/24's run amuck?

Richard A. Steenbergen ras at e-gerbil.net
Tue Feb 6 19:30:58 UTC 2001


I noticed something interesting the other day... /24's seem to be
contributing to the majority of the internet routing table today. Here is
the breakdown right now as viewed through GlobalCrossing transit (the
view is consistent from many other sources):

Length /8:    23
Length /9:    4
Length /10:   5
Length /11:   10
Length /12:   32
Length /13:   59
Length /14:   194
Length /15:   304
Length /16:   6751
Length /17:   1003
Length /18:   2017
Length /19:   6275
Length /20:   4451
Length /21:   4316
Length /22:   6457
Length /23:   8429
Length /24:   58763
Length /25:   224
Length /26:   351

I was rather shocked by the number of /24's so I ran some further stats.
Here is the top 25 offenders by origin AS:

ASN:    701 routes:   1906 UUNet
ASN:   1221 routes:   1775 ??????
ASN:      1 routes:    606 BBN Planet
ASN:   2711 routes:    603 Rock Hill Telephone Company
ASN:   7018 routes:    599 AT&T
ASN:   7046 routes:    587 UUNet
ASN:   1785 routes:    546 Applied Theory
ASN:    705 routes:    537 UUNet
ASN:    174 routes:    508 PSInet
ASN:   8013 routes:    494 PSINet Canada
ASN:   2551 routes:    463 ICG NetAhead
ASN:   1239 routes:    453 Sprint
ASN:   3561 routes:    365 Cable and Wireless
ASN:   4293 routes:    355 Cable and Wireless
ASN:   2548 routes:    346 Digex
ASN:   2764 routes:    337 connect.com.au
ASN:   3602 routes:    313 Sprint Canada
ASN:    703 routes:    299 UUNet (Asia)
ASN:    209 routes:    292 Qwest
ASN:   2914 routes:    291 Verio
ASN:   3301 routes:    271 RIPE
ASN:    577 routes:    268 Bell Canada
ASN:   3908 routes:    261 Supernet, Inc.
ASN:    271 routes:    261 University of British Columbia
ASN:    724 routes:    258 DLA Systems Automation Center

Most of this waste seems to be coming from the Tier 2's, and for some
reason a large number of people doing things like 100/24, 102/24, 104/24,
etc, out of their larger netblocks. So here is a list considering the
entire AS path (note I can't give an accurate number for gblx), which
indicates those transiting the biggest offenders:

ASN:    701 routes:  17867 UUNet
ASN:   3967 routes:   8170 Exodus Communications
ASN:  10910 routes:   5948 InterNap
ASN:   1239 routes:   4967 Sprint
ASN:   3561 routes:   3095 Cable and Wireless
ASN:    209 routes:   3061 Qwest
ASN:   6461 routes:   2383 AboveNet Communications
ASN:    174 routes:   2347 PSInet
ASN:   1221 routes:   2343 ??????
ASN:   7018 routes:   2260 AT&T
ASN:   6453 routes:   2014 Teleglobe
ASN:   4355 routes:   1894 EarthLink
ASN:    702 routes:   1617 UUNet (Europe)
ASN:   5511 routes:   1480 Europe
ASN:   2548 routes:   1403 Digex
ASN:      1 routes:   1101 BBN Planet
ASN:    703 routes:   1095 UUNet (Asia)
ASN:    577 routes:    862 Bell Canada
ASN:   2711 routes:    814 TRW Huntsville
ASN:   2914 routes:    785 Verio
ASN:   3356 routes:    755 Level 3 Communications
ASN:   6347 routes:    717 SAVVIS Communications
ASN:   1785 routes:    715 Applied Theory
ASN:   7474 routes:    661 APNIC
ASN:    690 routes:    653 Merit Network     <-- bad merit, bad
ASN:   7046 routes:    588 UUNet
ASN:   4000 routes:    564 Sprint International
ASN:   8297 routes:    560 Europe
ASN:   4648 routes:    546 APNIC
ASN:    705 routes:    537 UUNet
ASN:   2828 routes:    506 Concentric
ASN:   8013 routes:    497 PSINet Canada
ASN:   3908 routes:    483 Supernet, Inc.
ASN:    724 routes:    476 DLA Systems Automation Center
ASN:   2551 routes:    472 ICG NetAhead
ASN:    286 routes:    457 EUNet
ASN:   4565 routes:    456 Epoch Networks
ASN:   7473 routes:    438 APNIC
ASN:   5650 routes:    438 Electric Lightwave
ASN:   2764 routes:    430 connect.com.au
ASN:   1913 routes:    409 Defense Logistics Agency
ASN:   3602 routes:    408 Sprint Canada
ASN:   2685 routes:    403 IBM
ASN:    816 routes:    401 UUNet Canada

BTW who is AS 1221? That block is listed as allocated by ARIN, but ARIN
has nothing in the whois for them.

I can produce a full list if anyone is interested. I'll see if I can
get a more accurate view for the aspath stats as well.

-- 
Richard A Steenbergen <ras at e-gerbil.net>       http://www.e-gerbil.net/ras
PGP Key ID: 0x138EA177  (67 29 D7 BC E8 18 3E DA  B2 46 B3 D8 14 36 FE B6)





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