Diversity - was: Fiber cut in SF area

Tue Apr 14 23:06:14 UTC 2009

-----Original Message-----
From: Roy [mailto:r.engehausen at gmail.com] 
Sent: Tuesday, April 14, 2009 6:43 PM
To: Gino Villarini
Cc: nanog at nanog.org
Subject: Re: Fiber cut in SF area

Gino Villarini wrote:
> Here in my area most of business outfits that require maximum
> availability of Internet or WAN conenctions have implemented dual
> connections from dual providers, most with a fiber/copper main and a
> fixed wireless backup.  This trend goes from banks to Mcdonalds  
>
>
> Gino A. Villarini
> gav at aeronetpr.com
> Aeronet Wireless Broadband Corp.
> tel  787.273.4143   fax   787.273.4145
>
>   
>A large company in the affected area had a T3 supplied by AT&T and a
>wireless link to another ISP that was fed by two metro-ethernet links
by
>companies other than AT&T.

>All three uplinks were lost.  So much for having backups,

This just goes to emphasize that when creating a diversity or backup
scenario, you need to get full disclosure from Provider B that they do
not use Provider A's facilities, including shared sheath, duct, etc in
any way. Also, there is the need to avoid the same telco buildings,
regen huts, etc.  and in some cases, entire cities. Any telecom/datacom
manager who has done their homework should be able to map out their
paths back to critical diverse infrastructure.

-Keith