What Should I Do about TSN?

TSN = Time Sensitive Networking. It’s a catchall name for a series of new standards whose goal is to improve determinism in “standard” Ethernet networks. It grew out of the needs of Audio/Visual delivery. Naturally, a new organization grew to further the effort: “The Avnu Alliance is a community creating an interoperable ecosystem servicing the precise timing and low latency requirements of diverse applications using open standards through certification.” Someone pointed out to the organization that industry had the same needs. So industrial consortia and industrial companies jumped into the standardization effort. Hence “diverse applications” is now the focus. The effort is ongoing. Some of the standards are complete and some are in draft. But the efforts are far enough along for demonstrations and preliminary products.

There are lots of articles in our trade press touting TSN. Here’s what users of PROFINET have to do to prepare: Nothing!

PROFINET uses Standard Unmodified Ethernet. Typically, with wired 100Mbit/s infrastructure, but it’s just Ethernet. So gigabit Ethernet is fine for PROFINET. Multi-gigabit Ethernet is fine for PROFINET. Wireless is fine for PROFINET. Fiber instead of copper is fine for PROFINET. TSN is fine for PROFINET.

The good thing about PROFINET building on a broadly adopted commercial standard like Ethernet is that we get to ride the evolution to higher speeds and other features.

But wait you say, you need the synchronization and speed of TSN and you need it today. There is no need to wait; PROFINET already provides IRT for just those needs. TSN may provide comparable performance someday; emphasis on “may.” There are some other unknowns with TSN. Configuration is required. How will that be done?  If it’s “just 700 easy steps” as one of our members that’s involved in the effort observed, the promise may be difficult to realize. Whatever it takes though, PI will try to make it easy for the user.

If you think that TSN replaces PROFINET you’re forgetting that TSN is just part of Ethernet and Ethernet is not a protocol… as I blogged long ago in “Ethernet is not a Protocol.”  No matter what Ethernet looks like (TSN included), you still need an application layer program to make a whole solution.

In conclusion, there is nothing you have to do about TSN. When the time comes, PROFINET will use it just like it uses standard Ethernet today. And if you need synchronization, speed, and determinism today PROFINET IRT does that now.

–Carl Henning