Cable Colors

Derek J. Balling deballing at
Mon Jun 16 22:48:46 UTC 2008

On Jun 16, 2008, at 6:41 PM, Glenn Sieb wrote:
> Hmm. I've always done blue for "safe" or "internal" connections, red  
> for machines on the DMZ or outside.

I think this varies a lot based on the environment...

I've seen :

-	Red for external ("hot"), Blue for internal ("cold")

-	Red for external ("stop this"), green for internal ("go/trusted")

-	Red for internal ("stop this from leaving") and green for external  
("go go go to the outside world")

-	A combination of the either of the last two with "Yellow" for a  
cautionary DMZ area

And then there's the environment I'm in right now, where there are a  
LOT of different cable colors for different reasons.

The reality is, from my experience, to find a color combination that  
makes sense to you and is intuitive to you and the people who'll be  
working with the cables.

Amusing cautionary tale: confirm that you don't have any color-blind  
staff, and if you do, make sure they can differentiate all your cable  
colors before you set them in stone and deploy them.   :-)


-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 2478 bytes
Desc: not available
URL: <>

More information about the NANOG mailing list