Hi, as announced to the RIPE routing working group mailing list [1] and elsewhere, over the next few days the Computer Networks research group at Roma Tre University, in collaboration with the RIPE NCC RIS project, will be performing experiments involving announcements with large AS-sets in the AS-path. We are doing this to test innovative network discovery methodologies we developed to allow ISPs to determine how their prefixes are seen by the rest of the Internet. The announcements will be for prefixes 84.205.73.0/24 and 84.205.89.0/24 and will originate in AS12654. We have been performing similar experiments over IPv6, in collaboration with the NAMEX internet exchange, since December 2004 with no ill effects; furthermore, our announcements are standard BGP, so conformant implementations should be able to process them, and very long AS-sets have already been observed in the past (e.g. [2], [3]). However, we want to be careful to avoid router bugs on legacy devices, old firmware versions and the like, so we are first sending out test announcements with progressively longer AS-sets. Should you encounter a problem with these advertisements, please let us know and we will withdraw them. The proposed timetable of the test announcements is as follows. 2005-03-04: 14:00 UTC: 10-element AS-set 14:30 UTC: withdrawal 16:00 UTC: 25-element AS-set 16:30 UTC: withdrawal and, if there are no problems: 2005-03-07: 14:00 UTC: 50-element AS-set 14:30 UTC: withdrawal 16:00 UTC: 100-element AS-set 16:30 UTC: withdrawal Note: For reference, the AS-sets already observed in [2] and [3] contained 123 and 124 ASes respectively. For questions/comments, please contact compunet@dia.uniroma3.it or lorenzo@ripe.net. Regards, Lorenzo Colitti On behalf of the Roma Tre Computer Networks Research group [1] http://www.ripe.net/ripe/maillists/archives/routing-wg/2005/msg00021.html [2] http://www.ripe.net/projects/ris/Talks/0101_RIPE38_AA/sld003.html [3] http://www.ripe.net/maillists/ncc-archives/ris-users/2002/msg00044.html