Fiber cut - response in seconds?
deepak at ai.net
Mon Jun 1 18:43:10 CDT 2009
I'm not sure why this sounds so surprising or impressive... given g$vt
Monitoring software using a pair of fibers in your bundle. OTDR or
similar digital diagnostics. You detect a loss, you figure out how many
feet away it is. You look at your map.
A simpler way to do it (if you don't mind burning lots of fiber pairs)
would be to loop up a pair of fibers (or add a reflectance source every
1000 ft or so -- spliced into the cable). You can figure out to within a
thousand feet once you know WHICH set of loops has died.
Given it almost always involved construction crews, you drive until you
see backhoes for your final approximation.
If I were the gov't I'd have originally opted for #2, and then moved to #1.
"Seconds" is just a function of how far away the responding agency's
personnel ( monitoring the loop ) were from the cut. Obviously we are
talking about a few miles tops.
Plenty of people used to have a single pair in each bundle for
"testing". Its relatively trivial to make that a test pair live. This is
all predicated on you actually keeping your toplogy up-to-date.
Charles Wyble wrote:
> Joel Jaeggli wrote:
>> It's pretty trivial if know where all the construction projects on your
>> path are...
> How so? Setup OTDR traces and watch them?
>> I've seen this happen on a university campus several times. no black
>> helicopters were involved.
> Care to expand on the methodology used? A campus network is a lot
> different then a major metro area.
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