FDT and OPC UA – Interoperability from Sensor to Cloud

Oct. 31, 2015
The FDT standard has a unique position in the automation architecture. It sits at the intersection of the variety of networks attached to intelligent devices and the higher level systems requiring interaction with the devices.

While the FDT standard is normally thought of as the enabling technology that allows interoperability across the variety of networks and devices, its position at this juncture makes it the secure central clearing house for topology, health, diagnostics, real time values, and other valuable information.

Architectures such as IIoT, and Industrie 4.0 crave access to information to which an FDT application has ready oversight. So how can we make this information more available across the enterprise? Enter another ubiquitous standard in our automation architectures – OPC UA (Unified Architecture). The OPC UA standard provides the secure and reliable exchange of data between client applications. The FDT Group and the OPC Foundation have been collaborating to provide off-the-shelf interoperability between these two great standards. Our joint technical working group committee has released a substantial body of work to the two organizations – it is my pleasure to give you a brief preview.

The FDT standard incorporates the notion of a plant hierarchy based on the physical network topology as well as a logical topology. The network protocols in the industry; as known to the FDT standard, allows an FDT enabled Frame Application to talk with any device. This includes the ability to transparently tunnel through any number of disparate networks to gain access to the end device. Beyond normal real time data, the FDT interface application also has access to commissioning, diagnostic, prognostic, and other higher level data. To make these rich data sources available to an OPC UA architecture, the data has been mapped to the OPC UA data model to present it in a standardized fashion. The FDT Frame or host application is then configured as an OPC UA server.

OPC UA based applications that wish to gain access to the information available from the FDT OPC UA server take on the characteristics of an OPC UA client. The client requests a secure connection with the FDT OPC UA server and begins to access topology, health, real-time, and other data from the well-connected FDT UA server. Any number of clients may gain access, limited by the capacity of the server and underlying network bandwidths.

It is interesting to think about the possible applications for the OPC UA client that is connected to the FDT Frame or host system. Consider an off-the-shelf OPC UA client mobile app that can be deployed on an Android or IOS based device. The user can then take their tablet, pad, or mobile phone into the field or onto the plant floor to gain access to device information critical to keeping the application running or bringing it back on line in an expeditious fashion. All of this is possible without any custom code or other applications thanks to the well defined interfaces between FDT and OPC UA. Of course the OPC UA client can also be bolted on or built into higher level applications to provide previously unrealized access to real time information.

While the FDT OPC UA server has been depicted so far as a source of information, the combination of the FDT standard and the OPC UA standard also allow the FDT Frame or host to receive information via the OPC UA client. This opens up the possibility of an OPC UA enabled commissioning or diagnostics tool to set values in the intelligent device without bothering with network cards, protocol stacks, and network topology, for example. Devices can be referenced from the FDT plant topology and have appropriate settings updated with the swipe of a finger.

Security in an interconnected architecture is a front and center topic that our architects have taken into consideration. While IIoT and Industrie 4.0 will bring more requirements and specificity to the topic, the current architecture supports authenticated and encrypted communication channels between the FDT Frame and the OPC UA client. The FDT role based security provides an additional level of authorization required for the various layers of the workforce in a typical customer environment. As additional standards and requirements emerge, we will continue to enhance our security posture.

Our next step in the melding of these two great standards is to integrate this body of work into our developers’ toolbox known as FDT Frame Common Components. This will provide a highly engineered and well tested engine that can be easily deployed in all off-the-shelf FDT enabled products. Stay in touch with your automation supplier to take advantage of this lush source of portable information from your existing automation architecture.

A joint press conference and demonstration by the OPC Foundation and the FDT Group is scheduled at the upcoming 2015 SPS Fair press conference on Wednesday, 25 November at 10:00 in Room Prag (NCC Ost, Level 2). Join Glenn Schulz of the FDT Group and Tom Burke of the OPC Foundation as they demonstrate the seamless interoperability of FDT with OPC UA from the sensor to the cloud. Visit the FDT Group on the tradeshow floor, located in Hall 2, booth 550. We look forward to seeing you there.

Lee Lane

Chairman of the FDT Group Board of Directors

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