Re: The Cidr Report

  • To: bmanning at isi dot edu (Bill Manning)
  • Subject: Re: The Cidr Report
  • From: Tony Bates <tbates at cisco dot com>
  • Date: Sun, 01 Dec 1996 15:57:07 -0800
  • Cc: randy at psg dot com (Randy Bush), pferguso at cisco dot com, nanog at merit dot edu, eof-list at ripe dot net, apops at apnic dot net
  • In-reply-to: Your message of Sat, 30 Nov 1996 10:45:47 PST. <199611301845.AA08115 at zephyr dot isi dot edu>
  • Sender: owner-apops@apnic.net
    • 
      Well I did a bit of digging at the sudden difference we are seeing. A
      lot of this points to different levels of aggregation at different
      points in the Internet. I took a dump from Bill's box at ?LA? and from the
      xara.net router I use at Mae-east and saw one immediate example of
      this. Here's the prefixes announced out of the 206.16/16 (belongs to
      CERFNET) block.
      
      First from xara.net (12 prefixes)
      ---------------------------------
      
      206.16.0.0/16 in AS1740
      206.16.192.0/18 in AS6077
      206.16.96.0 in AS6332
      206.16.97.0 in AS6332
      206.16.98.0 in AS6332
      206.16.99.0 in AS6332
      206.16.102.0 in AS6332
      206.16.105.0 in AS6332
      206.16.106.0 in AS6332
      206.16.111.0 in AS6332
      206.16.112.0 in AS6332
      206.16.113.0 in AS6332
      
      Then Bill's router (59 prefixes)
      --------------------------------
      
      206.16.12.0 in AS4262
      206.16.16.0 in AS4262
      206.16.18.0 in AS1740
      206.16.20.0 in AS1740
      206.16.21.0 in AS1740
      206.16.22.0 in AS1740
      206.16.23.0 in AS1740
      206.16.26.0 in AS1740
      206.16.29.0 in AS1740
      206.16.32.0 in AS4262
      206.16.40.0 in AS4262
      206.16.41.0 in AS4262
      206.16.42.0 in AS4262
      206.16.44.0 in AS4262
      206.16.47.0 in AS4262
      206.16.48.0 in AS4262
      206.16.74.0 in AS4262
      206.16.77.0 in AS4262
      206.16.78.0 in AS4262
      206.16.81.0 in AS4262
      206.16.82.0 in AS4262
      206.16.85.0 in AS4262
      206.16.86.0 in AS4262
      206.16.87.0 in AS4262
      206.16.90.0 in AS1740
      206.16.91.0 in AS1740
      206.16.92.0 in AS1740
      206.16.93.0 in AS1740
      206.16.94.0 in AS4262
      206.16.95.0 in AS1740
      206.16.96.0 in AS1740
      206.16.96.0 in AS6332
      206.16.97.0 in AS6332
      206.16.98.0 in AS6332
      206.16.99.0 in AS6332
      206.16.100.0 in AS1740
      206.16.102.0 in AS6332
      206.16.105.0 in AS1740
      206.16.105.0 in AS6332
      206.16.106.0 in AS6332
      206.16.107.0 in AS1740
      206.16.108.0 in AS1740
      206.16.109.0 in AS1740
      206.16.111.0 in AS6332
      206.16.112.0 in AS6332
      206.16.113.0 in AS6332
      206.16.140.0 in AS4262
      206.16.141.0 in AS4262
      206.16.142.0 in AS4262
      206.16.143.0 in AS4262
      206.16.150.0 in AS1740
      206.16.160.0 in AS1740
      206.16.188.0 in AS1740
      206.16.0.0/16 in AS1740
      206.16.10.0/23 in AS4262
      206.16.136.0/22 in AS4262
      206.16.168.0/21 in AS4262
      206.16.176.0/22 in AS4262
      206.16.192.0/18 in AS6077
      
      This is not to pick on CERFNET but just to highlight a problem of
      actually tracking the size of the routing table in general. This 
      CERFnet case seems to be this way becuase it is a direct peer of
      Bill's box even though I can see no reason why the more specifics are
      needed.
      
      Looking a little more it seems a large amount of more specifics are being
      announced to Bill's boxe which aren't being announced to the xara.net
      router. Perhaps ISPs are taking more care at places like MAE-East with
      their outbound filters than they are at Bill's peering point even though
      Bill only has 6 active EBGP neighbors and the xara.net router has 39
      ;-(.
      
      At this point I am pretty happy with using a well connected box at
      MAE-East as the point of reference. Bill, if you want to start your
      own your collection and make the data available feel free from your
      vantage piont. 
      
      		--Tony
      
      
       bmanning@ISI.EDU (Bill Manning) writes:
        * > 
        * > > This is what I see from this neck of the woods:
        * > 
        * > which is not very useful with no historical data.
        * > 
        * 
        * 	True enough.  Perhaps tony would be willing
        * 	to share his methods so the results may be
        * 	comparable.  I've got about two months worth
        * 	of data off sandbax.
        * 
        * 
        * -- 
        * --bill