Routing

• AS statistics Jan 1 2007

  o Number of single-homed ASes.
           RIS       rrc00       rrc01
  ARIN    3916        4908        4123
  APNIC    761         878         896
  RIPENCC 2786        3398        3558
  LACNIC   116         135         141
  AFRINIC   17          17          12
  IANA       0           0           0
  Private   43          24          17
  Others     0           0           0
  Total   7639        9360        8747
  
  o Number of multi-homed ASes.
           RIS       rrc00       rrc01
  ARIN    8300        7281        4684
  APNIC   2035        1905        1649
  RIPENCC 6268        5607        4709
  LACNIC   159         139         110
  AFRINIC   13          13          11
  IANA       0           0           0
  Private   28          25           8
  Others     0           0           0
  Total  16804       14971       11172
  
  o Distribution of AS number wrt Leaf, Transit.
                   RIS     rrc00       rrc01
  Leaf           20397     20454       16395
  Transit         3917      3753        3244
  Transit-only     135       129         282
  Total          24449     24336       19921
  

• ClosestNode: "directing clients to servers and peers that are close to them"
• Route control: guiding how packets leave a multi-homed enterprise ("iBGP whispers"):
  • RouteScience
  • sockeye: uses the Akamai systems to gather info on network delays and congestion points.
  • Radware: NAT-like translation to shift load
  • Internap: connects a single access line from the customer premises to a proprietary POP, which then connects to the Tier 1 ISPs.
  • Firefox AS Number Extension: "The AS Number Extension displays the AS Number, and consequently the Internet Service Provider, of every website visited along with some additional interesting information for those interested in how the Internet works below the shiny surface."
  • NPN: Multihoming and Route Optimization: Finding the Best Way Home, Network Magazine, Feb. 2002
• Global Routing Instabilities during Code Red II and Nimda Worm Propagation, September 2001, by James Cowie, Andy Ogielski, BJ Premore and Yougu Yuan.
• Olivier Bonaventure wrote on the MPLS mailing list in September 2000 that

  Some time ago, we looked at the BGP routing table of the Belgian research ISP and found a similar result. We looked at the number of reachable IP addresses (i.e. IP addresses announced through BGP) and found that most addresses were between two and 5 AS away from our small ISP.

  LEVEL = 1  ADDRESSES =  43131944
  LEVEL = 2  ADDRESSES = 177739421
  LEVEL = 3  ADDRESSES = 410798057
  LEVEL = 4  ADDRESSES = 347784802
  LEVEL = 5  ADDRESSES = 114262352
  LEVEL = 6  ADDRESSES =  14626560
  LEVEL = 7  ADDRESSES =    943360
  LEVEL = 8  ADDRESSES =    235264
  LEVEL = 9  ADDRESSES =      4352
  

• Analyzing the Internet's BGP Routing Table, Geoff Huston, December 2000.
• Background on Architectural Requirements for Inter-Domain Routing in the Internet, Geoff Huston, March 2001.
• James Aldridge's routing table on BGP aggregation and growth
• IRTF web page
• NIMROD; archives
• Route Server Peering Configuration Viewer
• Graphical representation of peering points
• VisualRoute: shows route from and to a designated route server
• Hermes explores AS relationships through an applet
• prtraceroute is a traceroute-like tool that lists AS. Traversal of 4-5 ASs seems typical, with up to 9 (columbia.edu to ntua.gr) seen. whois -h whois.radb.net 128.59.0.0 also returns contact address, prefix and AS information.
• List of traceroute servers
• Enhanced version of prtraceroute
• AS1221 BGP Table Data (routing table size, appr. 87,000 entries)
• University of Oregon Route Views Project: "the Route Views router, route-views.oregon-ix.net, uses multi-hop BGP peering sessions (configuration) with backbones at interesting locations"; BGPlay "is a Java application which displays animated graphs of the routing activity of a certain prefix within a specified time interval."
• IPMA routing table snapshots.
• MAE-East looking glass
• 3Com: Corebuilder 3500: 3.6 Mp/s (130 pps/$); Bay Backbone Node: 1 Mp/s (4 pps/$); Cisco 7500: 230 kp/s (1 pps/$).
• List of remote traceroute services

Autonomous Systems (AS)

• IANA assigns ranges of AS numbers.
• ARIN whois tool that looks up AS numbers.
• AS path lengths: about 95% of routes are six or fewer AS long, including the source and destination AS. Almost no paths have 9 or more ASes.