The edge device

The edge device is the device which enables the I-IoT. It is physically located in the factory and is linked from one side to the industrial data sources through the OPC server, and from the other side to the cloud through the IoT gateway. There is much debate about the location, role, and responsibilities of the edge device. With regard to the I-IoT, it must have the following minimum capabilities:

  • Implement OPC client interfaces (both OPC Classic and OPC UA) to gather the data from the industrial data sources, which include PLCs, DCSes, SCADA, and Historians
  • Have OPC Proxy functionalities to manage indifferently the incoming data requests following both OPC Classic and OPC unified interfaces and addressing them accordingly
  • Implement bi-directional communication to the cloud through VPNs, SSLs, or cellular lines through the most common internet application protocols such as Message Queuing Telemetry Transport (MQTT), Advanced Message Queuing Protocol (AMQP), and Hypertext Transfer Protocol Secure (HTTPS) to:
    • Transfer the data to the cloud through the IoT Hub
    • Receive commands and configurations from the IoT Hub
  • Implement a store and forward mechanism to guarantee the data transfer along the communication channel in case of a poor, intermittent, or overloaded connectivity
  • Expose centralized functionalities available from the cloud. These include the following:
    • Setup and monitoring of the device
    • Data acquisition parameters and configuration deployment
    • Software patches and software upgrade deployment
  • Be available both as a physical and a virtual appliance
  • Be multi-platform (at least on Windows and Linux)
  • Be flexible and scalable to support the collection and transfer of anything from several hundred tags to dozens of thousands of tags

Additional capabilities of the edge device might include:

  • Capturing, storing and processing of the buffer with high frequency data (from 1 Hz to 20 kHz)
  • Implementing drivers for the most common control bus protocols (PROFINET, EthernetIP, and Modbus)
  • Implementing an analytics engine to detect anomalies and/or locally processing high frequency data related to the transient or high dynamic phenomenon
  • Implementing an Advanced Process Control (APC) to analyze the process and optimize it autonomously, sending the suggested outputs to the controllers
  • Implementing a Trusted Platform Module (TPM) to improve cybersecurity