Data Communication for Industrial IoT – Conclusion
The Industrial IoT holds a lot of promise for improving productivity and cutting costs for industrial systems. Yet the IIoT is different from both the consumer IoT and traditional SCADA systems. In particular, data communications have unique requirements that you need to keep in mind if you are planning to implement an IIoT project that works well.
Because industrial data communication was developed independently of the Internet, the merging of these two technologies requires a re-thinking of some basic assumptions. The most secure and reliable approach is to focus on the data, and to allow access to the data only. Accessing a device means that the device is open to an attack. Accessing the network leaves the network exposed, even if you use a VPN. A more secure-by-design approach allows the data source and the data user to make outbound connections to a public or private cloud service that holds only the data. This keeps all plant firewall ports closed, and provides a secure spot independent of the plant where the data can be accessed by authorized users.
Data Protocol Problems
A number of data communications protocols have been proposed for the IIoT, each with its advantages and drawbacks. UDP works for VOIP and streaming media, but it lacks the accuracy and completeness so necessary for good industrial communication. MQTT offers a publish/subscribe mechanism and many-to-many connectivity, but lacks a standard data protocol and the ability to handle messages intelligently. OPC UA is a good choice for in-plant connectivity, but suffers from the traditional server/client design that requires an open firewall port to connect from the Internet. REST over HTTP is popular for general IoT applications, but has issues with bandwidth, latency, scalability, symmetry, and robustness when faced with the high speed and large number of connection requirements of the IIoT. To implement security Blockchain may sound good in theory, but a closer look shows why it will fail in practice.
A New Approach
Clearly, a new approach specifically designed for IIoT is needed. This approach should use the robust foundation of TCP, the security of a publish/subscribe model like MQTT, and the in-plant connectivity of OPC UA. Its bandwidth use, latency, and scalability should far exceed RESTful HTML. This new approach should support edge processing, and in fact, provide the means for edge processing, cloud processing, and fog processing, as dictated by the circumstances on the ground or in the field. It should be available as a public cloud, a private cloud, or a hybrid combination of public and private clouds.
Something That Actually Works
Most important, this approach should actually work. You should be able to install it in greenfield or brownfield projects. It should connect to existing systems, use open protocols, and provide secure, robust, real-time performance at speeds not much slower than Internet propagation speeds. And it should be available today, right now. If you’re interested, give us a call.
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