Re: FYI ONLY >> Non-Operational (at least directly)
It does not ease the situation WHEN your bits transit one provider's backbone (whom you chose to assure redundancy) does ultimately receive transit (at times such transit is not for long distances..) from a yet another whose infrastructure is now effected. I am not suggesting however, that is the case here.. AT&T is investigating. :)
Yeah, that's one reason why I stopped including the name of the carrier in most fiber cuts. It was getting too hard to tell who was who with all the swapping, leasing, sub-leasing, etc. Cable&Wireless is paying Level 3 $670 million for pieces of its fiber. GTE/BBN paid Qwest a ton for pieces of its fiber. AT&T, Sprint, MCI/Worldcom fiber overlaps so much its hard to tell them apart in some places. Qwest and IXC keep digging up other people's fiber, which would indicate their new fiber is being placed very close to other fiber. The non-facilities based carriers sometimes do better if they can guess which carriers have non-overlapping facilities, and buy from multiple physical facilities. But its not uncommon to see a dozen large ISPs have problems when someone trashes an interesting SONET ring somewhere, like Herndon/Mclean this morning. All the good right-of-ways are already taken. Heck, last year I was on some beautiful Caribbean islands with populations less than 100 people. We found both a backhoe and a cut telephone cable on them. In ten years (I ordered my first circuit in 1989), I've never gotten a good, coherent answer why any of my diversely, redundent circuits were both out-of-service at the same time due to the same event. Lots of credits, lots of apologies, but never a straight answer why something that should never happen, modulo the end of the world, happened. Good luck on AT&T's investigation.... -- Sean Donelan, Data Research Associates, Inc, St. Louis, MO Affiliation given for identification not representation
At 04:40 PM 4/13/99 -0500, Sean Donelan wrote: [details about fiber mangling cut (no pun intended :-) ]
In ten years (I ordered my first circuit in 1989), I've never gotten a good, coherent answer why any of my diversely, redundent circuits were both out-of-service at the same time due to the same event. Lots of credits, lots of apologies, but never a straight answer why something that should never happen, modulo the end of the world, happened.
Sometime in 1991 or so, when we were moving the SURAnet backbone from university campuses (campii?) to collocation space in MCI POPs throughout the southeast, I was talking to one of the MCI techs about the physically diverse T1s that MCI was contracted to deliver. He said if the same person engineered the routing for the circuits at the same time (which would only be done if it was specified on each order), then we might get lucky. Even if diversity is engineered in at first, shuffling circuits on cross connects and such would decrease the likelihood over time (an amazingly short amount of time) - and he also indicated that after a while, it was unlikely that anyone would even be able to determine on demand the actual path that any given circuit takes... :-/ I certainly hope that the systems for tracking this have improved, and also that they keep better track of DS3s and SONET better than they do DS1s.... but I'm skeptical. have fun out there, dave (now celebrating my 8th year of retirement from running networks :-)
Sean Donelan, Data Research Associates, Inc, St. Louis, MO Affiliation given for identification not representation
At 07:35 PM 4/13/99 -0400, David O'Leary wrote:
Sometime in 1991 or so, when we were moving the SURAnet backbone from university campuses (campii?) to collocation space in MCI POPs throughout the southeast, I was talking to one of the MCI techs about the physically diverse T1s that MCI was contracted to deliver. He said if the same person engineered the routing for the circuits at the same time (which would only be done if it was specified on each order), then we might get lucky. Even if diversity is engineered in at first, shuffling circuits on cross connects and such would decrease the likelihood over time (an amazingly short amount of time) - and he also indicated that after a while, it was unlikely that anyone would even be able to determine on demand the actual path that any given circuit takes... :-/
Naturally - they make a lot more money lying to you and then paying the penalty when they get caught. Like 100% SLAs - a provider who offers a 100% SLA *knows* they can't actually meet their guarantee, so they budget in $X for payment of the penalties. And sometimes they even make the process ridiculous to get your refund. Of course, we don't know any providers that would do something like that, do we? :)
I certainly hope that the systems for tracking this have improved, and also that they keep better track of DS3s and SONET better than they do DS1s.... but I'm skeptical.
So am I. :(( I know *exactly* which cables my E1s/T1s/DS3s/etc. are using - but I ain't got nearly as many as an MCI or a UUNET. I hear it's easier to do if you don't have a bazillion of them. ;) (OTOH, perhaps one should not use a provider that is so big the provider's engineering staff cannot even manage their own network.)
dave (now celebrating my 8th year of retirement from running networks :-)
Congrats. :-) TTFN, patrick I Am Not An Isp - www.ianai.net ISPF, The Forum for ISPs by ISPs, <http://www.ispf.com> "Think of it as evolution in action." - Niven & Pournelle (No, I still don't have enable.)
participants (3)
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David O'Leary -
I Am Not An Isp -
Sean Donelan