Thursday, October 29, 2009

Why I passed on Cat 6

In January of 2006 I was attending the winter Bicsi conference. Each time I go I always walk away having learned something new that I can bring back to my job. Just as important as the educational sessions are the opportunities to compare notes with my peers and see what’s new in the industry. That year it was each vendor’s new Category 6A cable. The IEEE had just passed the new 10GBaseT standards and the conference was buzzing.

I try not to be too cynical, but I couldn’t help but think of five years earlier when the TIA had finally approved the standards defining Category 6 cable. The conference had been buzzing then and I was a new RCDD fresh off my exam. I was riding high and ready to take my place among my more established colleagues.

No one was talking about the technical specifications of Category 6 UTP cabling: those had been relatively set for years. The bandwidth specifications were well known and the TIA standards were considered a bit overdue. The technical advantages were so obvious that they weren’t even discussed.

A few months later I was asked to be one of the principal authors of the new Univeristy of Florda Telecommunication Standards. And, surely enough, one of the questions that we needed to address was what minimum cable we would accept for new construction on campus. The older version of our standards required Category 5e cable. It almost seemed a forgone conclusion that we would require all new cable installed at the University of Florida be Category 6 UTP.

But, before making the change, I searched high and low for technical reasons to support the added expense. Now, I’m not an engineer, but I can read. I read every article, sales sheet, and white paper I could get my hands on. I was new to writing standards documents and I was earnest (and a little concerned) about doing a good job. Aside from technical differences between Category 5e and 6, I was looking for applications that required Category 6.

In the end, I could only find two advantages to installing category 6.

First, the additional bandwidth of Category 6 made it a much better medium for analog video traffic than Category 5e. This wasn’t an application we were very interested in. Our video needs were served very well by dedicated coax.

And second, 1000BaseTX, the new standard that was being trumpeted by the cabling manufacturers required Category 6 cable. 1000BaseTX was a hot topic at the conferences and seemed to be the principal argument for the installation of Category 6. But, 1000BaseTX only transported data at 1 Gigabit speeds, no faster than the already ratified 1000BaseT protocol. Pundits crowed that 1000BaseTX products would be cheaper and quickly dominate the electronics market. Unfortunately, 1000BaseTX products were incompatible with current 1000BaseT electronics. Watching the electronics market for a few months showed no great adoption of 1000BaseTX.

So, our first draft of the new UF Telecommunications Standard required only a minimum of Category 5e. This created quite a stir and I was called upon a number of times to defend the decision. This defense led to a number of spirited discussions at conferences and training events over the course of the next few years. I have enjoyed all of them and learned a great deal. None of them however, has changed my mind on the subject.

So, now I see the new standards for Category 6A in the process of being ratified. I hear words like futureproofing and emerging applications. I see a new IEEE specification that takes advantage of this amazing new cabling. I see everything I saw five years ago. So, while I applaud the creation of new technologies I have to wonder where I can best advise my employer to spend his money.

I’ll watch the electronics standards and see where the market moves: 802.11n looks interesting. Amazingly enough, 802.11n works fine with Category 5e cables.