[11133] in North American Network Operators' Group
Re: DC fiber cut: field report
daemon@ATHENA.MIT.EDU (Hal Murray)
Tue Jul 22 05:14:37 1997
To: Andrew Partan <asp@partan.com>
Cc: murray@pa.dec.com, nanog@merit.edu
In-Reply-To: Message of Fri, 18 Jul 1997 15:30:52 -0400 (EDT)
from Andrew Partan <asp@partan.com>
<199707181930.PAA27098@home.partan.com>
Date: Tue, 22 Jul 97 02:03:02 -0700
From: Hal Murray <murray@pa.dec.com>
> The story that I have heard is that some providers have 1 (one)
> protect circuit to cover many primary circuits... You loose too
> many primary and limit number of protect circuits can't get them
> all.
> --asp@partan.com (Andrew Partan)
I'm not a TELCO wizard.
The impression I get is that the protection circuit is intended to
cover failures that take out a single circuit. For example, if you
had 10 fibers in a system and a repeater or laser died, then only
one of your fibers stops working. Fixing that with a protection
circuit adds 1/10 to the system cost. (Maybe less if you have spare
fibers in the ground.) Fixing it with SONET ring technology roughly
doubles the system cost.
A protection circuit doesn't help if your problem is backhoes.
