Cable Colors

Joe Greco jgreco at
Mon Jun 16 22:59:26 UTC 2008

> JoeSox wrote:
> > Hello Newbie here (hopefully I have the correct list),
> >
> > I was just wondering if anyone knows of a website with recommended
> > colors for cables for a new datacenter?
> > I have written some things down but I don't want to get stuck saying
> > 'darn, I wish I would have bought this color for this type, now I am
> > stuck'.
> > What standard color to use if voice and data on same interface etc. Thanks.
> >   
> Hmm. I've always done blue for "safe" or "internal" connections, red for 
> machines on the DMZ or outside.
> Perhaps Blue for internal data, Yellow for internal voice, Green for 
> data/voice?
> Don't know if there's a website on this, but you can definitely read 
> about it in Tom Limoncelli's The Practice of System and Network 
> Administration book.

What you do is largely going to be dependent on what your situation is.
"Data center" is exceedingly vague.

An ISP, with telco and data, customer colo and internal network circuits,
is going to have very different needs than some company that's running a
data processing network behind a firewall and gateway to the Internet
along with some minor telco circuits to serve the local user population.

Standardizing colors is very helpful, but keep a mind towards not getting
excessively complex unless the situation warrants it.  One of the most
important aspects to color coding is that you're trying to avoid connecting
things that might be bad.  In most environments, then, you might want to
have a "behind the firewall" color and a "DMZ" color.  However, consider
too that you might have a "management network" color, a "telco data circuit"
color, a "KVM-over-cat5-cable" color, a "Yost or Cisco standard Serial"
( color, etc. 

Those latter are exceedingly useful because you can sometimes toast
equipment if you're plugging in something with a very wrong signal type.

I happen to like orange for cross-connects, because it resembles multimode
fiber (which is what most of our xc's are).  Beyond that, mostly you can
develop your own thing.  We use green for serial console.  Yellow might be
KVM or might be telecom.  There are some standards docs that provide
guidance, but I'm not sure that it matters.

In the old days, we used to color crossover cables differently too.  Thank
heavens that all the old non-auto-MDI/MDIX stuff is slowly going away.

... JG
Joe Greco - Network Services - Milwaukee, WI -
"We call it the 'one bite at the apple' rule. Give me one chance [and] then I
won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN)
With 24 million small businesses in the US alone, that's way too many apples.

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