Cable Colors

Gadi Evron ge at
Tue Jun 17 01:32:15 UTC 2008

On Mon, 16 Jun 2008, Glenn Sieb wrote:
> 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.

Others responded with what colour goes for what. Me? I learned that these 
colour conventions change drastically from one place to another.

Other than which interface or network you may be using, there is the 
issues of "sensitive"/secret network and white/public network.

In one organization red was for the sensitive private network, and in 
another red meant "danger Will Robinson", public unsafe network. In yet 
another red was for grounded power.

Use what works for you.

Warning about colours with a funny anecdote:

In a more secure network I ran security for, networks were literally 
separated and colour coded cables were enforced.

One day a cable needed to be replaced but we ran out of the said colour. 
The engineer was so scared of what the then security director (before my 
time) would say that he didn't fix the network for .. some time...  until 
someone smacked him on the back of the head (the security 

To be fair the the engineer, he was really concerned about security. 
Security-minded networks have their own silly downsides. :)

Use what is comfortable and/or necessary, no more.


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