Industrial Automation

Ethernet Overtakes Fieldbus in New Node Counts. Should You Switch?

Nick Birk

We’ve been seeing the trend for the better part of a decade; but, according to the annual HMS Industrial Networks’ study, 2017 has become the milestone year in which Industrial Ethernet has, as ultimately expected, finally overtaken fieldbus in numbers of new nodes installed in factory automation applications.

This trend will no doubt continue. The operating efficiencies and productivity enhancements promised by the emergence of the Industrial Internet of Things—driven by the collection and strategic use of reams of real time data on the factory floor—are enormous. No doubt, most facilities—certainly nearly any manufacturing environment—must likely adapt or be left far behind. And that means enacting the speed, the bandwidth, the scalability, the universality and the flexibility of Industrial Ethernet.


Indeed, as more and more companies are finding out, now is an excellent time to do so. There are escalating numbers of Ethernet-enabled devices—even sophisticated robotics—to be had, and they are smarter, smaller and less costly than ever before.


Further, if you have been on the fence and waiting for a good time to make the switch, now just might be that time. Indeed, if you haven’t crunched the numbers in a while, you may be pleasantly surprised at how relatively cost effective it can be now, as compared to just a couple of years ago. And you may be impressed and excited by the capabilities of the newer devices that are within your reach.


Fieldbus Isn’t Going Away

So where does all this leave the fieldbus user?


Regardless of the trend, our research and experience shows clearly that there are many users who don’t see a need, at least in the short term, to migrate from fieldbus to Industrial Ethernet. Indeed, in our own customer research and conversations, many industrial decision makers even jokingly self-identify as “dinosaurs” or “laggards,” but truth is, what they have now works for them just fine.


Even the HMS study supports this experience. Yes, the total number of industrial Ethernet nodes has overtaken all others with 52% of the market, and the numbers demonstrate significant growth in 2017. However, fieldbus is still growing also—up by some 6% in 2017, according to the survey. And that growth rate is actually larger than the prior year’s. 


Further, if one looks at the different individual protocols under the Ethernet and fieldbus umbrellas, EtherNet IP has the largest market share with 15%, but, close behind, both PROFINET (Ethernet) and PROFIBUS DP (fieldbus) both boast 12% each. In other words, out of a dozen or so individual protocols called out, a flavor of fieldbus is tied for second. 


And why not? Fieldbus can inherently provide stronger inherent cyber-security—no small consideration in today’s environment. It can be even more reliable, as well as provide more deterministic performance. Further, not everyone operates in a data-rich manufacturing environment, so the Ethernet benefits might not so readily outweigh the legacy fieldbus capabilities for some types of operations. Factor in the necessary investment and the learning curve, and it becomes clear why it might make sense for some users to stay put for the time being—and even to go as far as upgrading and expanding their existing fieldbus networks.


The Choice Is Yours

The message to the supporting industries, companies such as Belden, should be very clear. We provide full support for our Ethernet customers, new and existing, and deliver industry leading expertise for those who will experience clear benefits by evolving from fieldbus, as can often be the case. However, for those who decide that changing to Ethernet is not yet the way to go, we are still very much in the fieldbus business.


Nevertheless, do keep in mind that no matter what type of operation you have, the trend is clear. Ethernet will continue to get better and even more cost effective, and there may well come a time where it makes sense for nearly every operation to strongly consider the migration. So continue to keep your ear to the ground, and be prepared to make a timely jump if and when it makes sense for your organization.


If you’re not sure, contact us. We understand application needs and network capabilities, and we can help you weigh the pros and cons. And, no matter what choice you make, fieldbus or Ethernet, let us know what’s working for you.