Hi All, This is my first post to this list so please forgive me if it's in any way inappropriate, and as I know everyone has work to do, I'll try to be brief. I am a CS PhD student trying to track ASes (for reasons I'm happy to discuss offline). There is a grave inconsistency I have come across and can't explain. Simply, there seems to be many AS numbers in the non-private range that come into use at some point in time and advertise a range of IPs, but these AS numbers are not allocated until much later. More specifically, archived BGP tables show many AS numbers which ARIN shows not to have allocated (in their allocation history tables) until many months, sometimes a year/two, later. The number of such ASes has shrunk over time (from about 100 in 1999/2000 to 20-30 in 2002) but still exists. I don't want to "name ASes" <grin>. Does any one have any explanations? Are network operators "notified" of their new AS number well in advance of the actual receipt of that number on paper, for example? Any help is appreciated (and hopefully this occurence is of interest to nanog). Thanks, --marwan ps. If one wishes to refer to a cluster of members of nanog, are they referred to as "NANOs"? (Not to be confused with the salutation made famous by tv's Mork & Mindy, of course) :-) ******************************************************** "Theatre is not supposed to change the world, but it can show the world can change." --unnamed director ********************************************************