A lot of industrial organizations are about to spend the next 20 years living with the wrong definition of "open."
They're procuring feature-level openness as if it were architectural openness, and the lifecycle behavior of those two systems is very different.
A system can support standard protocols, commercial off-the-shelf hardware, exposed APIs, and standard operating systems and still remain fundamentally vendor-defined. Applications can still be tied to specific execution environments. Lifecycle decisions can still follow vendor roadmaps. Upgrades can still occur as large, tightly coupled events.
That is openness as a feature set.
Open architecture changes the structure of the system itself. Components evolve independently. Applications move across conformant execution environments without modification. Interoperability is governed through defined interfaces and information models rather than custom integration. Lifecycle strategy shifts toward the operator instead of the vendor.
The distinction matters because the procurement process looks almost identical from the outside. Two vendors can both present "open" systems while delivering very different long-term outcomes. One produces another generation of tightly coupled lifecycle management. The other creates the possibility for incremental modernization over time.
That difference becomes very real around year 8 or year 12, when infrastructure refresh decisions start arriving and the plant discovers whether applications survive platform changes or have to be rewritten around them. In one environment, the operator is planning a phased infrastructure refresh while keeping existing applications intact. In the other, the plant is preparing for another major migration event tied to the platform lifecycle.
The questions that matter more than the marketing
If you're evaluating an OPA-compatible system, a few questions matter more than the marketing language:
- Can applications move across conformant execution environments without modification?
- Can components be replaced independently?
- Is interoperability achieved through standard architectural interfaces or custom integration work?
- Has the vendor demonstrated actual conformance testing?
Those answers tell you far more about the future lifecycle of the system than a slide claiming the platform is "open."
Operators are working through how to frame this procurement conversation in the OPA Community Forum, including what meaningful conformance evidence actually looks like in a vendor evaluation.