Node-RED
Node-RED is an open-source flow-based development platform for visually connecting systems, protocols, applications and devices through logical data flows. The platform is widely used for integration, automation, Edge Computing, IoT solutions and industrial data exchange.
Within OT and industrial automation environments, Node-RED is increasingly applied as a flexible middleware layer between PLC, SCADA, cloud platforms, data sources and IIoT systems.
Node-RED supports rapid development of:
- Data flows
- Protocol conversions
- Alarm flows
- Dashboards
- API integrations
- Edge analytics
- OT integrations
The platform therefore plays an important role within modern IT OT Convergence architectures.
⚙️ How Node-RED works
Node-RED operates on the basis of visual flows.
A flow consists of connected nodes that receive, process and forward data.
Basic architecture:
- Input node receives data
- Function nodes process logic
- Output nodes send data
- Dashboard or storage nodes visualise or persist information
A flow can, for example:
- Retrieve PLC data
- Transform data
- Generate alarms
- Send data to cloud platforms
- Provide historical storage
Node-RED runs on top of Node.js and uses JavaScript for logic and scripting.
🏭 Applications in Industrial Automation
Within Industrial Automation, Node-RED is used for rapid integration of OT systems.
Protocol conversion
- Modbus TCP to MQTT
- OPC UA to REST API
- Serial communication to cloud platforms
Data aggregation
- Collecting sensor values
- Combining historical data
- Centralising alarm streams
Machine monitoring
- Production status
- Energy consumption
- Cycle times
- OEE data
SCADA extensions
- Web dashboards
- Notification systems
- Event handling
- External integrations
Edge computing
- Local analysis
- Filtering
- Buffering
- Data reduction
🧠 Flow-based programming
Node-RED uses a visual programming model.
Key node types:
| Node | Function |
|---|---|
| Input | Receives data |
| Function | Processes logic |
| Output | Sends data |
| Dashboard | Visualisation |
| Storage | Storage |
| Trigger | Event-driven |
Flows are built using drag-and-drop.
Examples of integrations:
This enables rapid OT integration without complex software development.
🌐 Supported protocols
Node-RED supports a large number of IT and OT protocols.
Frequently used OT integrations:
| Protocol | Application |
|---|---|
| MQTT | IIoT messaging |
| OPC UA | Industrial data |
| Modbus TCP | PLC communication |
| SNMP | Network monitoring |
| HTTP/HTTPS | API integrations |
| WebSocket | Real-time communication |
In addition, Node-RED supports:
- SQL databases
- REST APIs
- Cloud services
- Filesystem integrations
This allows Node-RED to function as a protocol gateway within industrial networks.
📊 Dashboards and visualisation
Node-RED supports simple dashboards via dashboard nodes.
Typical visualisations:
- Charts
- Status panels
- Gauges
- Alarm overviews
- Buttons
- Trends
Within OT, dashboards are used for:
- Local monitoring
- Machine visualisation
- Energy analysis
- Prototyping
- Edge HMIs
For more complex visualisations, Node-RED is often combined with Grafana.
🔄 Integration with PLC and SCADA
Node-RED is regularly used as a flexible integration layer alongside traditional automation systems.
Typical integrations:
| System | Function |
|---|---|
| PLC | Process data |
| SCADA | Monitoring |
| Historian | Historical storage |
| HMI | Visualisation |
| MES | Production data |
Applications:
- Non-standard integrations
- Cloud connectivity
- Data enrichment
- Alarm forwarding
- API exposure
Node-RED usually does not replace SCADA, but supplements missing integration functions.
⚡ Edge computing and IIoT
Node-RED is popular within Edge Computing due to its low system load and flexibility.
Frequently used edge applications:
- Local filtering
- Offline buffering
- Protocol translation
- Event processing
- Local dashboards
Within the Industrial Internet of Things, Node-RED often functions as an edge gateway between OT Assets and cloud platforms.
Advantages:
- Low hardware requirements
- Fast deployment
- Broad protocol support
- Good extensibility
📈 Data processing and event handling
Node-RED supports real-time event processing.
Examples:
- Alarm detection
- Threshold monitoring
- Data normalisation
- Aggregations
- Workflow automation
Event-driven architectures are important within:
- Smart manufacturing
- Predictive Maintenance
- Energy management
- Unified Namespace
Node-RED is therefore often combined with MQTT brokers such as Mosquitto.
🧩 Integration with databases
Node-RED supports storage of industrial data.
Frequently used databases:
| Database | Application |
|---|---|
| InfluxDB | Time series data |
| PostgreSQL | Relational storage |
| MySQL | Production data |
| MongoDB | Flexible data |
This allows Node-RED to act as an ETL layer between OT systems and analytics platforms.
🔐 Cybersecurity of Node-RED
Because Node-RED frequently connects to both IT and OT systems, significant Security challenges arise.
Risks:
| Risk | Consequence |
|---|---|
| Open dashboards | Unauthorised access |
| Weak authentication | Compromise |
| Insecure flows | Data manipulation |
| Remote code execution | System takeover |
Key controls:
Within OT, Node-RED must be carefully positioned within segmented architectures.
Direct access to critical PLCs from IT networks is generally avoided.
🚨 Availability and reliability
Node-RED is regularly used in semi-critical OT processes.
Key considerations:
- Flow backups
- Configuration management
- Logging
- Monitoring
- Redundancy
Failure scenarios:
- Hung flows
- Memory leaks
- Overload
- Lost broker connections
- Faulty scripting
For these reasons, Node-RED is usually not used for hard real-time control or safety-critical functions.
⚠️ Limitations in OT
Although Node-RED is highly flexible, limitations exist.
| Aspect | Limitation |
|---|---|
| Hard real-time | Not suitable |
| Safety control | Unsuitable |
| High availability | Additional measures needed |
| Lifecycle management | Complex in large deployments |
| Governance | Risk with uncontrolled flows |
In production environments, Node-RED is therefore often used as a supplementary integration and data layer.
☁️ Cloud integration and hybrid architectures
Node-RED supports cloud connectivity with:
- Azure
- AWS
- Google Cloud
- REST platforms
- MQTT cloud brokers
Applications:
- Central monitoring
- Multi-site analytics
- Energy dashboards
- Predictive maintenance
Within critical infrastructures, cloud integration is often restricted by Compliance and security requirements.
🔄 Node-RED versus traditional middleware
| Property | Node-RED | Traditional middleware |
|---|---|---|
| Development speed | High | Lower |
| Flexibility | High | Medium |
| Visual programming | Yes | Usually no |
| Hard real-time | No | Sometimes |
| Enterprise governance | More limited | Stronger |
| OT-native | Partially | Variable |
Node-RED excels particularly in rapid OT integration and prototyping.
🏗️ Node-RED in IT/OT convergence
Within IT OT Convergence, Node-RED often functions as a flexible orchestration and integration layer between IT and OT systems.
Applications:
- Unified Namespace
- Edge analytics
- Asset Monitoring
- Protocol conversion
- Data orchestration
- Cloud integration
Node-RED supports modern industrial initiatives such as:
At the same time, large-scale deployment requires attention to:
- Governance
- Security
- Lifecycle Management
- Standardisation
- Change Management
Node-RED thus represents an important platform within modern industrial edge and integration architectures.