Case study · Industry 4.0
Unified Namespace in an ISA-95 context
Replacing a frozen, point-to-point shop-floor integration with one governed MQTT namespace: new machines in days, data you can trust, no supplier lock-in.
- Scope
- Shop floor ↔ ERP ↔ MES
- Standard
- ISA-95 hierarchy
- Role
- Architecture, integration, security
- Duration
- 18 months
14
heterogeneous assets in one namespace
0
existing assets reconfigured per new integration
5
governance pillars
6
industrial use cases enabled
The need
The line ran on a centralised platform whose vendor had closed down. Every machine was wired to it with custom logic: nobody could extend it, and adding one machine meant touching what already worked.
On the floor, that means slow changeovers, orders and statuses living in different tools, and data nobody can trace back to a machine or an order. The goal: one place where every asset publishes, and every system reads.
Constraints and decision
| Constraint | Options | Decision |
|---|---|---|
| Vendor closed, platform frozen | Patch the legacy · buy a UNS suite · open stack | Open MQTT broker and open tooling |
| Machines can’t be modified, protocols differ | Rewrite PLC code · native MQTT · gateway per asset | One gateway per asset, in front of each machine |
| Production must not stop | Big-bang cut-over · progressive migration | New sub-tree per asset, legacy keeps running beside |
| Data must be readable and trusted | Raw registers · Sparkplug B · plain MQTT + JSON | ISA-95 topics, context carried in the payload |
| A shared broker is a shared risk | Flat network · passwords only · layered security | mTLS, ACL per client, MQTTS, OT/IT segmentation |
Architecture
Data platform
Edge / shop floor (OT)
- IIoT OT + sensors
- IoT + IT systems
- ERP & SaaS services
MQTT broker
- Hierarchical namespace · mTLS · ACL
Processing
- MQTT collection
- Transformation hub
Storage
- Time series
- Traceability
- Product passports
- Data warehouse
Consumers
- Dashboards
- BI
- API
- Applications
- AI
Unified Namespace, layer by layer
Field & control (OT)
- Mobile robot
- Pick-to-light
- Cobot
- SMT line
- Digital I/O
Gateways
- One per asset
- Protocol → MQTT
- Publish to /edge/
UNS core
- MQTT broker
- Edge → functional flows
Integration services
- Cloud MQTT bridge
- Workflow automation
Business systems
- ERP
- MES
- Cloud applications
One tree, readable by anyone
Topic · site / area / line / asset / data
plant/assembly/mobile/transport/amr_01/location
Payload (illustrative)
{
"ts": "2026-02-01T09:14:22Z",
"schema": "v1",
"asset": "amr_01",
"status": "running",
"source": "gateway-amr",
"comm": { "quality": "GOOD" },
"last_ok": "2026-02-01T09:14:22Z"
}- Standardisation
- Ownership
- Traceability
- Lifecycle
- Versioning
From customer order to assembly
- 01Customer order configured on the web configurator
- 02ERP creates the order and publishes it to the UNS
- 03MES receives the manufacturing order
- 04Operator presses a button; the MES triggers the pick-to-light
- 05Assembly starts; each step updates the order status
- 06Test station posts its result; the order is closed
Edge first
Raw data lands under /edge/, flagged as not contextualised. Only flows up once cleaned.
Report by exception
Publish on change, deduplicated: information, not noise.
Two scenarios, one broker
Historical and new production flows coexist without interfering.
Result
Add a machine, not a project
Five integrations, each a new gateway and a new sub-tree. Nothing existing was touched.
One source of truth
Orders, statuses and machine data share one namespace, readable by IT and OT alike.
Traceable by design
Every message carries source, time and quality, so a value can be trusted or challenged.
No lock-in
Open protocols and replaceable components: the next vendor closure is not a crisis.
Integration timeline
Nov 2024
Mobile robot
Jan 2025
GeoLoc
Mar 2025
Cobot
Jun 2025
SMT line
Sep 2025
Second MES
Not proven yet
- No ROI measured: no production KPIs (OEE, scrap, cadence).
- No operator adoption study.
- Single broker instance: resilience not yet tested.
What I learned
Governance outlives the broker
Naming, ownership and topic lifecycle decide whether a namespace stays usable.
Context at the source
Adding it once in the gateway is cheap; rebuilding it in every consumer never ends.
Security on day one
Easy with two clients, painful with twenty.
Say what you didn’t prove
Stated limits make the work easier to trust.
Let’s build what runs next.
Open to Industrial Digital Transformation & Cybersecurity Engineer roles