May 2000 - Test - lists.nanog.org

Re: Optical Crossconnects and IP
by Jerry Scharf 11 May '00

11 May '00

[...] > > I both fly (although tiny stuff only and otherwise only simulations ;-) > and do the networks stuff so here's a little comparison: > > Your airplane metapher almost works BUT if you talk about running even 300-400 > nodes with a link-state, you should compare it to flying an F18 formation of 30-40 > airplanes. A single one can turn well, yes, but try to get a coordinated, standard rate, announced > speed turn of 30 aircrafts and you start to understand the dynamics. There is a theory > that deals with that stuff (it's called in german "Schwarmtheorie", english equivalent to "swarm" > or "flock" probably) and it speaks about thing like center of a flock and it's mass ASIR but I never > saw it applied to networking, funny enough. So my point being, it's not like single-mass > Newtonian physics, > you basically get into the problem of Laplace grids (I think that's what the grids of masses > with springs inbetween were called ;-) and changing traffic characteristics are probably equivalent > to kinetic energy pumped into the system from its edges. > That's where your differential equation systems start to look > hard and pretty soon you're on the border of chaos theory. Somebody in Santa Fe should start > looking into that ;-) > [...] > > -- tony > Your point being that I have grossly underestimated the difficulty. A 20x20 grid transformed out of LaPlace space should generate thousands of significant partial differentail terms, then add the chaotic and discontinuous nature of the input. Gee, I wonder why the feeback loops are hard to stablize in networks. Add yet more by the fact that the faster you go, the higher the accelerations and the more unstable the system and the brute force stuff just keeps on looking better and better. jerry

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uunet europe outage
by JP Donnio 11 May '00

11 May '00

Hi, Although this is not a new problem (it started on 27 april), I wanted to let you know there are recurring transatlantic problems for UUnet networks in France, Uk, The Netherlands and Belgium (ASes 702, 3259, 1890, 2822, 1849). Symptom is that periodically transatlantic IP connectivity stops for periods between a few minutes to a few dozen minutes but BGP sessions are not interrupted. From UUnet France we have measured 13 outages of over 4 minutes since 1st May for a total of 168 minutes, including 6 outages today! More than just the problems that such connectivity failures cause, the fact that UUnet BGP sessions continue to announce unreachable networks prefixes during outages prevent all multihomed networks to efficiently handle those problems. As you might guess, UUnet has been providing no explanation at all except 1 fax sent to all its customers. The national NOCs seem totally unaware and unable to cope as the problem is transatlantic and handled in the US. There is no equivalent of www.noc.uu.net for european networks... What you should also know is that European UUnet networks are peering with very few networks other than their transit customers and that they rely on AS701. When transatlantic connectivity fails like this, most of the internet becomes unreachable. This message is not sent here in order to make UUnet react; we have already put the necessary pressure locally including public statements with no reaction at all. This is just to inform the community how european UUnet customers are treated. It is significant of the general low level of communication that European ISPs have with their customers, at least compared to the US. JP Donnio network consultant

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OT: How to value a domain (not for sale)
by Peter Galbavy 11 May '00

11 May '00

As part of a business planning exercise, I need to put a rough value on the intagible asset "knowledge.com". It is NOT currently for sale, please don't ask. I was hoping that some kind folks could point me in the direction of any evidence of domain name sales or similar that would at least help guestimate a nominal value. Anecdotal (sp?) eveidence of business.com and wallstreet.com on this list in the past helps, but if there is anything more concrete, I would greatly appreciate it. I will be happy to summarise to the list if anyone provides public information that I can republish. Regards, -- Peter Galbavy Knowledge Matters Ltd. http://www.knowledge.com/

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Re: OT: How to value a domain (not for sale)
by Shawn McMahon 11 May '00

11 May '00

On Thu, 11 May 2000, "Peter Galbavy" wrote: > > As part of a business planning exercise, I need to put a rough value on > the > intagible asset "knowledge.com". It is NOT currently for sale, please > don't > ask. The only number that can be projected in advance without being completely guessing is: $50 a year. Anything else is a guess until you actually hold the auction. Anybody that tells you they can estimate it is being disingenuous; anyone can estimate it, nobody's estimate matters a hill of beans.

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Level 3 is reporting fiber cuts in San Jose and San Francisco
by Ulf Zimmermann 11 May '00

11 May '00

No further details how many or where exactly. -- Regards, Ulf. --------------------------------------------------------------------- Ulf Zimmermann, 1525 Pacific Ave., Alameda, CA-94501, #: 510-769-2936 Alameda Networks, Inc. | http://www.Alameda.net | Fax#: 510-521-5073

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Important NANOG 19 Meeting Announcements
by Carol Wadsworth 11 May '00

11 May '00

Important NANOG 19 Meeting Announcements: HOTEL Hotel rooms in the NANOG room block at the Hyatt Regency Albuquerque have all been reserved. Unfortunately, the hotel cannot increase the block because they are at full capacity (sold out). The Hyatt is recommending the following two hotels: Doubletree ( $159 and up) 201 Marquette, NW Phone: 505-247-3344 La Posada ($79 and up) 125 Second Street Phone: 505-242-9090 REGISTRATION: The meeting will be limited to first 500 registrants because of space limitation at the hotel. There are currently 440 registrants to date. We will need to close registration early if the 500 limit is reached prior to the June 2 deadline. If so, walk-in attendees won't be permitted, as in the past, and a waiting list will need to be established. https://www.merit.edu/nanog/registration.form.html PAYMENT STATUS: If you already registered for the meeting, please check your payment status out on the attendee list on the web. Your registration fee must be received by June 2, after that date the registration fee increases $50. http://www.nanog.org/mtg-0006/Registration.List.html A list of preliminary agenda topics is now posted on the NANOG web page. Hope you can make it to Albuquerque for NANOG 19. Thanks. Carol Wadsworth Merit Network, Inc.

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Re: Optical Crossconnects and IP
by Vadim Antonov 11 May '00

11 May '00

I would like to inject some sanity into the traffic engineering discussion by reminding about some small fact of life: Nobody knows how to measure how what the demanded/available bandwidth ratio is when the circuit is overloaded. In a steady more, utilization is s 100%; packet loss is not an accurate gauge, by any means (it depends on delays, agressiveness os sources, queue manageent policies, timing of source starts, and phase of the moon). What it means that by and large traffic engineering is done by seat of the pants. An attempt to create a close control loop with that kind of source information is somewhat problematic. And so is "wavelength on demand". When circuits aren't overloaded, traffic engineering yields zero benefit. --vadim PS I just love engineers spending untold hours and companies spending billions on a technology of questionable worth and little theoretical foundations, instead of spending a small fraction of it on research first. PPS Pluris core technology allows to treat traffic as a liquid - unlike simple IP routing it works by splitting aggregated streams, which can be sent along different paths. It makes any VC-based traffic engineering and associated hardware overhead simply unnecessary. I'm more than a little disappointed by the fact that this is apparently lost in the mind of the company's current architects. (Admittedly, it still requires some work on algorithms, but at least routing of colored liquids is much easier computationally than routing of VCs).

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Re: Japan's NTT Com To Buy Verio
by Paul Vixie 11 May '00

11 May '00

> Spamwise? Verio has had an above-average response to spam coming from or through their network. I expect that this policy will continue to improve, and that an NTT buyout won't affect it at all. (Randy's PSG was one of the first BGP-level subscribers to the MAPS RBL.)

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Strange result while ping serial interface
by Yu Ning 10 May '00

10 May '00

Hi nanog, Strange thing happens everyday. When I were troubleshooting yestoday, I found a ping to my local serial interface (no matter it's 155M POS, or 2M Serial interface) takes nearly twice delay compared with a ping to the remote side of the serial interrface ! When I trace to my local serial interface, I got the first hop to the remote end, then second hop back to my local interface ! For example, 202.97.2.1 is local serial interface, while 2.2 is remote side. A trace on 2.1 to 2.1 first go to 2.2, then back to 2.1. And this situation can be verified on both side. Have you ever seen this situation ? Is it due to our misconfiguration? or it's sheerly a mis-display of result in Cisco box (can't believe it) The background is: we're using ISIS as IGP, and utilized level-1/2 link. thanks for any input. regards, Yu Ning ------------------------------------------- (Mr.) Yu(2) Ning(2) ChinaNet Backbone Operation Networking Dep.,Datacom Bureau China Telecom.,Beijing(100088),P.R.C +86-10-66418121/66418122/66418123(fax) -------------------------------------------

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回复: ??: Strange result while ping serial interface
by Yu Ning 10 May '00

10 May '00

Thank you very much for your information. I get that page, and know it's for debugging reason. regards, Yu Ning -----Original Message----- From: Blake Fithen <fithen(a)NetworksPlus.com> To: 'Yu Ning' <yuning(a)cndata.com>; Dumb Kid <dumbkid0(a)yahoo.com>; nanog-post <nanog(a)merit.edu> Date: Thursday, May 11, 2000 10:07 AM Subject: RE: ??: Strange result while ping serial interface >>From the Cisco "System Management" document: > >http://www.cisco.com/univercd/cc/td/doc/product/software/ssr90/tsc_r90/5401 9 >.htm > > >"Note If the IP version of the ping command is used on a directly connected >interface, the packet is sent out the interface and should be forwarded >back to the router from the far end. The time travelled reflects this round >trip >route. This feature can be useful for diagnosing serial line problems. By >placing the local or remote CSU/DSU into loopback mode and "pinging" >your own interface, you can isolate the problem to the router or leased >line." > >blake > > >> -----Original Message----- >> From: Yu Ning [SMTP:yuning@cndata.com] >> Sent: Wednesday, May 10, 2000 9:00 PM >> To: Dumb Kid; nanog-post >> Subject: ??: Strange result while ping serial interface >> >> >> >> Hi, >> >> But it's obviously inefficient. Is it due to some inability of >> PPP ? Or can you tell what reason makes the packets a round >> trip ? >> >> Since the router should have the information of its local interface, >> why should it always send packets out, the get it back ? >> >> regards, >> >> Yu Ning >> >> -----Original Message----- >> From: Dumb Kid <dumbkid0(a)yahoo.com> >> To: Yu Ning <yuning(a)cndata.com>; nanog-post <nanog(a)merit.edu> >> Date: Thursday, May 11, 2000 9:45 AM >> Subject: Re: Strange result while ping serial interface >> >> >> >Yeah , it's normal. The packet actually travels to the >> >other end of the router over the serial and back. >> >That's why the response time is doubled. >> > >> > >> > >> >--- Yu Ning <yuning(a)cndata.com> wrote: >> >> >> >> Hi nanog, >> >> >> >> Strange thing happens everyday. When I were >> >> troubleshooting yestoday, >> >> I found a ping to my local serial interface (no >> >> matter it's 155M POS, >> >> or 2M Serial interface) takes nearly twice delay >> >> compared with a ping >> >> to the remote side of the serial interrface ! When I >> >> trace to my local >> >> serial interface, I got the first hop to the remote >> >> end, then second >> >> hop back to my local interface ! >> >> >> >> For example, 202.97.2.1 is local serial interface, >> >> while 2.2 is remote >> >> side. A trace on 2.1 to 2.1 first go to 2.2, then >> >> back to 2.1. And this >> >> situation can be verified on both side. >> >> >> >> Have you ever seen this situation ? Is it due to our >> >> misconfiguration? >> >> or it's sheerly a mis-display of result in Cisco box >> >> (can't believe it) >> >> >> >> The background is: we're using ISIS as IGP, and >> >> utilized level-1/2 link. >> >> >> >> thanks for any input. >> >> >> >> regards, >> >> >> >> Yu Ning >> >> ------------------------------------------- >> >> (Mr.) Yu(2) Ning(2) >> >> ChinaNet Backbone Operation >> >> Networking Dep.,Datacom Bureau >> >> China Telecom.,Beijing(100088),P.R.C >> >> +86-10-66418121/66418122/66418123(fax) >> >> ------------------------------------------- >> >> >> >> >> >> >> > >> > >> >===== >> > >> >-- >> >D.U.M.B.K.I.D. >> > >> >__________________________________________________ >> >Do You Yahoo!? >> >Send instant messages & get email alerts with Yahoo! Messenger. >> >http://im.yahoo.com/ >> > >> >

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