telnet vs ssh on Core equipment , looking for reasons why ?

Bill Woodcock woody at zocalo.net
Wed Aug 1 02:29:56 UTC 2001


    > > in pressurized conduit - I fully believe some paranoid TLA's use 400PSI
    > > and a pressure-drop alarm as a deterrent.  I keep hearing rumors that
    > > involve 400PSI nerve gas, and I'm not sure if anybody is THAT paranoid. ;)
    >
    > It does not take 400 PSI, it just takes a couple more than atmospheric,
    > and the really nasty sensors are not looking just for breaks, but for
    > any pressure differential, such as caused by bending, moving, etc...
    > buts thats mostly for fiber in 'secure' installations.

Yep.  I've installed one network that was run in pressurized conduit.  It
wasn't high-pressure, but the pressure sensors were connected to an
out-of-band dedicated network inside the conduit, and the pressure varied
randomly over time.  All the sensors had to read basically the same
pressure as was being applied at that time, to keep the alarm from going
off.  This was just one element in an overall atmosphere of utter
paranoia, so it didn't seem all that crazy at the time, about ten years
ago.  I thought it would yield lots of false-positives, but surprisingly,
it didn't, and it was actually pretty good at pinpointing the location of
any breaks or blockages, relative to the sensors.  Ridiculously expensive.

                                -Bill





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