Many Flavors of Ethernet

May 8, 2008
Talking about using Ethernet on the factory floor or in the canyons of metal that constitute a process plant was almost revolutionary when we first covered it in the Industrial Automation Review in February 2005.

While we can’t say that this ubiquitous networking technology can be found everywhere in manufacturing, it is no longer surprising to hear of an engineer seriously considering it for the next project—or even for a retrofit.

When our series Editor Terry Costlow went out for research for this piece, the surprising element was all the varieties of Ethernet that he found. While some companies prefer to use “standard” Ethernet, meaning the common protocol stacks and physical layer used in business and home networks. Others have tweaked the stack in one way or another in order to optimize it for a particular set of applications, or perhaps to gain a competitive advantage rather than use a network favored by a rival.

These differences lead to a variety of arguments about who is truer to the standard, or whose network requires “proprietary” hardware or firmware. These debates may be entertaining to editors, but they can be downright confusing to engineers trying to figure out the best way to implement a new project. So, that is what Costlow is trying to do with this series—shed enough unbiased light on the topic to show you how people are applying the technology. If you have a good application and you would like to show off your expertise a bit, send us a note. We’ll consider it for a future issue.

Speaking of networking, check out the Automation World Webcast on wireless networking for industry, in which Ron Helson of the Hart Communication Foundation clearly describes WirelessHart, at