As surprising as it may seem to anyone who has visited my flat, I can be obsessed with tidiness, at least when it comes to patch panels and server racks. I like patch cords dressed and tucked out of the way, and I have been known to slap a label on anything that stays in one place for more than a few minutes. In our case, this neatness also tells visitors that we run a tight ship, and gives them a sense of confidence that we know what we’re doing when we test their products.
When the ZDE San Francisco branch moved to new offices at the end of last year, I wasn’t around for the very first round of unpacking, being on a trip back East. Since the first of the year, I’ve been incrementally cleaning up the racks that service the lab network, and when I can get away with it, I’ve done the same for our production equipment.
I insist on color-coding patch cords by function; this saves a lot of time for anyone who needs to troubleshoot a communications fault or install new equipment. Although there’s a standards document that designates color codes in shared facilities (TIA/EIA-606-A), the scheme in its essence simply separates telephone from data from alarm systems. Over the years, I’ve developed my own method for identifying what’s what; here’s what I did for the new offices:
From our old location we brought a large number of gray Cat 5 cords that were ideal for connecting the ports leading to our VOIP phones to the voice switch, so that was a starting point. There were also a decent number of blue Cat 5e cords, which became the color for data drops to offices and cubicles.
Vital links, such as WAN-to-LAN or interswitch connections, are designated in red or orange. I use two colors for contrast, with red being used for the most critical connections. (I used to reserve red for crossover cables, but I haven’t had to use one of those in donkey’s years.) In the lab’s color scheme, yellow cords connect our workbenches to the lab’s switch pile, while green cords connect the switches to a back-end management network. On the production side, those colors are reserved for the voice switch, which came from the vendor with its own color coding.
In our server cabinets, things are a little more ad hoc, and depend largely on what’s available in our patch cord inventory. These connections break down into data and management; our KVMs use Cat 5 cords to connect to modules that attach to the video and USB (PS/2 on some of our older gear) ports of each server in the cabinet. As long as we use one color consistently for the Ethernet links, and another for the KVM links, it doesn’t really matter that much what they are; they don’t even have to be consistent between cabinets, at least for now.
In previous situations, I’ve used black, white, pink and purple patch cords for various functions; some of that was decorative, but I always had some method to my madness. It turns out that pink is the most difficult to find; the vendor I’ve been using most recently doesn’t carry them at all. One idea that I didn’t have to explore this time around is using the cable boot to provide a second layer of color differentiation. This can get pricey, but in a particularly intricate wiring scheme, it’s worthwhile to factor that option into the purchase.
Part of a well-organized wiring scheme is finding the proper lengths for patch cords; some vendors offer a wider range of off-the-shelf lengths than others, and a good vendor will post prices for and supply half-foot increments without too much fuss.