On Oct 4, 2007, at 11:58 AM, bmanning@vacation.karoshi.com wrote:
one: AS hop count for average e2e packet flow, eg. from origin to destination, how many ASN's will a packet traverse?
You might look at Figure 8c of http://www.multicasttech.com/status/ If you assume that destinations IP addresses are selected at random, that tells you the PDF of the AS hop counts from here. The mode is 3 hops. Here is the data for Noon EDT, in case you want to do more. # hops = Number of transit AS hops required to reach the source from AS 16517 ## hop_histogram Unicast AS Hop Histogram ## hop_histogram Number of Hops | Number of ASN | Number of Prefixes | Address Space Used ## hop_histogram # hop_histogram 1 1 968 2.78565e+07 # hop_histogram 2 1587 32780 7.74648e+08 # hop_histogram 3 12829 122320 1.06436e+09 # hop_histogram 4 8754 56473 2.98075e+08 # hop_histogram 5 2549 14877 4.19192e+07 # hop_histogram 6 432 1932 1.18231e+07 # hop_histogram 7 39 215 872786 # hop_histogram 8 6 32 50112 # hop_histogram 9 0 0 0 # hop_histogram 10 0 0 0 # hop_histogram 11 0 0 0 # hop_histogram 12 0 0 0 # hop_histogram 13 0 0 0 # hop_histogram 14 1 1 4094 This of course is polluted somewhat by as path prepending, which could be stripped off if desired. Regards Marshall
two: number/location of IX that monitor/forbid transit across exchange fabric?
--bill (doing grunt work for a study on Landauer Entropy)