What is the first step that the Industrial Internet must take?

As we all know, Ethernet has become the most widely used communication protocol standard for home, enterprise and data center network connection and intercommunication. However, due to its determinism, real-time, reliability and other factors, traditional Ethernet is not suitable for industrial data communication. For example, the CSMA/CD mechanism of Ethernet requires continuous retransmission of data when a network conflict occurs, which poses a challenge to the real-time performance of the network; in addition, the reliability of Ethernet is greatly reduced due to the harsh working conditions and serious line interference faced by industrial sites.

Therefore, because Ethernet was not designed for industrial network applications, major manufacturers in the industrial control field have developed industrial Ethernet protocols suitable for their own industrial control products, such as Siemens' Profinet, Schneider's Modbus TCP/IP, Rockwell's Ethernet/IP, EtherCAT, Powerlink, CC-Link, etc. Compared with traditional Ethernet and fieldbus, industrial Ethernet has obvious improvements in real-time performance and transmission rate.

However, these proprietary industrial Ethernet protocols still face bottlenecks, although they are more than sufficient to meet the needs of machine motion control and other aspects.

Because when cloud computing and big data technologies gradually penetrate into the industrial field, industrial data communication is no longer limited to the machine-to-sensor layer, nor is it limited to machine-to-machine, but has expanded to richer connections with people, clouds, and applications. There are more types and more massive amounts of data that need to be transmitted and processed, and the chain for data processing has become longer, including on the edge side, in the cloud, and gradually connected with the enterprise production system and management system. Therefore, how to deal with the connection and transmission of massive data through higher bandwidth, and how to achieve more precise deterministic control and lower latency, are still huge challenges for industrial manufacturing. Therefore, a communication protocol that breaks fragmentation and a unified data link service standard are more important for the future of industrial manufacturing.

The “unification” of industrial data communications

TSN (Time Sensitive Network) + OPC UA (OPC Unified Architecture) have become the perfect partners for establishing a comprehensive communication infrastructure from sensors to the cloud.

TSN works on the principle of priority application (IEEE P802.3br) mechanism, giving priority to critical data packets during transmission. This means that critical data does not have to wait for all non-critical data to be transmitted before starting, thus ensuring a more certain and faster transmission path. In essence, TSN establishes a new set of standards that make Ethernet real-time and deterministic.

Based on the high certainty and low latency of network communication provided by TSN, OPC UA provides a platform-independent service-oriented architecture that defines unified standards and information models to enable interaction between devices, devices and enterprises, and devices from different manufacturers.

The combination of TSN+OPC UA provides a real-time, highly deterministic communication network that is truly independent of device manufacturers, which will bring huge improvements in bandwidth, security, interoperability, latency and synchronization.

For example, in factory data collection, transmission and production operations, it is necessary to collect on-site machine status, production energy consumption, quality-related and production-related parameters. With TSN+OPC UA, data can be directly connected to the cloud without going through PLC controllers, SCADA systems, MES systems... As a unified format for data transmission, OPC UA can be deployed at both the sensor layer and the cloud platform layer to maintain the unity of the full-stack information model.

In other words, TSN+OPC UA completely unifies the service standards of data links, just like Qin Shihuang unified weights and measures, which means that it completely unifies nearly 100 fragmented communication protocols in the industry. A unified and effective data structure contributes to the development of a digital society no less than Qin Shihuang's move of "unifying the writing system and the track of vehicles". After achieving this great unification, it will inevitably cause a series of subversive chain reactions. The pyramid structure of traditional industry will most likely be directly broken and turned into a flat structure. Data acquisition can directly "skip" to data analysis and application without going through layers of equipment.

TSN+OPC UA seamlessly integrates IT and OT

Of course, the application of the TSN+OPC UA combination in the industrial field is still in its infancy, and more and more industrial suppliers, ICT manufacturers and chip suppliers are also jointly accelerating its testing and verification.

At the just-concluded 2018 Hannover Industrial Fair, many organizations and manufacturers jointly launched a test and verification for TSN+OPC UA scenario applications. More than 20 international organizations and well-known industry manufacturers, including the Alliance for Industrial Internet (AII), Avnu Alliance, Edge Computing Alliance (ECC), Fraunhofer FOKUS, Huawei, Schneider Electric, Hollysys, National Instruments (NI), B&R, TTTech, Spirent Communications, etc., jointly released the TSN+OPC UA intelligent manufacturing test bed covering six major industrial Internet scenarios.

Dr. Alexander Willner of Fraunhofer FOKUS, Europe's largest applied scientific research institute, said, "Since the advent of programmable logic controllers (PLCs), industrial automation processes have been greatly optimized. The convergence between OT (operational technology) and IT (information and communication technology) is exciting and will bring interesting innovative experiences. The combination of OPC UA and TSN enables real-time information exchange and interoperability in the industrial field. The scenarios demonstrated in the joint test bed show the advantages of our respective technologies, and we are full of expectations for the future of digital networks."

In the past, from the field layer, control layer to the information layer, the best solution was to use products from similar suppliers for easy integration and penetration. But now, the "artificial boundaries" caused by competition among enterprises have shown signs of being broken, because no matter how different the product types, brands, functions, etc. are, they can be easily penetrated and integrated from bottom to top.

Of course, the industry’s pursuit of TSN+OPC UA is not simply because of the high reliability and real-time performance it brings. More importantly, they have truly opened the door to the transformation to smart manufacturing by rewriting the underlying architecture of industrial communications.

Whether it is Germany's "Industry 4.0" or China's "Made in China 2025" strategy, the technical foundation behind them is the opening of the Internet of Things. TSN+OPC UA is the key to connecting the last kilometer of industrial interconnection, and is also the key to truly realizing OICT integration and accelerating intelligent manufacturing.

TSN+OPC UA will accelerate the formation of mature industrial Internet applications and production systems by changing industrial data communications because it ensures unimpeded data flow.