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Re: MCI WorldCom fiber cut - [belated]
by David Lesher 25 Oct '99

25 Oct '99

Unnamed Administration sources reported that Daniel Senie said: > > When gas installers lay underground plastic gas lines (I have such > running to my backup generator) they lay a wire in the ground next to > the pipe. {} > The next thing done when an underground gas pipe is laid, is a mylar > film is buried, a foot or so above the pipe, which has all kinds of > warnings on it about the gas line below. The tape is mirror-reflective > mylar. A) I've never seen fiber without wire for the locaters to use later. B) Fiber duct is often punched through with a ram, not buried by cut & cover methods; it being far cheaper to ram. But b1) that means there is no way to leave "buried trouble below" tape and b2) the NEXT guy will likely be ramming as well so even if there was tape, no one would see it. Note the ram is a source of many problems. The protypical is the cas company uses one to install a new plastic line to a house, inadventently going clean through a 6" sewer line. Trees soon clog the sewer with roots, and a sewer company roto-rooters [tm] the line clear, flooding the sewer system and basement with gas. Kaboom. -- A host is a host from coast to coast.................wb8foz(a)nrk.com & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433

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Fwd: Other types of underground utilities
by wb8foz＠nrk.com 24 Oct '99

24 Oct '99

Mike Heller <mikeh(a)earthweb.com> writes: > I find it interesting that we don't hear about more accidental gas > explosions and water main breaks from backhoes. Are the blueprints and > posted warnings more detailed or is there more fiber than utility pipe in > the ground? {Tardy reply} Ha! I was in the pipeline business. It happens all the time. See <http://www.underspace.com/> About a year ago, a woman in a new tract house out by Dulles died after the basement filled with gas & it exploded. The line had been nicked -- suspected cause: the electric utility laying THEIR feed. Every few years, someone hits a LPG line and turns into marshmallow. A public housing building in Chicago was destroyed when a gas line was hit -- ?18 months? ago or so. -- A host is a host from coast to coast.................wb8foz(a)nrk.com & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433

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RE: Traffic engineering tools
by Bora Akyol 22 Oct '99

22 Oct '99

First of all, a multicommodity flow problem is not NP-complete provided that the individual flows are an order of magnitude or so smaller than the link capacities so that you can use a fluid approximation. Moreover, you can come up with a heuristic that works pretty well. I believe you must have heard of greedy algorithms. It is **so** easy to label a problem NP complete these days. Bora -----Original Message----- From: Andrew Bender [mailto:abender@tns-inc.com] Sent: Friday, October 22, 1999 2:01 PM To: nanog(a)merit.edu Subject: RE: Traffic engineering tools > Date: Thu, 21 Oct 1999 20:49:07 -0700 > From: Bora Akyol <akyol(a)pluris.com> > Subject: RE: Traffic engineering tools > > If you don't want a GUI and the fancy what if scenarios, it is not difficult > to write > a Perl/Script that does constraint-based routing or Multi-commodity flow > problems. > > I would guess 2-3 weeks if one is familiar with basic linear programming. > > Bora Release note: NPcomplete.pl may also require 2-3 weeks to converge when sub{optimum_backup_paths} is used. This may be due to a suspected "suboptimality" in PDL::Opt::Simplex... Application note: "basic" as the term is used in the context of the phrase "basic linear programming" seen in the marketing literature should be taken to mean "graph or subgraph of degree 1" Regards, Andrew Bender Total Network Solutions, Inc. P.S. Advance apologies for the (ostensibly excusable?) off topic cynicism...

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RE: Traffic engineering tools
by Andrew Bender 22 Oct '99

22 Oct '99

> Date: Thu, 21 Oct 1999 20:49:07 -0700 > From: Bora Akyol <akyol(a)pluris.com> > Subject: RE: Traffic engineering tools > > If you don't want a GUI and the fancy what if scenarios, it is not difficult > to write > a Perl/Script that does constraint-based routing or Multi-commodity flow > problems. > > I would guess 2-3 weeks if one is familiar with basic linear programming. > > Bora Release note: NPcomplete.pl may also require 2-3 weeks to converge when sub{optimum_backup_paths} is used. This may be due to a suspected "suboptimality" in PDL::Opt::Simplex... Application note: "basic" as the term is used in the context of the phrase "basic linear programming" seen in the marketing literature should be taken to mean "graph or subgraph of degree 1" Regards, Andrew Bender Total Network Solutions, Inc. P.S. Advance apologies for the (ostensibly excusable?) off topic cynicism...

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The Cidr Report
by Tony Bates 22 Oct '99

22 Oct '99

This is an auto-generated mail on Fri Oct 22 12:00:01 PDT 1999 It is not checked before it leaves my workstation. However, hopefully you will find this report interesting and will take the time to look through this to see if you can improve the amount of aggregation you perform. The report is split into sections: 0) General Status List the route table history for the last week, list any possibly bogus routes seen and give some status on ASes. 1) Gains by aggregating at the origin AS level This lists the "Top 30" players who if they decided to aggregate their announced classful prefixes at the origin AS level could make a significant difference in the reduction of the current size of the Internet routing table. This calculation does not take into account the inclusion of holes when forming an aggregate so it is possible even larger reduction should be possible. 2) Weekly Delta A summary of the last weeks changes in terms of withdrawn and added routes. Please note that this is only a snapshot but does give some indication of ASes participating in CIDR. Clearly, it is generally a good thing to see a large amont of withdrawls. 3) Interesting aggregates Interesting here means not an aggregate made as a set of classful routes. Thanks to xara.net for giving me access to their routing tables once a day. Please send any comments about this report directly to me. Check http://www.employees.org/~tbates/cidr-report.html for a daily update of this report. ------------------------------------------------------------------------------ CIDR REPORT for 22Oct99 0) General Status Table History ------------- Date Prefixes 151099 65450 161099 65076 171099 65195 181099 65279 191099 65291 201099 65598 211099 65550 221099 65598 Check http://www.employees.org/~tbates/cidr.plot.html for a plot of the table history. Possible Bogus Routes --------------------- *** Bogus 110.30.236.0/24 from AS577 AS Summary ---------- Number of ASes in routing system: 5854 Number of ASes announcing only one prefix: 3086 (1688 cidr, 1398 classful) Largest number of cidr routes: 583 announced by AS701 Largest number of classful routes: 945 announced by AS701 1) Gains by aggregating at the origin AS level --- 22Oct99 --- ASnum NetsNow NetsCIDR NetGain % Gain Description AS271 383 144 239 62.4% BCnet Backbone AS719 733 567 166 22.6% LANLINK autonomous system AS7046 397 260 137 34.5% UUNET-CUSTOMER AS9269 139 15 124 89.2% Hong Kong CTI AS2609 128 8 120 93.8% EUnet-TN AS1221 623 513 110 17.7% TELSTRA-AS AS6944 124 20 104 83.9% RapidSite, Inc. AS174 573 483 90 15.7% Performance Systems International AS7657 249 161 88 35.3% The Internet Group Limited AS4293 228 142 86 37.7% Internal ASN for C&W AS577 265 180 85 32.1% Bell Canada Backbone AS7496 113 36 77 68.1% Power Up AS7545 140 64 76 54.3% TPG Internet Pty Ltd AS3749 140 64 76 54.3% TECNET AS4200 184 110 74 40.2% AGIS (Apex Global Information Ser AS4740 340 288 52 15.3% Ozemail Pty Ltd (ASN-OZEMAIL) AS209 314 265 49 15.6% Qwest Communications AS684 92 46 46 50.0% Manitoba Regional Network Backbon AS701 945 900 45 4.8% Alternet AS816 224 181 43 19.2% UUNET Canada (ASN-UUNETCA-AS4) AS549 221 178 43 19.5% ONet Backbone AS2493 134 93 41 30.6% iSTAR Internet, Inc. AS9304 54 15 39 72.2% Hutchcity AS6528 45 7 38 84.4% WORLD-LYNX AS4755 97 63 34 35.1% Videsh Sanchar Nigam Ltd. India AS1 497 463 34 6.8% GTE Internetworking AS6172 146 113 33 22.6% HOME-NET-1 AS3737 99 66 33 33.3% PenTeleData Inc. (ASN-PTD) AS1785 236 204 32 13.6% NYSERNet Backbone AS9453 33 2 31 93.9% Soongsil University For the rest of the previous weeks gain information please see http://www.employees.org:80/~tbates/cidr-report.html 2) Weekly Delta Please see http://www.employees.org:80/~tbates/cidr-report.html for this part of the report 3) Interesting aggregates Please see http://www.employees.org:80/~tbates/cidr-report.html for this part of the report

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Re: Targeted LDP and Hierarchical LSPs in MPLS networks
by Vadim Antonov 22 Oct '99

22 Oct '99

Just for the record - i was against doing MPLS in Pluris boxes. There's a much better way to do traffic engineering using Pluris' load-distribution trick. I guess marketing won. --vadim > I would like to get a poll on how targeted LDP sessions (and hierarchical > tunnels) and MPLS data path tie together. > Bora Akyol, Pluris > http://www.pluris.com

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NANOG 17
by Pam Ciesla 22 Oct '99

22 Oct '99

If you paid for NANOG 17 but did not attend please contact me for a refund by Monday, November 1, 1999. There will be a $35 cancellation fee. If you need copies of receipts include fax number or mailing address. Sorry for the delay in this message. Pam Pam Ciesla Events Coordinator Merit Network,Inc. 734-936-0172 - phone 4251 Plymouth Road 734-647-3185 - fax Bldg.I, Suite C pam(a)merit.edu Ann Arbor, MI 48105

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RE: Traffic engineering tools
by Bora Akyol 22 Oct '99

22 Oct '99

If you don't want a GUI and the fancy what if scenarios, it is not difficult to write a Perl/Script that does constraint-based routing or Multi-commodity flow problems. I would guess 2-3 weeks if one is familiar with basic linear programming. Bora -----Original Message----- From: Robert Tsay [mailto:cctsay@globalcenter.net] Sent: Thursday, October 21, 1999 5:28 PM To: Bora Akyol; 'Sean Donelan'; nanog(a)merit.edu Subject: Re: Traffic engineering tools After the investigation, currently only WANDL in the market can do/support the MPLS+ATM or IP simulation. So the bad thing is the software is very expensive. It's the only software that can simulate Constraint-Based routing now. R. ----- Original Message ----- From: Bora Akyol <akyol(a)pluris.com> To: 'Sean Donelan' <sean(a)donelan.com>; <nanog(a)merit.edu> Sent: Thursday, October 21, 1999 2:25 PM Subject: RE: Traffic engineering tools > > I believe that WANDL has a tool that can be used for > static TE purposes, but you are on your own for traffic > models. > > Bora Akyol > Pluris, http://www.pluris.com > > -----Original Message----- > From: Sean Donelan [mailto:sean@donelan.com] > Sent: Wednesday, October 20, 1999 11:21 PM > To: nanog(a)merit.edu > Subject: Traffic engineering tools > > > > At NANOG the lack of traffic engineering tools came up. Has anyone > heard of any packages coming to market. Or looked if tools from > other industries could be used as a starting point. Anything from > the electric power transmission or road traffic world we could use? > Or do IP packets have such different properties (e.g. re-transmission, > independent next-hop behavior, etc), its not a good idea to even try. > >

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Re: Traffic engineering tools
by Sean Donelan 22 Oct '99

22 Oct '99

The votes are in, and the commercial winner for IP traffic engineering, planning, modeling, etc package is WAN DL <http://www.wandl.com/> The most frequent comment was "its expensive." Although WAN DL was the (only) commercial package mentioned, several people reported they are working with some homegrown tools, or SWAG. However no one was real happy with either the available commercial or homegrown tools they were using. Several vendor-types sent messages they are working on new tools for release "any day now." I was surprised I didn't hear about any projects from the academic world. The number of CS graduates continues to decline, have we dropped below critical mass?

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DNS for 16.172.in-addr.arpa
by grisha＠verio.net 21 Oct '99

21 Oct '99

We were having a small problem here and I traced it down to a reverse DNS lookup on a 172.16 address hanging. I noticed that a.root-servers.net reports that BLACKHOLE.ISI.EDU is authoritative for 16.172.in-addr.arpa. Is this the way it should be, or is the yet another network solutions mistake? Who should really handle DNS for rfc1918 addresses? Grisha

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