Compliance Corner – March 2022

Interoperability (IOP) Event in March

We have scheduled our first IOP of this year. The IOP will start on March 21st 2022. It will be hosted by Honeywell in Phoenix Arizona. For those of you that can’t travel, the event will be a hybrid event, but you should be aware it will operate on Phoenix time (starting at 8:30am – 5:00pm MST). The IOP is open to all corporate members.

The following link can be used to find additional details and to register for the IOP event.

In addition to the normal Client/Server topics, these additional key topics will be included:

  • Global Discovery Service
  • Elliptical Curve Cryptography Security
  • PubSub

Many of these issues have been difficult to test remotely and have been waiting for an actual event.

CTT Release Schedule

The OPC UA specifications are rapidly expanding, which is putting strain on the certification environment. To help with this rapid growth we have been updating the infrastructure and tools related to certification. Some of these enhancements have already been released in the latest CTT, such as support for loading Companion Specification tests. Others will come out in the next few months, which will allow the CTT to expand the types of tests that can be automated and general support for enhanced OPC UA communication and security.

Starting this year, we have decoupled the release numbers used in the CTT. The CTT is composed of a binary application, test scripts, and test case definitions. There is also the version of the OPC UA specification that is being tested. Each item will have a unique version number. This will help vendors that track changes to the CTT for their automated build system. They will be able to quickly tell if test cases have changed, or if automated test cases have been updated. This will also allow us to release smaller patch releases, or enhancements to only the binary (which may be needed by other groups or are needed for beta work on scripts).

In the latest release, we included many new test case definitions and will continue to release many additional test case definitions in the next couple of releases. The test case definitions serve two purposes; they allow vendors to manually test compliance with a Profile/ConformanceUnit, and they help in verifying the specifications. The automation of these test cases will roll out at a slower rate. We are in the process of enhancing the new profile tool to automatically display the latest set of test case definitions. Remember all test cases are defined on ConformanceUnits which are grouped into Profiles. The new Profile tool, which can be accessed via, will make it easier to see the latest definitions of test cases.

If you do have questions on these topics or are interested in getting involved in our activities, please do not hesitate to contact us at

Paul & Alex