This all implies that the majority of fiber is in "tunnels" that can
be monitored. In my experience, almost none of it is in tunnels.
In NYC, it's usually buried in conduits directly under the street,
with no access, except through the man holes which are located about
every 500 feet.
In LA, a large amount of the fiber is direct bored under the streets,
with access from hand holes and splice boxes located in the grassy
areas between the street and the side walks.
Along train tracks, the fiber is buried in conduits which are direct
buried in the direct along side the train tracks, with hand holes
every 1000 feet or so.
In any of these scenarios, especially in the third, where the fiber
might run through a rural area with no road access and no cellphone
coverage. Simply walk through the woods to the train tracks, put open
a hand hole and snip, snip, snip, fiber cut.
Shane Ronan
On Apr 13, 2009, at 5:54 PM, Peter Beckman wrote:
On Mon, 13 Apr 2009, chris.ra...@nokia.com wrote:
I get the feeling you haven't deployed or operated large networks.
Nope.
You never did say what the multiplier was. How many miles or
detection
nodes there were. Think millions. The number that popped into my
head
when thinking of active detection measures for the physical network
is
$billions.
It depends on where you want to deploy it and how many miles you
want to
protect. I was thinking along the lines of $1.5 million for 1000
miles of
tunnel, equipment only. It assumes existing maintenance crews would
replace sensors that break or go offline, and that those expenses
already
exist.
All for a couple of minutes advanced notice of an outage? Would it
reduce the risk? No. Would it reduce the MTBF or MTTR? No. Of all
outages, how often does this scenario (or one that would trigger your
alarm) occur? I'm sure it's down on the list.
What if you had 5 minutes of advanced notice that something was
happening
in or near one of your Tunnels that served hundreds of thousands of
people
and businesses and critical infrastructure? Could you get someone
on site
to stop it? Maybe. Is it worth it? Maybe.
Given my inexperience with large networks, maybe fiber cuts and
outages
due to vandals, backhoes and other physical disruptions are just
what we
hear about in the news, and that it isn't worth the expense to
monitor for
those outages. If so, my idea seems kind of silly.
SLA's account for force de majure (including sabotage), so I really
doubt
there will be any credits. In fact, there will likely be an uptick
on
spending as those who really need nines build multi-provider multi-
path
diversity. Here come the microwave towers!
*laugh* Thank goodness for standardized GIS data. :-)
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Peter Beckman
Internet Guy
beck...@angryox.com http://www.angryox.com/
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