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Paging a RIM/Blackberry email staffer
by Jay R. Ashworth 19 Sep '08

19 Sep '08

Since postmaster@ is bouncing... (If you are not a RIM employee, you can stop reading now) Due to yahoo's DNS servers deciding to say, this morning, that my MX records point to email.vicimarketing.com.115, in that popular new ".115" gTLD... I moved the zone service inhouse. In the process, the email gateway recursors at Blackberry appear to have negative cached that my domain doesn't exist, and carbon copies to *all* of my various BIS BBs are bouncing "55 5.1.8 domain of sender address "jra(a)vicimarketing.com" does not exist". Anyone listening who can restart those recursive servers? Cheers, -- jra -- Jay R. Ashworth Baylink jra(a)baylink.com Designer The Things I Think RFC 2100 Ashworth & Associates http://baylink.pitas.com '87 e24 St Petersburg FL USA http://photo.imageinc.us +1 727 647 1274 Those who cast the vote decide nothing. Those who count the vote decide everything. -- (Josef Stalin)

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Level3 must have changed a lot on East Coast...any info?
by Patrick Giagnocavo 19 Sep '08

19 Sep '08

Does anyone have more info as to what Level3 changed last night during their maintenace window? Also I am going through either WashDC or Atlanta it seems, on most traceroutes. Here is a weird traceroute from this morning (note the first 4 traces): traceroute cwlabs.com (used as an example) traceroute to cwlabs.com (208.113.235.175), 30 hops max, 40 byte packets 1 ae-2.ebr3.Atlanta2.Level3.net (4.69.132.85) 142.747 ms 105.051 ms 106.480 ms 2 ae-2.ebr3.Atlanta2.Level3.net (4.69.132.85) 54.189 ms 52.121 ms 55.308 ms 3 ae-2.ebr3.Atlanta2.Level3.net (4.69.132.85) 52.709 ms 52.413 ms 53.878 ms 4 ae-2.ebr3.Atlanta2.Level3.net (4.69.132.85) 54.447 ms 55.481 ms 50.730 ms 5 ae-2.ebr3.Atlanta2.Level3.net (4.69.132.85) 55.489 ms 50.655 ms 54.116 ms 6 ae-7.ebr3.Dallas1.Level3.net (4.69.134.21) 75.441 ms 73.117 ms 69.460 ms 7 ae-3.ebr2.LosAngeles1.Level3.net (4.69.132.77) 99.071 ms 102.945 ms 109.537 ms 8 ae-82-82.csw3.LosAngeles1.Level3.net (4.69.137.26) 109.883 ms 106.218 ms 108.255 ms 9 ae-31-89.car1.LosAngeles1.Level3.net (4.68.20.131) 98.933 ms 100.706 ms 97.177 ms 10 INTERNAP-NE.car1.LosAngeles1.Level3.net (4.71.140.54) 97.548 ms 98.300 ms 97.674 ms 11 border20.po2-20g-bbnet2.lax.pnap.net (216.52.255.101) 102.012 ms 101.854 ms 98.889 ms 12 newdream-8.border20.lax.pnap.net (216.52.220.146) 97.053 ms 98.325 ms 97.547 ms 13 ip-66-33-201-66.dreamhost.com (66.33.201.66) 98.530 ms 101.100 ms 98.141 ms 14 basic-dap.marvin.dreamhost.com (208.113.235.175) 97.895 ms 97.204 ms 97.296 ms --Patrick

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Level(3) Issues
by James Baldwin 19 Sep '08

19 Sep '08

Is anyone else experiencing increased latency or packet loss through the Level3/Broadwing network? I have seen sporadic packet loss to several locations nationally over the last several hours.

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Sprint/Cogent Peering Issue?
by Craig Holland 19 Sep '08

19 Sep '08

Hi, We are seeing traffic getting dropped between our Cogent and Sprint connect DC's. One of them is getting shutdown, so we just have a Cogent link there :| Anyone seeing anything similar? From: 91.102.40.18 traceroute to ops1.scc.rnmd.net (208.91.188.136), 30 hops max, 38 byte packets 1 v1-core-sw1 (91.102.40.5) 0.471 ms 0.422 ms 0.431 ms 2 ge-0-1-0-pat2 (91.102.40.146) 0.376 ms 0.354 ms 0.335 ms 3 fe-1-3-1-501-pat1 (91.102.40.208) 0.376 ms 0.344 ms 0.407 ms 4 vl324.mpd01.lon01.atlas.cogentco.com (149.6.147.217) 0.745 ms 0.744 ms 0.740 ms 5 te3-1.mpd02.lon01.atlas.cogentco.com (130.117.2.26) 0.717 ms 39.037 ms te1-8.ccr01.lon01.atlas.cogentco.com (130.117.3.226) 0.565 ms 6 gi6-0-0.core01.lon01.atlas.cogentco.com (130.117.1.73) 0.592 ms 0.450 ms 0.483 ms 7 213.206.131.29 (213.206.131.29) 0.581 ms 0.503 ms 0.483 ms 8 sl-bb21-lon-3-0.sprintlink.net (213.206.129.152) 1.078 ms 0.905 ms 0.934 ms 9 * >From 208.91.188.138 traceroute to ops2.lnc.rnmd.net (91.102.40.18), 30 hops max, 38 byte packets 1 v1-core-sw1 (208.91.188.130) 0.600 ms 0.456 ms 2.105 ms 2 f0-0-4-0-pat2 (207.0.21.114) 0.416 ms 0.466 ms 0.486 ms 3 sl-st1-sc-2-6.sprintlink.net (144.228.111.25) 0.455 ms 0.224 ms 0.236 ms 4 sl-crs2-sj-0-1-0-3.sprintlink.net (144.232.20.196) 1.482 ms 1.477 ms 1.232 ms 5 sl-st20-sj-12-0-0.sprintlink.net (144.232.20.63) 2.482 ms 2.472 ms 2.485 ms 6 po5-3.core01.sjc03.atlas.cogentco.com (154.54.13.49) 2.732 ms 2.472 ms 2.485 ms 7 te3-1.mpd01.sjc03.atlas.cogentco.com (154.54.6.85) 2.705 ms 2.723 ms 2.735 ms 8 vl3493.ccr02.sjc01.atlas.cogentco.com (154.54.6.109) 3.231 ms vl3492.mpd01.sjc01.atlas.cogentco.com (154.54.6.105) 3.227 ms vl3491.ccr02.sjc01.atlas.cogentco.com (154.54.6.101) 2.726 ms 9 te9-3.mpd01.sfo01.atlas.cogentco.com (154.54.2.53) 3.968 ms 3.722 ms te8-3.ccr02.sfo01.atlas.cogentco.com (154.54.2.137) 3.988 ms 10 te9-2.ccr02.mci01.atlas.cogentco.com (154.54.24.118) 50.943 ms te7-4.mpd01.mci01.atlas.cogentco.com (154.54.24.106) 50.944 ms 50.720 ms 11 te9-3.ccr02.ord01.atlas.cogentco.com (154.54.25.78) 50.669 ms 63.423 ms te9-3.mpd01.ord01.atlas.cogentco.com (154.54.25.82) 51.206 ms 12 te2-1.ccr02.bos01.atlas.cogentco.com (154.54.7.170) 78.172 ms te3-3.mpd01.bos01.atlas.cogentco.com (154.54.7.82) 100.666 ms te2-1.ccr02.bos01.atlas.cogentco.com (154.54.7.170) 78.176 ms 13 * * * Thanks, craig ________________________ Craig Holland Rhythm NewMedia Sr. Director Operations & Integration YIM: cholland

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BGP Update Report
by cidr-report＠potaroo.net 19 Sep '08

19 Sep '08

BGP Update Report Interval: 18-Aug-08 -to- 18-Sep-08 (32 days) Observation Point: BGP Peering with AS2.0 TOP 20 Unstable Origin AS Rank ASN Upds % Upds/Pfx AS-Name 1 - AS9583 301731 3.8% 226.5 -- SIFY-AS-IN Sify Limited 2 - AS1803 126042 1.6% 94.9 -- ICMNET-5 - Sprint 3 - AS4538 107539 1.3% 21.4 -- ERX-CERNET-BKB China Education and Research Network Center 4 - AS5691 77600 1.0% 5969.2 -- MITRE-AS-5 - The MITRE Corporation 5 - AS8151 76788 1.0% 31.8 -- Uninet S.A. de C.V. 6 - AS6389 67460 0.8% 15.5 -- BELLSOUTH-NET-BLK - BellSouth.net Inc. 7 - AS9051 65154 0.8% 407.2 -- IDM Autonomous System 8 - AS209 51813 0.7% 10.8 -- ASN-QWEST - Qwest 9 - AS14593 50458 0.6% 50458.0 -- BRAND-INSTITUTE - Brand Instiute, Inc. 10 - AS10396 46699 0.6% 667.1 -- COQUI-NET - DATACOM CARIBE, INC. 11 - AS17488 44961 0.6% 30.8 -- HATHWAY-NET-AP Hathway IP Over Cable Internet 12 - AS4184 43385 0.5% 21692.5 -- STORTEK-WHQ - Storage Technology Corporation 13 - AS8866 39604 0.5% 123.0 -- BTC-AS Bulgarian Telecommunication Company Plc. 14 - AS20115 38076 0.5% 21.4 -- CHARTER-NET-HKY-NC - Charter Communications 15 - AS18231 36058 0.5% 146.0 -- EXATT-AS-AP IOL NETCOM LTD 16 - AS7018 35690 0.5% 24.2 -- ATT-INTERNET4 - AT&T WorldNet Services 17 - AS6663 35173 0.4% 286.0 -- EUROWEBRO Euroweb Romania SA 18 - AS9198 34983 0.4% 152.1 -- KAZTELECOM-AS Kazakhtelecom Corporate Sales Administration 19 - AS4755 33910 0.4% 19.5 -- TATACOMM-AS TATA Communications formerly VSNL is Leading ISP 20 - AS6458 31107 0.4% 70.2 -- Telgua TOP 20 Unstable Origin AS (Updates per announced prefix) Rank ASN Upds % Upds/Pfx AS-Name 1 - AS14593 50458 0.6% 50458.0 -- BRAND-INSTITUTE - Brand Instiute, Inc. 2 - AS4184 43385 0.5% 21692.5 -- STORTEK-WHQ - Storage Technology Corporation 3 - AS8266 9569 0.1% 9569.0 -- NEXUSTEL Nexus Telecommunications 4 - AS29910 8235 0.1% 8235.0 -- IACP - INTL. ASSN OF CHIEF OF POLICEI 5 - AS5691 77600 1.0% 5969.2 -- MITRE-AS-5 - The MITRE Corporation 6 - AS38180 5727 0.1% 5727.0 -- ETPI-IDS-JOLLIBEE-AS-AP 6/Fth floor JOLLIBEE PLAZA, Emerald Ave. Ortigas Center Pasig City. 7 - AS43299 4606 0.1% 4606.0 -- TELECONTACT-AS Telecontact Ltd. 8 - AS4557 7873 0.1% 3936.5 -- EP0-BLK-ASNBLOCK-7 - EP.NET, LLC. 9 - AS23082 18900 0.2% 3780.0 -- MPHI - Michigan Public Health Institute 10 - AS11971 21651 0.3% 3093.0 -- PFIZERNET-GROTON - PFIZER INC. 11 - AS30969 23119 0.3% 2311.9 -- TAN-NET TransAfrica Networks 12 - AS23917 2160 0.0% 2160.0 -- BRIBIE-NET-AS-AP Bribie Island Net Multihomed, Brisbane 13 - AS24491 1774 0.0% 1774.0 -- WORLDWEB-THAILAND-AS-AP Internet Service Provider Thailand 14 - AS44194 1590 0.0% 1590.0 -- FREIFUNK-BERLIN-AS Freifunk Berlin 15 - AS32011 1577 0.0% 1577.0 -- JOHO-NYC - Joho Capital, LLC 16 - AS9747 12268 0.1% 1533.5 -- EZINTERNET-AS-AP EZInternet Pty Ltd 17 - AS25321 1249 0.0% 1249.0 -- G4S-NET GROUP 4 SECURITAS Prague 18 - AS26276 5529 0.1% 1105.8 -- TIMKEN-USA - The Timken Company 19 - AS39843 2156 0.0% 1078.0 -- RATECOM-AS Joint Stock Company "Ratecom" 20 - AS3944 4275 0.1% 1068.8 -- PARTAN-LAB - Partan & Partan TOP 20 Unstable Prefixes Rank Prefix Upds % Origin AS -- AS Name 1 - 192.12.120.0/24 77527 0.9% AS5691 -- MITRE-AS-5 - The MITRE Corporation 2 - 221.134.222.0/24 59162 0.7% AS9583 -- SIFY-AS-IN Sify Limited 3 - 194.126.143.0/24 57735 0.7% AS9051 -- IDM Autonomous System 4 - 210.214.151.0/24 55122 0.6% AS9583 -- SIFY-AS-IN Sify Limited 5 - 12.8.7.0/24 50458 0.6% AS14593 -- BRAND-INSTITUTE - Brand Instiute, Inc. 6 - 210.210.112.0/24 44322 0.5% AS9583 -- SIFY-AS-IN Sify Limited 7 - 221.135.80.0/24 44047 0.5% AS9583 -- SIFY-AS-IN Sify Limited 8 - 221.135.251.0/24 42813 0.5% AS9583 -- SIFY-AS-IN Sify Limited 9 - 83.228.71.0/24 30651 0.4% AS8866 -- BTC-AS Bulgarian Telecommunication Company Plc. 10 - 221.128.192.0/18 27373 0.3% AS18231 -- EXATT-AS-AP IOL NETCOM LTD 11 - 72.50.96.0/20 24360 0.3% AS10396 -- COQUI-NET - DATACOM CARIBE, INC. 12 - 199.117.144.0/22 21694 0.2% AS4184 -- STORTEK-WHQ - Storage Technology Corporation 13 - 129.80.0.0/16 21691 0.2% AS4184 -- STORTEK-WHQ - Storage Technology Corporation 14 - 12.18.36.0/24 21381 0.2% AS11971 -- PFIZERNET-GROTON - PFIZER INC. 15 - 196.42.0.0/20 21180 0.2% AS10396 -- COQUI-NET - DATACOM CARIBE, INC. 16 - 89.38.98.0/23 18104 0.2% AS6663 -- EUROWEBRO Euroweb Romania SA 17 - 86.105.182.0/24 13985 0.2% AS6663 -- EUROWEBRO Euroweb Romania SA 18 - 195.251.5.0/24 12799 0.1% AS5408 -- GR-NET Greek Research & Technology Network, http://www.grnet.gr 19 - 89.4.131.0/24 12704 0.1% AS24731 -- ASN-NESMA National Engineering Services and Marketing Company Ltd. (NESMA) 20 - 205.162.132.0/23 12495 0.1% AS23541 -- Scarlet B.V. Details at http://bgpupdates.potaroo.net ------------------------------------ Copies of this report are mailed to: nanog(a)merit.edu eof-list(a)ripe.net apops(a)apops.net routing-wg(a)ripe.net afnog(a)afnog.org

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The Cidr Report
by cidr-report＠potaroo.net 19 Sep '08

19 Sep '08

This report has been generated at Fri Sep 19 21:18:31 2008 AEST. The report analyses the BGP Routing Table of AS2.0 router and generates a report on aggregation potential within the table. Check http://www.cidr-report.org for a current version of this report. Recent Table History Date Prefixes CIDR Agg 12-09-08 279371 169113 13-09-08 281264 169195 14-09-08 280983 169796 15-09-08 280912 169979 16-09-08 280891 170665 17-09-08 281142 171487 18-09-08 281677 171559 19-09-08 281956 171946 AS Summary 29399 Number of ASes in routing system 12454 Number of ASes announcing only one prefix 5025 Largest number of prefixes announced by an AS AS4538 : ERX-CERNET-BKB China Education and Research Network Center 88271360 Largest address span announced by an AS (/32s) AS721 : DISA-ASNBLK - DoD Network Information Center Aggregation Summary The algorithm used in this report proposes aggregation only when there is a precise match using the AS path, so as to preserve traffic transit policies. Aggregation is also proposed across non-advertised address space ('holes'). --- 19Sep08 --- ASnum NetsNow NetsAggr NetGain % Gain Description Table 281831 171930 109901 39.0% All ASes AS4538 5025 886 4139 82.4% ERX-CERNET-BKB China Education and Research Network Center AS6389 4295 351 3944 91.8% BELLSOUTH-NET-BLK - BellSouth.net Inc. AS209 2946 1334 1612 54.7% ASN-QWEST - Qwest AS4755 1728 303 1425 82.5% TATACOMM-AS TATA Communications formerly VSNL is Leading ISP AS6298 1981 756 1225 61.8% COX-PHX - Cox Communications Inc. AS8151 1736 584 1152 66.4% Uninet S.A. de C.V. AS17488 1384 286 1098 79.3% HATHWAY-NET-AP Hathway IP Over Cable Internet AS4323 1513 480 1033 68.3% TWTC - tw telecom holdings, inc. AS1785 1656 655 1001 60.4% AS-PAETEC-NET - PaeTec Communications, Inc. AS22773 979 65 914 93.4% CCINET-2 - Cox Communications Inc. AS11492 1217 411 806 66.2% CABLEONE - CABLE ONE AS18566 1049 276 773 73.7% COVAD - Covad Communications Co. AS19262 953 201 752 78.9% VZGNI-TRANSIT - Verizon Internet Services Inc. AS2386 1552 906 646 41.6% INS-AS - AT&T Data Communications Services AS9498 678 70 608 89.7% BBIL-AP BHARTI Airtel Ltd. AS6478 1169 587 582 49.8% ATT-INTERNET3 - AT&T WorldNet Services AS18101 754 192 562 74.5% RIL-IDC Reliance Infocom Ltd Internet Data Centre, AS3356 984 463 521 52.9% LEVEL3 Level 3 Communications AS4766 902 408 494 54.8% KIXS-AS-KR Korea Telecom AS4808 629 155 474 75.4% CHINA169-BJ CNCGROUP IP network China169 Beijing Province Network AS17676 524 63 461 88.0% GIGAINFRA BB TECHNOLOGY Corp. AS855 595 143 452 76.0% CANET-ASN-4 - Bell Aliant AS4134 842 390 452 53.7% CHINANET-BACKBONE No.31,Jin-rong Street AS7545 584 140 444 76.0% TPG-INTERNET-AP TPG Internet Pty Ltd AS22047 564 127 437 77.5% VTR BANDA ANCHA S.A. AS9443 522 86 436 83.5% INTERNETPRIMUS-AS-AP Primus Telecommunications AS7029 527 93 434 82.4% WINDSTREAM - Windstream Communications Inc AS24560 584 155 429 73.5% AIRTELBROADBAND-AS-AP Bharti Airtel Ltd., Telemedia Services AS7018 1418 1000 418 29.5% ATT-INTERNET4 - AT&T WorldNet Services AS4668 683 274 409 59.9% LGNET-AS-KR LG CNS Total 39973 11840 28133 70.4% Top 30 total Possible Bogus Routes 24.75.116.0/22 AS10796 SCRR-10796 - Road Runner HoldCo LLC 24.75.160.0/19 AS7843 ADELPHIA-AS - Road Runner HoldCo LLC 24.142.40.0/21 AS7018 ATT-INTERNET4 - AT&T WorldNet Services 24.142.160.0/19 AS7018 ATT-INTERNET4 - AT&T WorldNet Services 24.245.128.0/17 AS11492 CABLEONE - CABLE ONE 24.246.0.0/17 AS7018 ATT-INTERNET4 - AT&T WorldNet Services 24.246.128.0/18 AS7018 ATT-INTERNET4 - AT&T WorldNet Services 62.61.220.0/24 AS24974 TACHYON-EU Tachyon Europe BV - Wireless Broadband via Satellite 63.140.213.0/24 AS22555 UTC - Universal Talkware Corporation 63.143.71.0/24 AS701 UUNET - MCI Communications Services, Inc. d/b/a Verizon Business 63.143.115.0/24 AS701 UUNET - MCI Communications Services, Inc. d/b/a Verizon Business 63.143.251.0/24 AS22555 UTC - Universal Talkware Corporation 63.248.0.0/16 AS3356 LEVEL3 Level 3 Communications 64.7.112.0/21 AS6453 GLOBEINTERNET TATA Communications 64.7.120.0/21 AS6453 GLOBEINTERNET TATA Communications 64.64.159.0/24 AS32004 BIG-ASN - Business Information Group, Inc. 64.79.88.0/24 AS26096 LODDEN - Lodden Services 64.79.89.0/24 AS26096 LODDEN - Lodden Services 64.188.0.0/16 AS3356 LEVEL3 Level 3 Communications 66.11.32.0/20 AS6261 VISINET - Visionary Systems, Inc. 66.11.40.0/21 AS6261 VISINET - Visionary Systems, Inc. 66.54.91.0/24 AS30506 BLACKSUN-1 - Blacksun Technologies LLC 66.55.160.0/19 AS29994 66.180.239.0/24 AS35888 VIGNETTE - VIGNETTE CORPORATION 66.199.32.0/20 AS10397 WISP-AS - Wispnet, LLC 66.206.32.0/24 AS17787 PSEB-AS-PK Pakistan Software Export Board 66.206.33.0/24 AS17787 PSEB-AS-PK Pakistan Software Export Board 66.206.34.0/24 AS17787 PSEB-AS-PK Pakistan Software Export Board 66.206.35.0/24 AS17787 PSEB-AS-PK Pakistan Software Export Board 66.206.40.0/22 AS174 COGENT Cogent/PSI 66.206.44.0/23 AS174 COGENT Cogent/PSI 66.206.47.0/24 AS17557 PKTELECOM-AS-AP Pakistan Telecom 66.207.32.0/20 AS23011 69.71.192.0/20 AS13818 PHX-INTL-TELEPORT - Phoenix International Teleport 69.80.0.0/17 AS3043 AMPHIB-AS - Amphibian Media Corporation 80.88.0.0/21 AS33774 DJAWEB 80.88.8.0/22 AS33774 DJAWEB 80.88.10.0/24 AS33774 DJAWEB 80.88.12.0/24 AS33779 wataniya-telecom-as 91.200.192.128/25 AS44045 DIGIEF-AS Didjief internation kulinari koncept LLC 91.200.193.128/25 AS44045 DIGIEF-AS Didjief internation kulinari koncept LLC 91.200.194.128/25 AS44045 DIGIEF-AS Didjief internation kulinari koncept LLC 91.200.195.128/25 AS44045 DIGIEF-AS Didjief internation kulinari koncept LLC 94.126.88.0/23 AS12695 DINET-AS Digital Network JSC 94.249.128.0/17 AS12586 ASGHOSTNET +------------------------------- 95.192.0.0/16 AS12654 RIPE-NCC-RIS-AS RIPE NCC RIS project 95.255.248.0/21 AS12654 RIPE-NCC-RIS-AS RIPE NCC RIS project 119.31.232.0/21 AS38870 121.50.12.0/24 AS38236 121.50.13.0/24 AS38236 121.50.14.0/24 AS38236 121.50.15.0/24 AS38236 137.0.0.0/13 AS721 DISA-ASNBLK - DoD Network Information Center 151.135.0.0/16 AS4768 CLIX-NZ TelstraClear Ltd 159.3.211.0/24 AS2687 ASATTCA AT&T Global Network Services - AP 163.142.0.0/16 AS2500 WIDE-BB WIDE Project 166.63.0.0/16 AS33775 NITEL-AS 172.7.0.0/24 AS28175 172.10.1.0/30 AS18305 POSNET POSDATA Co.,Ltd 188.0.0.0/16 AS12654 RIPE-NCC-RIS-AS RIPE NCC RIS project 188.0.0.0/21 AS12654 RIPE-NCC-RIS-AS RIPE NCC RIS project 188.0.0.0/24 AS12654 RIPE-NCC-RIS-AS RIPE NCC RIS project 192.9.200.0/24 AS3602 AS3602-RTI - Rogers Telecom Inc. 192.40.105.0/24 AS12582 TSF-DATANET-NGD-AS TSF MPLS VPN Services 192.64.85.0/24 AS1759 TSF-IP-CORE TeliaSonera Finland IP Network 192.69.107.0/24 AS1759 TSF-IP-CORE TeliaSonera Finland IP Network 192.69.108.0/24 AS1759 TSF-IP-CORE TeliaSonera Finland IP Network 192.69.177.0/24 AS1759 TSF-IP-CORE TeliaSonera Finland IP Network 192.70.164.0/24 AS25689 NRCNET-AS - National Research Council of Canada 192.96.36.0/24 AS5713 SAIX-NET 192.96.37.0/24 AS10474 NETACTIVE 192.96.135.0/24 AS2018 TENET-1 192.96.136.0/23 AS2018 TENET-1 192.96.141.0/24 AS2018 TENET-1 192.96.143.0/24 AS2018 TENET-1 192.96.145.0/24 AS2018 TENET-1 192.96.177.0/24 AS6083 POSIX-AFRICA 192.101.45.0/24 AS2905 TICSA-ASN 192.101.46.0/24 AS6503 Avantel, S.A. 192.101.47.0/24 AS6503 Avantel, S.A. 192.101.64.0/21 AS702 AS702 Verizon Business EMEA - Commercial IP service provider in Europe 192.101.70.0/24 AS701 UUNET - MCI Communications Services, Inc. d/b/a Verizon Business 192.101.71.0/24 AS701 UUNET - MCI Communications Services, Inc. d/b/a Verizon Business 192.101.72.0/24 AS702 AS702 Verizon Business EMEA - Commercial IP service provider in Europe 192.101.73.0/24 AS4765 WORLDNET-AS World Net & Services Co., Ltd. 192.101.74.0/24 AS1239 SPRINTLINK - Sprint 192.122.212.0/24 AS209 ASN-QWEST - Qwest 192.124.248.0/23 AS680 DFN-IP service G-WiN 192.124.252.0/22 AS680 DFN-IP service G-WiN 192.131.233.0/24 AS6389 BELLSOUTH-NET-BLK - BellSouth.net Inc. 192.133.6.0/24 AS10282 EQUANT-CEEUR EQUANT AS for Central and Eastern Europe region 192.153.144.0/21 AS721 DISA-ASNBLK - DoD Network Information Center 192.154.32.0/19 AS81 NCREN - MCNC 192.188.208.0/20 AS721 DISA-ASNBLK - DoD Network Information Center 193.25.240.0/21 AS3209 Arcor IP-Network 193.25.246.0/24 AS3211 Arcor Data-Network 193.200.114.0/23 AS31530 SERVERCREW-AS Servercrew LTD Autonomes System 193.218.205.224/27 AS41913 COMPUTERLINE Computerline, Schlierbach, Switzerland 194.31.227.0/24 AS21461 TRANSFAIRNET Transfair-net GmbH Krefeld 194.246.72.0/23 AS8893 ARTFILES-AS Artfiles New Media GmbH 196.6.108.0/24 AS5713 SAIX-NET 196.10.119.0/24 AS2018 TENET-1 196.10.122.0/23 AS2018 TENET-1 196.10.251.0/24 AS2018 TENET-1 196.10.252.0/23 AS2018 TENET-1 196.10.254.0/24 AS2018 TENET-1 196.13.101.0/24 AS2018 TENET-1 196.13.102.0/23 AS2018 TENET-1 196.13.104.0/24 AS2018 TENET-1 196.13.121.0/24 AS2018 TENET-1 196.13.125.0/24 AS2018 TENET-1 196.13.126.0/24 AS2018 TENET-1 196.13.169.0/24 AS2018 TENET-1 196.13.174.0/23 AS2018 TENET-1 196.13.176.0/21 AS2018 TENET-1 196.13.192.0/22 AS2018 TENET-1 196.13.196.0/24 AS2018 TENET-1 196.201.98.0/24 AS29571 CITelecom-AS 198.23.26.0/24 AS4390 BELLATLANTIC-COM - Bell Atlantic, Inc. 198.54.82.0/24 AS2018 TENET-1 198.54.92.0/24 AS2018 TENET-1 198.54.222.0/24 AS2018 TENET-1 198.97.72.0/21 AS721 DISA-ASNBLK - DoD Network Information Center 198.97.80.0/20 AS721 DISA-ASNBLK - DoD Network Information Center 198.97.96.0/19 AS721 DISA-ASNBLK - DoD Network Information Center 198.97.240.0/20 AS721 DISA-ASNBLK - DoD Network Information Center 198.144.96.0/20 AS12185 198.161.87.0/24 AS6539 GT-BELL - Bell Canada 198.167.0.0/16 AS7456 INTERHOP - Interhop Network SERVICES Inc. 198.168.0.0/16 AS701 UUNET - MCI Communications Services, Inc. d/b/a Verizon Business 198.169.0.0/16 AS803 SASKTEL - Saskatchewan Telecommunications 198.180.198.0/24 AS23715 SEOUL-INTGW-GXS-AP Global Exchange Services 199.9.128.0/17 AS668 ASN-ASNET-NET-AS - Defense Research and Engineering Network 199.10.0.0/16 AS721 DISA-ASNBLK - DoD Network Information Center 199.114.0.0/21 AS721 DISA-ASNBLK - DoD Network Information Center 199.114.128.0/18 AS721 DISA-ASNBLK - DoD Network Information Center 199.114.130.0/24 AS6045 DDN-ASNBLK - DoD Network Information Center 199.114.131.0/24 AS6045 DDN-ASNBLK - DoD Network Information Center 199.114.132.0/24 AS6045 DDN-ASNBLK - DoD Network Information Center 199.114.134.0/24 AS3541 ITSDN-U4 - DoD Network Information Center 199.114.136.0/24 AS27044 DDN-ASNBLK1 - DoD Network Information Center 199.114.138.0/24 AS6045 DDN-ASNBLK - DoD Network Information Center 199.114.140.0/24 AS3544 ITSDN-U7 - DoD Network Information Center 199.114.142.0/24 AS6045 DDN-ASNBLK - DoD Network Information Center 199.114.144.0/24 AS6045 DDN-ASNBLK - DoD Network Information Center 199.114.148.0/24 AS6045 DDN-ASNBLK - DoD Network Information Center 199.114.150.0/24 AS6045 DDN-ASNBLK - DoD Network Information Center 199.114.152.0/24 AS27033 DDN-ASNBLK1 - DoD Network Information Center 199.114.153.0/24 AS27034 DDN-ASNBLK1 - DoD Network Information Center 199.114.154.0/24 AS1733 CENTAF-SWA - 754th Electronic Systems Group 199.114.156.0/24 AS1733 CENTAF-SWA - 754th Electronic Systems Group 199.114.160.0/24 AS1733 CENTAF-SWA - 754th Electronic Systems Group 199.121.0.0/16 AS721 DISA-ASNBLK - DoD Network Information Center 199.123.0.0/18 AS721 DISA-ASNBLK - DoD Network Information Center 199.123.16.0/20 AS721 DISA-ASNBLK - DoD Network Information Center 199.123.80.0/21 AS721 DISA-ASNBLK - DoD Network Information Center 199.189.32.0/19 AS7332 IQUEST-AS - IQuest Internet 199.202.0.0/16 AS701 UUNET - MCI Communications Services, Inc. d/b/a Verizon Business 199.246.116.0/24 AS813 UUNET-CANADA - MCI Communications Services, Inc. d/b/a Verizon Business 202.58.113.0/24 AS19161 INNOCOM-TELECOM - INNOCOM TELECOM 202.73.144.0/20 AS4788 TMNET-AS-AP TM Net, Internet Service Provider 202.80.192.0/20 AS2706 HKSUPER-HK-AP Pacific Internet (Hong Kong) Limited 202.86.252.0/22 AS4748 RESOLINK-AS-AP Resources Link Network Limited 202.86.252.0/24 AS9304 HUTCHISON-AS-AP Hutchison Global Communications 202.86.253.0/24 AS9304 HUTCHISON-AS-AP Hutchison Global Communications 202.86.254.0/24 AS9304 HUTCHISON-AS-AP Hutchison Global Communications 202.86.255.0/24 AS9304 HUTCHISON-AS-AP Hutchison Global Communications 202.94.1.0/24 AS4808 CHINA169-BJ CNCGROUP IP network China169 Beijing Province Network 202.94.70.0/24 AS9837 POWERTEL-AP Powertel Ltd 202.124.195.0/24 AS17557 PKTELECOM-AS-AP Pakistan Telecom 202.136.254.0/24 AS4808 CHINA169-BJ CNCGROUP IP network China169 Beijing Province Network 202.136.255.0/24 AS4808 CHINA169-BJ CNCGROUP IP network China169 Beijing Province Network 202.181.32.0/24 AS4645 ASN-HKNET-AP HKNet Co. Ltd 203.12.45.0/24 AS4854 NETSPACE-AS-AP Netspace Online Systems 203.62.0.0/17 AS7575 AARNET-AS-AP Australian Academic and Reasearch Network (AARNet) 203.78.48.0/20 AS9299 IPG-AS-AP Philippine Long Distance Telephone Company 203.89.139.0/24 AS17911 BRAINPK-AS-AP Brain Telecommunication Ltd. 203.111.192.0/20 AS7473 SINGTEL-AS-AP Singapore Telecom 203.112.111.0/24 AS7474 OPTUSCOM-AS01-AU SingTel Optus Pty Ltd 203.112.113.0/24 AS7474 OPTUSCOM-AS01-AU SingTel Optus Pty Ltd 203.112.114.0/24 AS4802 ASN-IINET iiNet Limited 203.112.116.0/24 AS7474 OPTUSCOM-AS01-AU SingTel Optus Pty Ltd 203.112.117.0/24 AS7474 OPTUSCOM-AS01-AU SingTel Optus Pty Ltd 203.112.118.0/24 AS7474 OPTUSCOM-AS01-AU SingTel Optus Pty Ltd 203.112.119.0/24 AS7474 OPTUSCOM-AS01-AU SingTel Optus Pty Ltd 203.112.120.0/24 AS7474 OPTUSCOM-AS01-AU SingTel Optus Pty Ltd 203.112.121.0/24 AS7474 OPTUSCOM-AS01-AU SingTel Optus Pty Ltd 203.112.127.0/24 AS7474 OPTUSCOM-AS01-AU SingTel Optus Pty Ltd 203.128.128.0/19 AS4134 CHINANET-BACKBONE No.31,Jin-rong Street 203.128.128.0/24 AS23849 CNNIC-NET263-AP Beijing Capital-online science development Co.,Ltd. 203.160.110.0/23 AS7643 VNN-AS-AP Vietnam Posts and Telecommunications (VNPT) 204.9.216.0/23 AS6389 BELLSOUTH-NET-BLK - BellSouth.net Inc. 204.9.217.0/24 AS4323 TWTC - tw telecom holdings, inc. 204.9.218.0/23 AS6389 BELLSOUTH-NET-BLK - BellSouth.net Inc. 204.13.140.0/22 AS7270 NET2PHONE - Net2Phone Corp. 204.16.120.0/23 AS12077 204.16.122.0/23 AS12077 204.19.14.0/23 AS577 BACOM - Bell Canada 204.48.58.0/24 AS4323 TWTC - tw telecom holdings, inc. 204.48.60.0/24 AS4323 TWTC - tw telecom holdings, inc. 204.154.125.0/24 AS3952 TELLABS-ASN - TELLABS Operations, Inc. 204.154.126.0/24 AS3952 TELLABS-ASN - TELLABS Operations, Inc. 204.154.127.0/24 AS3952 TELLABS-ASN - TELLABS Operations, Inc. 205.144.160.0/20 AS7296 ALCHEMYNET - Alchemy Communications, Inc. 205.150.0.0/15 AS701 UUNET - MCI Communications Services, Inc. d/b/a Verizon Business 206.162.224.0/19 AS23464 ILCSNET - Interlink Computer Services 206.180.240.0/20 AS12083 KNOLOGY-NET - Knology Holdings 206.220.240.0/24 AS10764 STARTAP - National Center for Supercomputing Applications 206.220.240.64/26 AS22335 MREN - Metropolitan Research and Education Network 206.220.240.128/25 AS10764 STARTAP - National Center for Supercomputing Applications 206.220.240.220/32 AS10764 STARTAP - National Center for Supercomputing Applications 206.220.241.0/24 AS10764 STARTAP - National Center for Supercomputing Applications 207.98.209.0/24 AS701 UUNET - MCI Communications Services, Inc. d/b/a Verizon Business 207.98.223.0/24 AS701 UUNET - MCI Communications Services, Inc. d/b/a Verizon Business 207.191.128.0/19 AS10887 BPSI-AS - BPSI Internet Services 207.204.168.0/24 AS15150 BELLTECH-AS - BELLWETHER TECHNOLOGY CORPORATION 207.204.222.0/24 AS22773 CCINET-2 - Cox Communications Inc. 207.231.96.0/19 AS11194 NUNETPA - NuNet Inc. 208.38.192.0/21 AS14237 BEAMSPEED1 - Beamspeed 208.38.202.0/24 AS14237 BEAMSPEED1 - Beamspeed 208.38.203.0/24 AS14237 BEAMSPEED1 - Beamspeed 208.38.204.0/22 AS14237 BEAMSPEED1 - Beamspeed 209.54.93.0/24 AS22773 CCINET-2 - Cox Communications Inc. 209.54.111.0/24 AS22773 CCINET-2 - Cox Communications Inc. 209.54.123.0/24 AS6062 NETPLEX - NETPLEX 209.54.240.0/21 AS10887 BPSI-AS - BPSI Internet Services 209.74.96.0/19 AS10912 INTERNAP-BLK - Internap Network Services Corporation 209.74.96.0/20 AS16776 MOVE-CORP - Move Sales, Inc. 209.74.112.0/20 AS16776 MOVE-CORP - Move Sales, Inc. 209.140.90.0/24 AS14461 NTSL - NET SOLUTIONS 209.140.224.0/21 AS10573 WEBNEXUS - WebNexus Communications Inc. 209.140.234.0/24 AS10573 WEBNEXUS - WebNexus Communications Inc. 209.140.235.0/24 AS10573 WEBNEXUS - WebNexus Communications Inc. 209.140.236.0/24 AS10573 WEBNEXUS - WebNexus Communications Inc. 209.140.237.0/24 AS10573 WEBNEXUS - WebNexus Communications Inc. 209.140.238.0/24 AS10573 WEBNEXUS - WebNexus Communications Inc. 209.140.239.0/24 AS10573 WEBNEXUS - WebNexus Communications Inc. 209.141.16.0/21 AS10573 WEBNEXUS - WebNexus Communications Inc. 209.141.48.0/22 AS14461 NTSL - NET SOLUTIONS 209.145.192.0/18 AS3043 AMPHIB-AS - Amphibian Media Corporation 210.5.128.0/20 AS4837 CHINA169-BACKBONE CNCGROUP China169 Backbone 216.37.114.0/23 AS3549 GBLX Global Crossing Ltd. 216.37.120.0/23 AS13377 216.59.0.0/17 AS3356 LEVEL3 Level 3 Communications 216.99.16.0/24 AS6395 LVLT-6395 - Level 3 Communications, Inc. 216.99.20.0/24 AS6395 LVLT-6395 - Level 3 Communications, Inc. 216.127.124.0/23 AS2828 XO-AS15 - XO Communications 216.162.96.0/19 AS7393 CYBERCON - CYBERCON, INC. 216.172.198.0/24 AS22773 CCINET-2 - Cox Communications Inc. 216.172.199.0/24 AS22773 CCINET-2 - Cox Communications Inc. 216.210.86.0/24 AS577 BACOM - Bell Canada 216.229.51.0/24 AS15211 216.240.240.0/24 AS7018 ATT-INTERNET4 - AT&T WorldNet Services 216.240.241.0/24 AS7018 ATT-INTERNET4 - AT&T WorldNet Services 216.240.242.0/24 AS7018 ATT-INTERNET4 - AT&T WorldNet Services 216.251.207.0/24 AS1239 SPRINTLINK - Sprint 217.78.71.0/24 AS12491 IPPLANET-AS IPPlanet 217.78.72.0/24 AS12491 IPPLANET-AS IPPlanet 217.78.73.0/24 AS12491 IPPLANET-AS IPPlanet Please see http://www.cidr-report.org for the full report ------------------------------------ Copies of this report are mailed to: nanog(a)merit.edu eof-list(a)ripe.net apops(a)apops.net routing-wg(a)ripe.net afnog(a)afnog.org

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Anyone have experience with Alcatel 9500MXC?
by Tom Storey 19 Sep '08

19 Sep '08

Hi all. I have several of these units deployed, they are all running fine, but I am looking for information about them, specifically SNMP related. Our Alcatel contacts have given us a collection of MIBs, from which I cant really get anything useful out of the radios. Other than that they dont seem too hell bent on providing much further help on this subject. Hoping someone else on here might have experience with these units and can share some information about how to get useful information out of them via SNMP, like traffic and error counters, signal parameters, alarm status, etc. Cheers, Tom

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Re: Mechanisms for a multi-homed host to pick the best router
by Brighten Godfrey 19 Sep '08

19 Sep '08

> When the server sends TCP traffic for that same connection back to > host A, > it needs to pick one of the N routers, in other words, it needs to > pick an > outbound interface from its N interfaces. ... > The problem is that some routers are "better" than other routers in > the > sense that they are closer to the final destination address A. (For > example, > each router could be connected to a different ISP.) > > One way for the server to pick the "optimal" downstream router, is > to run > "stub BGP" between the server and each of the routers. ... > While this approach would certainly allow the server to pick the > optimal > downstream router in all cases, I would prefer not to run routing > protocols > on this server for a number of reasons: It's probably good to keep in mind that this would be "optimal", not optimal. As far as I know the best you would get is to minimize the number of AS hops, which is probably correlated with, but definitely not the same as, metrics you actually care about like latency. All in all, running BGP does seem like an awful lot of work just to let you optimize for the wrong metric. Here's another thought, though. You don't need to run BGP to get the data that BGP will give you. There exist approximate maps of the Internet at the router or AS level with IP prefixes attached. It would be possible to periodically obtain one of these graphs, e.g. from CAIDA, and then run a shortest-paths algorithm on that graph to decide based on the destination IP address which router is best. Not only does this let you avoid running BGP, it also saves memory since you need only one copy of the graph, rather than one copy for each of the N BGP sessions. Of course, it's not real-time data, but if all you need is a good guess as to which of the outbound interfaces is best, it might be sufficient. Does anyone actually do something like this in practice? (I'm guessing no) > Someone suggested an idea to me which seems almost to simple to > work, but I > cannot find any good reason why it would not work. > > The idea is "the server simply sends all outbound traffic for the TCP > connection out over the same interface over which the most recent TCP > traffic for that connection was received". So the underlying idea here is that the source (or its ISP) has effectively done the work of picking a good path, and by replying on the same interface, you use the reverse of that path, which is also likely to be pretty good. Some of the assumptions in that reasoning seem imperfect: - There's a good chance the forward path (i.e. the one the source picked) isn't the best. - Asymmetry, as you noted: Even if the forward path was the best, the reverse of it is not necessarily the best. - A different asymmetry: Even if the forward was best and the reverse of it is best, the path followed by sending on the same interface is not necessarily the reverse of the forward path. So I understand that this heuristic could perform pretty well in practice, and certainly better than sending on a random interface (in terms of latency, not traffic engineering). But I can't see how it's the optimal strategy. I think there are commercial products that solve this problem the "right" way, by automatically and dynamically monitoring path quality and availability, and selecting paths for you. I think the Avaya Converged Network Analyzer is one. I recall speaking with an operator from a major content provider who said that they use an intelligent route selection product similar to this for their outbound traffic. I'd be personally interested to hear what other operators typically use. ~Brighten Godfrey

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Procedure to Change Nameservers
by Crist Clark 19 Sep '08

19 Sep '08

This should be easy. But sometimes things that seem like they should be easy are not. I want to change the nameservers for a bunch of domains. Really, all I want to do is change the IP address, but it seems easier just to change both the name and IP to avoid any possibility of confusion. However, I am not "physically" moving the services. These are the same physical servers, just an additional IP address assigned to the appropriate interface. I want to do this the "right" way. Here's what I want to do. Am I doing anything wrong? (Am I being way too careful?) For the example, let's use the names, old-dns1, new-dns1, old-dns2, and new-dns2. I think you can guess what they mean. 1) Add new-dns1 and new-dns2 to the NS records for a domain. (Possible problem: I have NS records in my authorative DNS for the zone that are not in the hints at the gTLD server level. But that's not really a problem, right? They are not lame servers.) 2) Change the NAMESERVER entries at the registrar from old-dns1 to new-dn1 and old-dns2 to new-dns2. 3) Wait for the change to be reflected in the gTLD servers. 4) Wait for the TTL on the records to expire. 5) Wait a little bit longer just to be safe (maybe do some query logging to see who still is using the old ones). 6) Remove old-dns1 and old-dns2 NS records from the zone. 7) Wait for the TTL on the records to expire. 8) Wait a bit longer. 9) Turn off DNS services at old-dns1 and old-dns2 (i.e. take out the firewall rules that allow queries to those addresses). 10) ... 11) Profit. Not really too bad. At least we don't have to send in host record templates anymore. B¼information contained in this e-mail message is confidential, intended only for the use of the individual or entity named above. If the reader of this e-mail is not the intended recipient, or the employee or agent responsible to deliver it to the intended recipient, you are hereby notified that any review, dissemination, distribution or copying of this communication is strictly prohibited. If you have received this e-mail in error, please contact postmaster(a)globalstar.com

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Mechanisms for a multi-homed host to pick the best router
by Cayle Spandon 18 Sep '08

18 Sep '08

(My apologies, in advance, for the fact that this question is very long winded.) I have a server which is multi-homed to N routers as shown below: +---+ R1---| | | | R2---| | ... | S | | | Rn---| | +---+ This server is a host; it is not a router in the sense that it will never forward any packets (but it might run routing protocols as discussed below). Also, for the sake of simplicity in this discussion, let's say this server only receives inbound TCP connections; it never initiates outbound TCP connections. Finally, this server has a loopback address L. All traffic destined to the server uses address L as the destination address. All N routers have a static route to L and inject that route into their routing protocol (possibly as part of an aggregate). Now, imagine the server receives an inbound connection from another host whose address is A. Thus, the TCP SYN packet which S receives has source address A and destination address L. When the server sends TCP traffic for that same connection back to host A, it needs to pick one of the N routers, in other words, it needs to pick an outbound interface from its N interfaces. Traditionally, this is done by doing a best-match lookup for address A in the forwarding table of the server. One could install a ECMP default route which points to all N routers. In this case, the downstream router would essentially be picked at random (for each connection, assuming 5-tuple hashing). The problem is that some routers are "better" than other routers in the sense that they are closer to the final destination address A. (For example, each router could be connected to a different ISP.) One way for the server to pick the "optimal" downstream router, is to run "stub BGP" between the server and each of the routers. By "stub BGP" I mean that the server uses the BGP session only to learn routes. It advertises its own loopback L, but it never advertises any other routes, and it never propagates and routes from one BGP session to another BGP session. The server would have N BGP sessions and learn the full default-free BGP route table over each of those sessions. In other words, the server would end up with approximately N x 250,000 routes in its RIB and 250,000 routes in its FIB. While this approach would certainly allow the server to pick the optimal downstream router in all cases, I would prefer not to run routing protocols on this server for a number of reasons: - I don't want to the spend memory and CPU on such large RIBs and FIBs. - I'm afraid that other routers will attempt to forward traffic through the server (due to accidental misconfigurations) once it starts participating in the routing protocols. - Since there might be many of these servers (many more than the number of routers) I might end up stretching the routers beyond their scaling limits (number of BGP sessions, link state database size, etc.) and destabilizing the network. - I know there are good open source implementation of routing protocols, but still, I'm nervous that any instability or bugs on the servers could end up screwing up the routers (e.g. persistent BGP flaps). - One possible variation is that the server is a client of some route-reflectors which are not in the forwarding path (i.e. next-hop-self is not enabled). In that case, I might end up needing to do BGP next-hop resolution for a very large number of BGP next-hops. This, in turn, implies that the server might need to also run OSPF in a very large flat area 0. For all these reasons, I don't want to run BGP on the server. Someone suggested an idea to me which seems almost to simple to work, but I cannot find any good reason why it would not work. The idea is "the server simply sends all outbound traffic for the TCP connection out over the same interface over which the most recent TCP traffic for that connection was received". So, for example, if the server receives the SYN from router R3, it would send the SYN ACK and all subsequent packets for the TCP connection over that same interface R3. If the inbound packets for that same TCP connection start arriving from a different router (e.g. because of link failure), say R4, then the server also switches the outbound packets to that same router R4. I am aware that routing is not always symmetrical. In other words, I am aware that the best route from A to Z might be A->B->C->Z while the best route from Z to A might be Z->D->A. However, since the IP routing tables form an inverted tree, it seems to me that in realistic scenarios the traffic should still arrive at A (maybe over a non-optimal path in rare cases) if Z sends the reverse traffic to C instead of D. It seems unlikely (impossible?) that this would cause a routing loop. I can think of the following problems with this approach: (Problem 1) It only works for inbound TCP connections and not for outbound TCP connections. For outbound TCP connections we would not know which router to send the first SYN packet to. (Problem 2) If there is a topology change after the TCP connection has been established, the traffic might follow a sub-optimal path. In extreme cases, after a topology change the TCP connection might be lost despite the availability of an alternative feasible path. For example, if server S is using router R1 to reach host A, and router R1 can no longer reach host A, and host A is not sending *any* traffic to server S, then server S is not going to find out about the topology change (since S doesn't receive any traffic from A), and the connection is going to be dropped (because S's retransmission will never reach A). Many application layer protocols have a keep-alive message at the application layer; in that case the problem would not occur because host A would always be sending some traffic to server S which would allow S to discover the topology change by virtue of A's traffic arriving from a different router. My question for the NANOG community are these: (Question 1) Can you think of any additional problems with this approach? Specifically, I am interested in persistent failures in the absence of topology changes. (Question 2) Is there another mechanism for the server (a multi-homed host) to pick a best router, short of running stub BGP? Are there any standards for this? (Question 3) If the answer to question 2 is "no", is there any interest in standardizing a protocol for a multi-homed host to pick a best next-hop router? One could think of this is a host-to-router routing protocol. One might call the existing routing protocols router-to-router protocols (because I think we are abusing them by running them on hosts). This is somewhat analogous to the multicast routing world where we use different protocols for router-to-router multicast (PIM) versus host-to-router (IGMP). -- Cayle

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