Compliance and conformance

What you will be able to do

• You can explain profiles, facets and conformance units and how they nest.
• You can read a server's ServerProfileArray and predict what it will refuse to do.
• You can find the conformance units behind any standard node.
• You can read a Compliance Test Tool report.
• You can describe the product certification process accurately, including what it is not.

Syllabus

1. 1
   See how profiles, facets and conformance units nest

   Three levels of granularity, defined in Part 7. The vocabulary that makes every vendor datasheet readable.

   Asset A real profile decomposed into its facets and their conformance units

   8 min
2. 2
   Read ServerProfileArray

   What a server claims, in its own words, in a node you can read in ten seconds.

   Asset ServerProfileArray from four servers, decoded, with what each claim implies

   8 min
3. 3
   Spot an over-claimed facet

   The Compliance Test Tool exercises every claimed facet, so over-claiming is a top cause of failed certification, and even the OPC Foundation's own reference server advertises fewer facets than it implements.

   Asset A server claiming a facet it does not implement, with the failing call that proves it

   8 min
4. 4
   Use the capability codes

   The ServerCapabilities short codes as a fast complement to the profile array.

   Asset The full capability code list with what each maps to, and four real servers' codes

   7 min
5. 5
   Find the conformance units behind a node

   Every released nodeset ships a documentation CSV mapping each standard NodeId to its spec section and its conformance units. Almost nobody uses it, and it is the cleanest way to learn this.

   Asset A conformance-unit lookup for six standard nodes, taken from the released nodeset CSV

   9 min
6. 6
   Learn what the CTT does

   Script-driven testing per conformance unit, pass, fail and warn, and how both major open stacks gate their releases on it.

   Asset A CTT run structure with the conformance units exercised, and a sample result set

   8 min
7. 7
   Read a CTT report

   Telling a real failure from a configuration mistake from an over-claimed facet.

   Asset A CTT report with three failures, each traced to its actual cause

   8 min
8. 8
   Understand product certification

   Independent test labs, per-product and per-version certification, interoperability workshops, and the pattern where an example server built with a stack is certified rather than the stack itself.

   Asset The certification path for a real product, from self-test to logo

   8 min
9. 9
   Ask a vendor the right questions

   Six questions that separate 'supports OPC UA' from 'certified for the facets you need'.

   Asset A vendor questionnaire with the answers that should worry you

   7 min
10. 10
    Write your own conformance checklist

    Turning your project's requirements into a facet list you can test a candidate product against.

    Asset A requirements-to-facet mapping for an OEE collection project

    8 min
11. 11
    Test your own server before a lab does

    Self-testing with the CTT and the simulation servers, and the cheap checks that catch most of it.

    Asset A pre-certification self-test checklist with the results from a real server

    7 min
12. 12
    Know what certifies a person, and what does not

    The OPC Foundation certifies products, not people. What that means for hiring, for CVs and for this academy's own credential: stated plainly.

    Asset A written comparison of product certification, vendor training and this academy's credential

    5 min

Lab

Last verified 7 September 2026 against OPC UA 1.05.07. OPC UA Connect is an educational resource and is not affiliated with the OPC Foundation.