At Germany’s SPS trade fair in late November, the OPC Foundation announced its long-anticipated plans to extend OPC UA down to the field level. This announcement amounts to a breakthrough after a year-long stalemate that threatened to divide the industry into two competing camps. With the agreement of OPC’s member companies, that hatchet appears to have been buried, and a vision for the future of industrial networking is starting to emerge.
What reads like the launch of a new technical initiative is really a major breakthrough in industrial networking and the first step toward a single solution for industrial Ethernet. To address the rapidly growing data requirements in factories and process plants, our industry needs to move away from the current model of about six camps of “open-proprietary”, sometimes modified industrial Ethernet to a truly unified solution based solely on the IEEE 802.3 specification. By formally addressing the requirements of the field level with its Publish/Subscribe model, the OPC Foundation is breaking ground for a solution that in the future will supplant and eventually make obsolete current industrial Ethernet solutions. However, in the interest of protecting the installed based of industrial Ethernet devices, this process likely will take a generation to complete. Meanwhile, thanks to Ethernet’s support of multiple protocols, existing solution can continue to exist in parallel with the emerging, next-generation Ethernet solution for industry.
All current versions of industrial Ethernet are or soon will be implementing TSN, which unifies the mechanism for making Ethernet deterministic – a crucial requirement for industrial applications. By implementing OPC UA’s communications protocol both at the controller and field levels, automation suppliers in the near future can develop a single network interface for their connected products rather than a different version for each network.
Finally, the huge value of companion specifications implemented with OPC UA should not be underestimated. A companion spec is an information model for a device or a whole application that standardizes semantics and greatly speeds up integration. The widespread use of OPC UA will foster cooperation in the industry to share and codevelop an ever-growing library companion specs, from which all stakeholders will benefit.