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INTRODUCTION
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This directory contains AS links annotated with inferred relationships.
Each file contains a full AS graph derived from a set of RouteViews
BGP table snapshots.

Please cite this dataset as follows:

  The CAIDA AS Relationships Dataset, <date range used>.
  http://www.caida.org/data/active/as-relationships/

For more information, email topology-info@caida.org.

The general procedure for creating a file is as follows:

  1. Extract all AS links from RouteViews snapshots.

  2. Infer customer-provider relationships, and annotate AS links.

  3. Infer peer-to-peer relationships, and annotate AS links, possibly
     overriding customer-provider relationships inferred in step 2.

  4. Heuristically fix suspicious looking inferred relationships
     (e.g., a low-degree AS acting as provider to a high-degree AS).

  5. Infer sibling ASes (that is, ASes belonging to the same organization)
     from WHOIS, and annotate AS links, possibly overriding previous
     relationship annotations.


For further details see

 * Xenofontas Dimitropoulos, Dmitri Krioukov, Marina Fomenkov,
   Bradley Huffaker, Young Hyun, kc claffy, and George Riley,
   "AS Relationships: Inference and Validation", in submission to
   ACM CCR (Computer Communication Review).
   http://www.caida.org/publications/papers/2006/as_relationships_inference/ 

 * Xenofontas Dimitropoulos, Dmitri Krioukov, Bradley Huffaker,
   kc claffy, and George Riley, "Inferring AS Relationships: Dead End
   or Lively Beginning?", 4th Workshop on Efficient and Experimental
   Algorithms (WEA), LNCS v3503, 2005.
   http://www.caida.org/publications/papers/2005/asrelationships/

 * http://as-rank.caida.org


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FORMAT
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Files are line oriented.  Each line contains one AS link or a comment,
with comments introduced by '#'.  The format of a line containing a link
is as follows:

   <AS1> <AS2> <relationship>

where

  <AS1> and <AS2> are AS numbers, and
  <relationship> is -1 if AS1 is a customer of AS2,
                     0 if AS1 and AS2 are peers,
                     1 if AS1 is a provider of AS2, and
                     2 if AS1 and AS2 are siblings (the same organization).

For example:

3300 12491 1
12491 3300 -1
16815 12182 -1
15658 3277 0


   NOTE: There will always be two links listed for each pair of ASes
         engaged in some relationship.  For example, suppose the ASes
         X and Y are engaged in a provider-customer relationship.
         Then there will be a provider-to-customer link X -> Y and a
         customer-to-provider link Y -> X listed in a file.  If the
         relationship is peer-to-peer, then both the X -> Y and Y -> X
         links listed in a file will be peer-to-peer (the same applies
         to sibling-to-sibling links).

         For instance, in the above example, AS3300 and AS12491 are in
         a provider-customer relationship.  There are, therefore, a
         provider-to-customer link from AS3300 to AS12491

            3300 12491 1

         and a customer-to-provider link from AS12491 to AS3300

            12491 3300 -1.