UNS vs MQTT: Why They’re Not the Same Thing

UNS vs MQTT: Why They’re Not the Same Thing

She wanted to rebuild everything on MQTT.

But her Unified Namespace was already there.

Had a conversation with an end user last week.

She came to me wanting to architect her PI System to use MQTT.

Why? Because that's what the conference told her.

"Everyone's doing UNS with MQTT."

But here's what I found when I looked at her actual setup:

• SAP — pointing to the cloud data warehouse
• CMMS — pointing to the cloud data warehouse
• ERP — pointing to the cloud data warehouse
• PI System — not connected

Her central place for everything already existed.

It was the data warehouse.

She didn't need to rebuild around MQTT.

She just needed to connect PI to what was already there.

This is the confusion I keep seeing:

UNS is a concept — a single source of truth where all systems connect.

MQTT is a protocol — one way to move data.

They're not the same thing.

Your UNS might be MQTT-based.
Or it might be a cloud data warehouse.
Or a historian.
Or something else entirely.

The question isn't "Should I use MQTT?"

The question is "Where does everything already point — and what's missing?"

In her case, there were 3 ways to get PI data into the data warehouse.

We picked the simplest one.

No MQTT. No rebuild. No over-engineering.

Just connecting what was already there.

Don't let conference buzzwords override your actual architecture.