open62541 is free & open source

You can download it from GitHub. There is no SDK or run-time license fee.


If it’s free, why do I need a partner?

open Source  community project & Commercial support

Our open source product & associated support packages

Technology adoption framework

Our industry 4.0 technology adoption framework

Case study

Our industry 4.0 development & integration services



OPC UA SDKWe focus on helping customers right from the smallest of smallest sensors to customers who need an integrated TSN switch and embedded device profile.

Kalycito OPC UA Client Server SDK for embedded targets is based on open62541 – an open source implementation of OPC UA specification.

We have certifiable ports of open62541 available on different hardware and different operating system combinations. We also engage in quick prototyping and proof of concept projects. If you are interested in the embedded foot print numbers, performance numbers or certification of the solutions, you can book a meeting by clicking on the following link.

Software Stack Use Case Pub/Sub Client/Server Security Processor &
Nano Embedded Profile + Pub/Sub Small sensors and actuators Small microcontrollers with external SRAM
Micro embedded UA server profile + Pub/Sub Gateway Devices, end nodes ARM Cortex M4
Micro embedded device server profile + Pub/Sub + Security PLCs, Controllers, Edge devices, end nodes ARM Cortex A9
Micro embedded device server profile + Pub/Sub + Security + TSN PLCs, Controllers, End-point-gateways, Edge devices, end nodes ARM Cortex A9
Embedded device server profile + Pub/Sub + Security + TSN PLCs, Controllers , End-point-gateways, Edge devices, end nodes ARM Cortex A9

Commercial support for open62541

OPCUAWe provide commercial support for customers using open source OPC UA stack – open62541. We help you learn OPC UA technology and integrate into your products – including porting open62541 stack to your embedded architecture and certifying the product for compliance from OPC foundation. We also provide annual maintenance packages and priority support for critical bug-fixes.

open62541 is a free and open source software maintained by a community of developers and users. The certified release v1.0 was prepared by Fraunhofer IOSB and Kalycito Infotech with funding from an industry consortium via the Open Source Automation Development Lab (OSADL) eG. More details of this project can be found here.

The certified feature set of open62541 v1.0 is in conformance with the ‘Micro Embedded Device Server’ Profile of OPC Foundation supporting OPC UA client/server communication, subscriptions, method calls and security (encryption) with the security policies ‘Basic128Rsa15’, ‘Basic256′ and Basic256Sha256’ and the facets ‘method server’ and ‘node management’. open62541 also implements OPC UA publisher/subscriber communication.


OPC UA & Time Sensitive Networking

Today, the biggest challenge companies face when exploring new business opportunities is interoperability and solving this challenge will unlock the potential of Industry 4.0. We are thought leaders in this space. The new initiative by the OPC Foundation – OPC UA FLC promises vendor independent and end-to-end connectivity from sensor to cloud. We build on top of this major global initiative.

We are pioneers in building the open source eco-system for OPC UA including TSN. We started early and released PubSub in open source immediately after OPC Foundation released the part 14 specification. Even companies who hold proprietary IP in one part of what we do, leverage our work on other parts of the ecosystem to address their customer use cases. Our goal is to be a single eco-system for all the work involved in the Industry 4.0 end point device and edge device platforms, that includes optimizing the OS for real-time performance, time synchronization, functional and configuration parts of OPC UA, TSN and security. The following architecture diagram shows the different components that are part of an Industry 4.0 edge/end-point device.

OPC UA Architecture

Engaging with us is easy

Join & fund community project

  • Get voting rights
  • Influence OSS roadmap
  • Reduced R&D costs

Buy support & annual maintenance packages

  • Priority bug-fixes
  • On-demand support
  • Certifiable updates

Avail consulting & integration services

  • Training & Consulting
  • Software Integration
  • Continuous Integration

New to Industry 4.0 & OPC UA?

Watch our video introduction to Industry 4.0, OPC UA & Time Sensitive Networking.


open62541 stack is available open source and more information on the features shall be viewed in Github

Click here for officially certified stack release in English, German and French

Quick Start Guide


How to run OPC UA stack open62541 with realtime PubSub on realtime Linux and TSN using Intel i210 Ethernet card


Download our latest whitepaper


This whitepaper based on use-cases described in the ‘IEC/IEEE 60802 TSN Profile for Industrial Automation’ provides a series of measurements done in the Embedded Optimized OPC UA stack along with TSN drivers and a real-time Linux system and shows that the open source solution is able to achieve cutting edge performance demanded by modern Industry 4.0 devices.