OPC UA – Open Platform Communications Unified Architecture

Smart. Semantic. OPC UA – structured data up to the cloud.

When it comes to networking and standardization or cybersecurity – the requirements for industrial networks are increasing. Here, the Ethernet-based OPC UA (Open Platform Communications Unified Architecture) communication standard offers the best conditions for digitalization, independent of platform and manufacturer and with integrated security mechanisms. That’s why Siemens relies on OPC UA for vertical connectivity to the cloud as well as for communication between machines (M2M). For real-time communication at the field level, Siemens combines OPC UA with PROFINET – and does so in a common Industrial Ethernet network.

Do you want to learn more about OPC UA?

Contact us

The OPC UA standard

A milestone for automation in the digital environment

To handle the requirements of tomorrow’s industry, industrial networks will need to be able to meet ever-increasing demands. Companies will need convergent, end-to-end, secured networks that are flexibly scalable, dynamically adaptable, and able to accommodate large numbers of users – naturally, with the fastest possible response times. OPC UA is an important component.

OPC UA speeds up the digitalization of your company

The open, platform-neutral communication standard OPC UA enables seamless communication with third-party applications and can be flexibly scaled to meet specific requirements. With its semantic capabilities, OPC UA supports more than just data transmission: It also contains a unique information model. Proven security mechanisms like authentication, authorization, and encryption guarantee a secure connection. In addition, PROFIsafe mechanisms are being prepared for OPC UA to permit standardized, safety-related communication between machines. OPC UA can also be integrated into existing Industrial Ethernet networks and can run on the existing PROFINET infrastructure without compromising performance.

That’s why Siemens relies on OPC UA as the number-one open interface from the control level to higher-level SCADA, MES, and ERP systems all the way to the cloud.

Fair, Nov 8 - Nov 10

SPS 2022

Make it real! Become a Digital Enterprise. We'll show you how at SPS 2022 from November 8th - 10th!

Technology innovations, best-in-class automation solutions, impressive exhibits and great networking opportunities are waiting for you! Meet us there and learn how to accelerate your digital transformation.

Communication mechanisms for different requirements

Line integration with OPC UA

OPC UA and its companion specifications enable fast and cost-effective line integration with high scalability, fault-free commissioning, and a fast factory acceptance test. Thanks to the internationally defined OPC UA companion specifications, you benefit from the line integration of standardized data interfaces and status models – allowing you, for example, to easily adapt machine interfaces and reuse modules for different plants.

OPC UA client/server

OPC UA with client/server communication is used extensively in automation. With this proven, one-to-one communication mechanism, each OPC UA client obtains access to the data on the OPC UA server via point-to-point communication. The OPC UA client sends a request to the OPC UA server, from which it receives a response. This form of communication enables a reliable, secure, encrypted data exchange with reduced bandwidth and no loss of data, even if the environment and network quality are sub-optimal and are experiencing disturbances. Client/server communication is always based on TCP/IP.


In the OPC UA with PubSub (publish/subscribe) model, a one-to-many or many-to-one communication mechanism is used: A publisher makes data available that can be received by any number of subscribers in the network. OPC UA PubSub communication can be transmitted via UDP or directly on layer 2. Depending on the technology used, this can result in short cycle times. In conjunction with Time-Sensitive Networking (TSN), OPC UA PubSub therefore enables real-time communication at the control level and meets the demands of time-critical applications.

Time-Sensitive Networking – another step into the digital future and towards IIoT (Industrial Internet of Things)

Guaranteed, scalable bandwidths, optimized Quality of Service (QoS) mechanisms, real-time capability, and very low transmission latency in communication networks: Siemens relies on Time-Sensitive Networking (TSN) to get the most out of automation networks while meeting constantly growing requirements. As a result, communication from machine to machine and from machine all the way up to the operator level can achieve new heights in terms of speed and reliability. TSN is defined within the framework of IEEE 802.1 and combines a series of individual standards that affect only the data-link communication layer (layer 2).

Good reasons to use OPC UA

Learn more about OPC UA:

Open Brochure

OPC UA portfolio

Siemens products and systems with OPC UA interface + supporting tools

Siemens offers a comprehensive hardware and software portfolio for Totally Integrated Automation (TIA) that extends from the field level to the control and operater levels. As an open communication standard, OPC UA plays an important role for the entire TIA portfolio.
Knowledge pool

One step ahead with the OPC UA webinars

Visit our webinar series on all aspects of OPC UA, where our experienced experts provide simple and clear explanations of important topics relating to the Ethernet-based communications standard.

Advanced knowledge through OPC UA webinars – learn from the experts:

Development with outstanding prospects

Open Platform Communications – Unified Architecture (OPC UA) was developed by the OPC Foundation, which was created in 1996 with Siemens as a founding member. The OPC Foundation is an international nonprofit organization with over 450 members from all sectors of industry. It works closely with users and vendors to develop the open, vendor-independent standard – and it does so successfully, according to this statement by Holger Junker of the German Federal Office for Information Security (BSI): “The only communication technology in the factory with implicit security features and the potential to meet the challenges posed by Industrie 4.0 that I am aware of today is OPC UA.”

Downloads, support, service

Even more OPC UA for you

Take advantage of additional sources of information to learn more about OPC UA, the open communication standard for the digital future and Industrie 4.0. Brochures, informational materials, technical data, FAQs, and services – you’ll find them all here!

Support Services

In case of an emergency, Digital Enterprise Services offer you a wide range of services - by phone and online, anytime and anywhere with online support, technical support, the Siemens Industry Service Card and Managed System Services.

Spare Parts Services

he Spare Parts Services from Digital Enterprise Services are available worldwide and ensure a smooth and fast delivery of spare parts - and thus optimal system availability. 

Training Services

Industrial learning for every need with training services, continuously and sustainably. Our experts from SITRAIN and Vizendo Virtual Training Solutions offer the right training for you - classroom trainings, online or virtually. 

Teaser Cybersecurity for Industry
Cybersecurity for Industry

Security information

In order to protect plants, systems, machines and networks against cyber threats, it is necessary to implement – and continuously maintain – a holistic, state-of-the-art industrial security concept. Siemens’ products and solutions only form one element of such a concept. For more information about industrial security, please visit.




Our experts are ready to help

Do you want to know more about OPC UA and the Siemens strategy? Would you like more specific information on how OPC UA and PROFINET will interact in the future? Our experts are happy to help.

We’re happy to answer all your questions about OPC UA:

Contact us