nanog mailing list archives
Re: DC fiber cut: field report
From: "Jay R. Ashworth" <jra () scfn thpl lib fl us>
Date: Sun, 20 Jul 1997 12:14:54 -0400
On Fri, Jul 18, 1997 at 06:44:21PM -0400, Robert E. Seastrom wrote:
Am I the only one who's a cables and switches weenie enough to know that the telco's _already do this_? Large numbers of local multi-pair
^^^^^^^^^^^^^^^^
trunking cables are pressurized with nitrogen, and they put pressure drop alarms on them, so they know if one takes a hit. pressurized nitrogen is usually done to keep moisture out, not so that they can monitor pressure loss. pressure loss in a fed, very long, pipe is an extremely local phenomenon anyway. i think there are spooks at some black agencies that monitor against tapping this way. but in practice, nitrogen pressurization is only done for copper.
Yes. I know. ;-) I'm told they really do pressure loss monitor the local stuff, though, even if more for dryness purposes than cable-break. Cheers, -- jra -- Jay R. Ashworth jra () baylink com Member of the Technical Staff Unsolicited Commercial Emailers Sued The Suncoast Freenet "People propose, science studies, technology Tampa Bay, Florida conforms." -- Dr. Don Norman +1 813 790 7592
Current thread:
- RE: DC fiber cut: field report, (continued)
- RE: DC fiber cut: field report Dan Dale (Jul 18)
- Re: DC fiber cut: field report Owen DeLong (Jul 18)
- Re: DC fiber cut: field report Dave O'Shea (Jul 18)
- Re: DC fiber cut: field report Owen DeLong (Jul 18)
- Re: DC fiber cut: field report Andrew Partan (Jul 18)
- Re: DC fiber cut: field report Hal Murray (Jul 22)
- Re: DC fiber cut: field report Adrian J Bool (Jul 18)
- Re: DC fiber cut: field report Stephen Sprunk (Jul 18)
- Message not available
- Re: DC fiber cut: field report Jay R. Ashworth (Jul 18)
- Re: DC fiber cut: field report Stephen Balbach (Jul 18)
- Message not available
- Message not available
- Re: DC fiber cut: field report Jay R. Ashworth (Jul 20)
- Re: DC fiber cut: field report Owen DeLong (Jul 18)
- RE: DC fiber cut: field report Dan Dale (Jul 18)
- Re: DC fiber cut: field report Sean M. Doran (Jul 23)