open62541 Server SDK

open62541 Server SDK

Member: Kalycito Infotech Private Limited

Product website:

open62541 is an open source implementation of OPC UA written in the common subset of the C99 and C++98 languages and can be found in GitHub at -

The library is usable with all major compilers and provides the necessary tools to implement dedicated OPC UA servers or to integrate OPC UA-based communication into existing applications.

The sample server (server_ctt) built using 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). 

As SDKs cannot be certified directly, the certification process has been made using the sample server application that comes with the open62541 SDK and has been created using the SDK..

PubSub (UADP) is implemented in open62541. But the feature cannot be certified at this point in time (Sep-2019) due to the lack of official test cases and testing tools.

open62541 is licensed under the Mozilla Public License v2.0. So the open62541 SDK can be used in commercial projects that are not open source. Only changes to the open62541 SDK itself need to be licensed under the same license when copied and distributed.

open62541 is maintained by a community of developers and users. The sample server that was certified was prepared by Fraunhofer IOSB and Kalycito Infotech with funding from an industry consortium via the Open Source Automation Development Lab (OSADL) eG. OSADL continues to actively support the project and fosters addition of new features and functions. To do so it welcomes new participants who may select from various contribution levels as outlined at

Fraunhofer IOSB is responsible for the overall architecture of open62541 and maintains the project jointly with a cross-organizational team from research and industry -

Kalycito Infotech provides commercial support for customers interested in integrating open62541 into their products and getting them certified. Kalycito specializes in IT/OT integration and provides consulting and software integration services in embedded, real-time networking and cloud areas -

Micro Embedded Device Server

Method Server
Node Management Server

SecurityPolicy - Basic128Rsa15
SecurityPolicy - Basic256
SecurityPolicy - Basic256Sha256

User Token - Anonymous Facet
User Token - User Name Password Server Facet

Micro Embedded Device Server





Open62541 OPC UA Server (server_ctt)