vendors

You can make your products inter-operable with products of other vendors, thus enabling your customers to build total systems and you getting the orders. Using a standardized and secure technology makes the integration more reliable and cuts your costs as you only need to make it once. Industrial Internet and Internet of things (IoT) are a strong trend, and OPC UA offers you a good communication protocol when you develop your own products and systems fitting into that framework.

System integrators

When you integrate systems of multiple vendors to provide total solutions to your customers, you want to use standardized, reliable, secure, scalable and platform independent technology. This is what OPC UA offers to you. Furthermore, its continious development is ensured by over 400 international members of OPC Foundation. When you select OPC UA as your core communications technology, you can use your software and professional knowledge over and over again, executing your projects economically and on schedule.

Software companies

One of the key features of successful enterprise software is how interfaces to other systems are implemented. For HMI, SCADA, MES and ERP, monitoring, quality control and reporting, and for numerous other software applications, OPC UA offers a new way to solve the integration challenge in a productive way. When you develop your own software you want to maximize the number of possible customers while ensuring high quality, and both are achieved by offering OPC UA as a standard interface.

About Prosys

Prosys is a leading provider of professional OPC software and services with over 10 years of experience in the field. OPC and OPC UA (Unified Architecture) are communications standards used especially by industrial and high-tech companies.

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Symboticware chose Prosys because of their excellent reputation for customer support and their ability to function within a Linux based operating system. The Prosys OPC UA Java SDK has been very reliable and has performed very well in our system benchmark testing.

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