“OPC UA Reverse Connect” is a special connection mode in which the traditional roles of clients and servers during connection establishment are reversed – the server is responsible for initiating the connection to a client. This mode is intended for critical network environments (e.g. shop floor, production) where no inbound connections are allowed at all. basysKom has added support for “OPC UA Reverse Connect” to the open62541 stack. This article provides you with some entry points on how to use this new open62541 feature.
Using "Reverse Connect"
Reverse Connect is specified here: https://reference.opcfoundation.org/Core/Part2/v104/docs/6.14. Documentation on the open62541 server API can be found here: https://www.open62541.org/doc/master/server.html#id10. The client side is documented here: https://www.open62541.org/doc/master/client.html#connect-to-a-server. The open62541 code base also contains a ready to go example for a server implementing “Reverse Connect” here https://github.com/open62541/open62541/blob/master/examples/tutorial_server_reverseconnect.c.
OSADL
The Reverse Connect support was sponsored by the OSADL “PubSub over TSN Project – Phase #4”. It will become part of the upcoming 1.4 release of open62541, but is meanwhile already available from the master branch.
basysKom and OPC UA
basysKom is an official commercial support partner for the open62541 project and the maintainer of the Qt OPC UA module. basysKom is umati partner since May 2021. We have worked with customers from various industries to help with OPC UA efforts, offering technical consulting (system-/software-architecture, OPC UA modelling, feasibility studies and prototyping), training and coaching (OPC UA, open62541, Qt OPC UA) as well as development services focused on these areas. Please, get in contact to discuss how we can support you.
