AS paths to individual networks

AS paths to individual networks

24 November 1997, HWB

Information such as described in http://moat.nlanr.net/AS/background.html can be used to construct AS paths from the BGP peers to a specific target network. This can be useful to determine disjoint paths and where they converge.

For example, using 192.9.9.100 as an IP address of the www.sun.com web server, the BGP tables yield the following path information:

     Network          Next Hop       M/LP/Weight Path
  *  192.9.9.0        204.212.44.128           0 234 266 237 3561 701 90 i
  *                   205.238.48.3             0 2914 1 90 i
  *                   144.228.240.93           0 1239 701 90 i
  *                   204.70.4.89              0 3561 1 90 i
  *                   194.68.130.254           0 5459 5413 1 90 i
  *>                  134.24.127.3             0 1740 701 90 i
  *                   202.232.1.8              0 2497 701 90 i
  *                   158.43.133.48            0 1849 702 701 90 i
  *                   131.103.20.49            0 1225 2548 1 90 i

With the next hops being:

  blackrose.org (Ann Arbor)     204.212.44.128  through AS234
  Verio         (MAE-WEST)      205.238.48.3    through AS2914
  Sprint        (Stockton)      144.228.240.93  through AS1239
  MCI           (San Francisco) 204.70.4.89     through AS3561
  LINX          (London)        194.68.130.254  through AS5459
  CERFnet       (San Diego)     134.24.127.3    through AS1740
  IIJ           (Japan)         202.232.1.8     through AS2497
  PIPEX         (London)        158.43.133.48   through AS1849
  IAGnet        (Chicago)       131.103.20.49   through AS1225

For the target network number (192.9.9.0) all paths converge via AS 90 (SUN-AS), via either AS 701 (ALTERNET-AS) or AS 1 (BBNPLANET).

A potential for a visualization (similar to http://moat.nlanr.net/AS/background.html) maps Autonomous Systems as nodes on the surface of a sphere, and then interconnect via reachability paths. The following visualization attempts to to this, by then also mapping the nine BGP peers (which exchange data with the server in Oregon) onto a site of the sphere opposite the target AS number (90).

The graphic shows the (green) Oregon server on the left site, connected to the (purple) BGP sites, from where then the paths emerge via (yellow) pipes and (red) Autonomous System spheres at the inside of the (blue, transparent) system sphere, towards the (green) target network.

A short MPEG (183,739 bytes) animation, only 50 frames (sorry, ran out of time), shows a fly-through path traversing the sphere. Same as motion GIF (1,735,722 bytes).


Visualization steps: