As we left it struck me that this cut was not if, but when. And more cuts
like it. There was no protection for the cable, no markers of the cable location.
One of the interesting things about the startup of Wiltel was pulling fiber through decommisioned gas pipelines; not only do you get a 1/4" steel backhoe fade margin, but you get scary yellow signs that say "DANGER: HIGH PRESSURE NATURAL GAS LINE"; cut a piece of innerduct and your boss yells at you. Bust a gas pipeline and they can bury what's left of the offender in a thimble - if they can find it.
As we left it struck me that this cut was not if, but when. And more cuts
like it. There was no protection for the cable, no markers of the cable location.
One of the interesting things about the startup of Wiltel was pulling fiber through decommisioned gas pipelines; not only do you get a 1/4" steel backhoe fade margin, but you get scary yellow signs that say "DANGER: HIGH PRESSURE NATURAL GAS LINE"; cut a piece of innerduct and your boss yells at you. Bust a gas pipeline and they can bury what's left of the offender in a thimble - if they can find it.
Gee, makes a good case for putting innerduct inside conduit and putting gas through it just to discourage BIFF. :-) The thing that doesn't make sense to me in all of this is that SONET is supposed to be built as RINGS. With a Service side and a Protect side to each switch. BIFF should, in theory, only take out one or the other, but not both. WHY, with what we pay these carriers every month, do they not divergent-path route these critical wide-area links so that this isn't fatal?
Anyone from MFS/WilTel/WorldCom/UUNET/AlterNet/whoever-else-they-buy-but- still-don't-fix-what-they-have care to comment? Owen DeLong Exodus
The thing that doesn't make sense to me in all of this is that SONET is supposed to be built as RINGS. With a Service side and a Protect side to each switch.
The story that I have heard is that some providers have 1 (one) protect circuit to cover many primary circuits... You loose too many primary and limit number of protect circuits can't get them all. --asp@partan.com (Andrew Partan)
On Fri, 18 Jul 1997, Owen DeLong wrote:
The thing that doesn't make sense to me in all of this is that SONET is supposed to be built as RINGS. With a Service side and a Protect side to each switch. BIFF should, in theory, only take out one or the other, but not both. WHY, with what we pay these carriers every month, do they not divergent-path route these critical wide-area links so that this isn't fatal?
I suppose because you account for about 0.0001% of their total revenue. Hey, youre lucky for our accountabilty you could shove a few extra naughts in the middle ;-( At the end of the day, are you going to cancel all your circuits with them? I doubt it - I have been tempted with certian telcos but the cost and hassle, all *after* the downtime has occured ain't always worth it. I bet the telcos are betting on that. Regards & Good luck with your diveristy! aid
At 11:59 07-18-97 -0700, you wrote:
The thing that doesn't make sense to me in all of this is that SONET is supposed to be built as RINGS. With a Service side and a Protect side to each switch. BIFF should, in theory, only take out one or the other, but not both. WHY, with what we pay these carriers every month, do they not divergent-path route these critical wide-area links so that this isn't fatal?
The usual response is that carriers are over-provisioning lines (more than 50% of capacity used). Voice links usually get priority during rerouting; perhaps all the Tier-1 internet links are being provisioned in the "above 50%" section of the fiber, since Internet outages aren't as costly as voice outages. However, what if Backhoe Fade is far more common than advertised, and we only find out about cuts when BOTH sides of the rings are hit? Is there any practical way to measure/detect SONET failover from an endpoint? Stephen -- Unsolicited commercial/propaganda email subject to legal action. Under US Code Title 47, Sec.227(a)(2)(B), Sec.227(b)(1)(C), and Sec.227(b)(3)(C), a State may impose a fine of not less than $500 per message. Read the full text of Title 47 Sec 227 at http://www.law.cornell.edu/uscode/47/227.html
On Fri, Jul 18, 1997 at 11:59:11AM -0700, Owen DeLong wrote:
Gee, makes a good case for putting innerduct inside conduit and putting gas through it just to discourage BIFF. :-)
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. 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
On Fri, 18 Jul 1997, Jay R. Ashworth wrote:
On Fri, Jul 18, 1997 at 11:59:11AM -0700, Owen DeLong wrote:
Gee, makes a good case for putting innerduct inside conduit and putting gas through it just to discourage BIFF. :-)
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
The 144 fiber strand WorldCom cable between DC and NYC doesnt do this. It carries Sprint, Cable and Wireless and a few other telco's as well. --stb
participants (7)
-
Adrian J Bool -
Andrew Partan -
Dave O'Shea -
Jay R. Ashworth -
owen＠DeLong.SJ.CA.US -
Stephen Balbach -
Stephen Sprunk