But, with the expanded space, there is an issue of how to transition to the larger numbers. This is a software problem as much as anything. Until all software understands the bigger numbers, people will want to continue using the 16-bit ones.
I had a shot at documenting this in the form of a presentation slide pack. Even if you continue to use a 16 bit ASN indefinitely things may need to change:
http://www.potaroo.net/presentations/2006-10-11-asns.pdf
Meanwhile, to encourage the migration to 4-byte ASNs, the RIRs have been developing a globally-coordinated policy for how to transition to 4-byte ASNs (hi Geoff!). The first step of that process, effective January 1, 2007, is to allow requestors to obtain 4-byte ASNs (if they specifically request them). But, in order for the RIRs to be able to offer them, IANA has to give them some. Hence, the IESG action mentioned in the note. See http://www.arin.net/policy/proposals/2005_9.html for more details.
and http://www.potaroo.net/ispcol/2005-08/as.html for a (much longer) look at the role of ASNs and the way in which expanded AS numbers are to be transitioned in from a technical perspective
regards, Geoff _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf