🤖 IIoT vs SCADA: Differences and How to Connect Old CNCs
1. What is IIoT? (Industrial Internet of Things)
IIoT is a network of connected sensors, devices and machines in industrial environments using Internet of Things technology to transmit data.
Objective: Focus on Big Data , Predictive Analytics and independent decision making.
Architecture: Often uses a decentralized and cloud-driven architecture , with devices communicating over the internet or edge computing.
Protocols: Use modern open protocols such as MQTT , AMQP .
2. What is SCADA? (Supervisory Control and Data Acquisition)
SCADA is a large-scale industrial control and data acquisition system that has been in use for decades.
Objective: Focus on real-time control and monitoring, especially mission-critical processes such as power plants and water treatment systems.
Architecture: Uses a centralized architecture with a main server controlling the local PLC (Programmable Logic Controller) or RTU (Remote Terminal Unit).
Protocol: Use industry-specific proprietary protocols such as Modbus, Profibus, or OPC UA.
💡 Key differences between IIoT and SCADA
| Points of comparison | SCADA (traditional) | IIoT (Modern) |
| architecture | Centralized, On-premises | Decentralized and Cloud-Driven |
| Main objectives | Real-time control and monitoring, alerting when problems occur | Deep data analysis , predictive maintenance |
| Connection | Mostly wired, focusing on local networks. | Use wireless (Wireless), focus on open networks (Internet) |
| protocol | Industry-specific protocols (e.g. Modbus, OPC UA) | Open Internet protocols (e.g. MQTT , JSON) |
| Access to information | Data resides in specific silos, with limited access. | Data is translated to be easily readable and accessible for Big Data Analytics. |
🔌 Connecting traditional CNC machines with IIoT systems
Legacy CNC machines often do not have the ability to connect directly to the internet or use modern protocols, so IIoT requires gateway devices to extract data:
Protocol Conversion Gateways:
The gateway acts as a middleman to communicate with the CNC machine using existing protocols (e.g. RS-232, Modbus) or directly connect to the PLC/Controller.
The gateway then translates that machine language data into a format the IIoT platform can understand, such as the MQTT protocol , and sends the data to the cloud or server for analysis.
External Sensors & Edge Devices:
For machines without any communication ports, additional external sensors such as vibration, current, or temperature sensors can be installed to assess the operating status (Run/Stop/Idle) and condition of the machine.
Edge devices collect data from these sensors, perform preliminary processing, and transmit it to the IIoT Platform.
Using IIoT in this way allows factories to extract valuable data (such as machine status, uptime, OEE data) from old machines for analysis and efficiency improvement, without having to invest in replacing the entire machine.
| Core technology | IIoT , SCADA , Industrial IoT , Industrial Control System, Industry 4.0, Digital Transformation |
| difference | IIoT vs SCADA , IIoT SCADA Differences, System Architecture, Real-Time Monitoring, Big Data Analytics |
| architecture | Cloud-Driven, Decentralized Architecture, Centralized Architecture, Edge Computing, PLC, RTU |
| Connection | Legacy CNC machines , Legacy machine connectivity, Gateway Devices , Protocol Conversion, External Sensors, Connectivity |
| protocol | MQTT, OPC UA, Modbus, Industrial Protocols, Open Protocols, Communication Protocols |
| objective | Predictive Maintenance , Process Control, Operational Technology (OT) |
IIoT
SCADA
Legacy CNC
Connecting old machinery
IoT in industry
