100x faster: Gigabit Ethernet
Suppose I have three transportation choices. Average speed on the freeway is 10 mph, available technologies allow 100 mph travel, and one new option allows a 1,000 mph commute. Which would I choose for my 30-mile morning ride to work: 3 hours or 18 minutes or 1.8 minutes? I’ll take the under-2-minute commute, please. Thank you very much.
Oh, but wait. The fine print says not every place I need to go currently allows 1,000 mph (go figure). And I might have to pay for some equipment that would allow me through tollbooths at the highest velocity. But if the infrastructure works and is cost effective, doesn’t 1.8 minutes sound a lot better than 3 hours?
A first : Last month, the CC-Link Partner Association (CLPA) announced a Gigabit industrial Ethernet (IE) protocol, CC-Link IE, allowing network communications at near backplane speeds. The organization calls it the first open standard 1 Gigabit per second (1 Gbps) manufacturing network to be released globally.
Advantages? See the example above. Much of the existing highway will work if it’s Ethernet, namely standard IEEE 802.3z multimode fiber-optic cable in dual loop topology. Determinism is assured with network common memory without added hubs or switches, CPLA says. CC-Link IE also has:
Token-passing collision avoidance;
256k bytes network common memory;
120 stations per network capability;
550 m maximum cable length between two stations; and
Ability to handle 239 interconnected networks.
It’s part of a growing family. There’s CC-Link, which can connect controllers, and also CC-Link/LT for smaller devices; field and motion protocols are planned.
Disadvantages? You need appropriate equipment and connections that allow communications over fiber with CC-Link IE protocol.
The core technology was donated by Mitsubishi Electric Automation (as Rockwell Automation originally did with DeviceNet), so if your applications have Mitsubishi PLCs or other equipment that can communicate with this now open protocol, why not fulfill your need for speed?
Think ahead : 10 years ago, did anyone think we’d need the speed and power we have today? OK, if I’m just going to the ATM around the corner and neighborhood grocery, perhaps 1,000 mph is a bit over the top. On the other hand, I’d be sure to get the ice cream into my freezer before it melted, even on a rare 87-degree late October day—without accidents, guaranteed.
Learn more at www.cclinkamerica.org . Post your views (for this or anything in the issue) by going to www.controleng.com/archive , 2007, November. Look for the headline, click in, and use the tool provided to post a comment.
Here’s the math (a refresher for any fifth graders who happen along this way):
* 30 miles/10 mph = 3 hours, or 180 minutes;
* 30 miles/100 mph = 0.3 hours x 60 minutes = 18 minutes; and
* 30 miles/1,000 mph = 0.03 hours x 60 minutes = 1.8 minutes.