[30285] in North American Network Operators' Group
Re: Sonet protection usage
daemon@ATHENA.MIT.EDU (William Allen Simpson)
Wed Jul 26 00:10:07 2000
Message-ID: <397E635C.89929766@greendragon.com>
Date: Wed, 26 Jul 2000 00:04:53 -0400
From: William Allen Simpson <wsimpson@greendragon.com>
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To: danny@tcb.net
Cc: Steve Feldman <feldman@twincreeks.net>, nanog@merit.edu
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Think about it -- are they really provisioning two circuits, leaving
one available as a backup? Of course not!
This may be a useful feature for voice circuits, where most of the
capacity sits idle most of the time. It's worse than useless for data.
APS was designed to protect against the failure of the electronics
for a single fiber in a cable. Often, a dozen other circuits are
"protected" by a single APS. It's a ripoff.
Of course, the usual failure mode is backhoe fade, not electronics.
In which case, that APS circuit was cut along with the rest.
For transoceanic links, diverse APS is even more unlikely, and unless
you are paying serious money, you won't be a priority over the other
hundred customers that are sharing that APS circuit.
Diverse links _are_ the only _real_ protection. You might even get
what you pay for.... And in the short term, you at least get twice
the bandwidth.
WSimpson@UMich.edu
Key fingerprint = 17 40 5E 67 15 6F 31 26 DD 0D B9 9B 6A 15 2C 32
