[e2e] topological locality of Internet communication?

Panos TRIMINTZIOS p.trimintzios at eim.surrey.ac.uk
Fri Nov 5 03:43:18 PST 2004

Information about AS Paths from routes advertised with BGP on the
average/maximum AS path length (maybe also taking into account AS Path
prepending statistics) is an indication of the "AS hops" a typical
connection may cross in the Internet. Currently I the average AS Path
size is around 3.5 AS hops, while the maximum 11-12.

An analysis of the various BGP reports given in:
can give you a reasonable indication for the "AS hops" statistics you
need for your simulations.

-Panos Trimintzios

On Thu, 4 Nov 2004, Lars Eggert typed:

// Hi,
// since we were just talking about Internet statistics:
// I'm looking to get a feel of how much topological locality Internet
// communication exhibits, to calibrate some simulations we plan to run.
// Is anyone aware of measurements of how many "AS hops" typical
// connections cross in the Internet? Ideal would be a CDF of "AS hops
// crossed" for connection percentages.
// (I thought about looking at the TTLs of incoming TCP packets at servers,
// infering the OS based on TCP characteristics like nmap and using this to
// guess the default outbound TTL for that OS. But that yields IP hops, not
// AS hops.)
// Thanks,
// Lars
// --
// Lars Eggert                                     NEC Network Laboratories

 Panos Trimintzios
 Research Fellow, Networks Research Group
 Centre for Communication Systems Research (CCSR)
 Univ. of Surrey, Guildford, Surrey GU2 7XH, U.K.
 Tel: +44 (0)1483 686005  Fax: +44 (0)1483 686011
 Email: <p.trimintzios at eim.surrey.ac.uk>

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