Cable Colors

I don't know of any hard standard in use anywhere. I've generally taken
to the following:

Green == low-bandwidth straigh-through
  Telephone, T1, Serial, etc.
Purple == Roll Cables (almost always serial, sometimes telecom)
  (8-1 7-2 6-3 5-4 4-5 3-6 2-7 1-8)
Orange(C) == EIA-568b cross-over cable (ethernet xover)
Orange(F) == Multimode Fiber
Yellow(F) == Singlemode Fiber
White == Clear (inside VPN concentrator network)
Black == Crypt (Outside VPN concentrator network)
Blue == Publicly accessible networks
Red == Backend (usually OOB management) networks
Pink == KVM (KVM switch <-> Dongle)

Occasionally I encounter needs for greater specificity, but, these
usually do most of what I need.

Oh. That was the other thing I was going to say. Reserving some colors
for "special purposes" is a good idea.

... JG