So why is time-sensitive networking so important for embedded this year? We address this directly in our TSN keynote at NIWeek 2016 last fall. Here’s an updated transcript of that keynote, featuring our own Jamie Smith and Todd Walter, Intel’s Kevin Stanton, and Cisco’s Paul Didier. You can also watch the keynote above.
The systems driving the Industrial Internet of Things (IIoT)
Smith: Over the past few years we’ve been working with many of you to develop complex distributed control and monitoring system - systems making the grid smarter, improving the uptime of power facilities, keeping the trains running on time, and controlling complex machines. All of these systems are based around our platform, using advanced I/O processors and FPGAs, and your algorithms written in LabVIEW. These systems are then networked together with a variety of technologies and protocols to manage them and extract insights from them as big analog data solutions.
These systems are playing a critical role in building the IIoT. And as we’ve worked together to build them we’ve learned that there’s an even bigger need to bigger data access - data that can flow more easily between our controllers, all the way from the I/O pin to the cloud and across industry boundaries that have historically been silos.
A roadblock for the IIoT: non-converged networks
Stanton: We still predominantly see non-converged networks. We see IT networks, connecting people at home or at work, and we see OT networks controlling machines, connecting plants and grids to each other. The cables and connectors in these networks may look the same, but the objectives and underlying technologies are quite different. To deliver the promise of the IIoT, we need to converge OT networks and the IT infrastructure.
The solve: time-sensitive networking (TSN)
Walter: To demonstrate this we demoed a small network at NIWeek 2016 with 4 CompactRIOs, connected through a network of ethernet. We controlled with one CompactRIO-controlled motor disk and then sent commands/position data to the other three.
Everything looked synchronised and coordinated using a standard IT network, with no problems. But with the issue of convergence: meaning when we mixed this flow with other OT infrastructure and data flows, we began to see problems with control frames coming from the first CompactRIO being delayed past their deadline, or being dropped entirely. If this had been a real machine, this interruption could have damaged the machine or the parts it was making.
Smith: Historically, this is why OT and IT networks have been kept separate.
Didier: We worked on a way to converge the two successfully, using TSN - which allowed IT and OT data flows to flow together in a converged network undisturbed.
The foundation of this converged networking technology is TSN - an evolution of ethernet standards created by the IEEE 802 standards committees. We’ve all been collaborating to enhance ethernet with deterministic operations required by OT systems.
Stanton: Using TSN we’ve enhanced networking so the time performance has improved dramatically.
Three primary capabilities of TSN
Stanton, Didier, Walter: We’ve accomplished these improvements by adding there main capabilities:
Precise time synchronization: accomplished via a standard of IEEE 802.1as, based on 1588, the precision time protocol that’s been around for about 10 years.
Traffic scheduling: Combining time synchronization with traffic management, to deliver latency guarantees. Each switch identifies the time-critical data and places it in a special queue. The pitch then forwards each of these packets at very specific times. This creates a network flow where a virtual wire between the talkers and the listeners across the entire network.
System configuration: Taking a page out of software-defined networking (SDN), this abstracts the network configuration from the end application configuration.
Why LabVIEW’s such a huge asset for TSN
Didier: LabVIEW requests reservations of the network by specifying which data is time-critical, which nodes need to receive that data, and how long it needs to take to get there. Then, in SDN-fashion (software-defined networks), network management will evaluate the network, will create the schedules and the routes, distribute that to the network infrastructure, then provides LabVIEW with network and timing parameters.
Smith: Our customers are well-poised to take advantage of this tech, specifically because they’re already using LabVIEW - and LabVIEW, for years, has had constructs that base their execution on time, whether it’s the time loop in LabVIEW Real-Time or the single-cycle time loop in LabVIEW FPGA.
What we’re doing with TSN at Embedded World 2017
Panel: “Theory of Operations for TSN-based Industrial Systems and Applications,” 16 March 2017 from 09:30-10:00.
Our booth, where you can learn more about the next evolution of the Ethernet standard (TSN) and find out what this means for your future applications: Hall 1, booth 652