On 05/04/2011 12:21 PM, Mikael Abrahamsson wrote:
Currently, yes. Long-term, no. There are plenty of ISPs who do not filter on /24 IPv4 either, but a lot do. I expect in a few years that most will filter on /32 for PA space and /48 for PI space. The only reason it's not done today is that people haven't made it a priority because there are so few IPv6 routes.
Similar thing can be done on IPv4 these days. You can filter on PA minimal assignments to LIRs too - RIRs in general documents that and public examples of these filters are also available. But this expect, that you'll mantain this kind of filter - this is nothing like setup & forget. If network operators aren't filtering routing mess in IPv4 (even they can), they generally will not magically change their mind for IPv6. Filtering in IPv4 isn't happening, even you can reduce table by ~40% of prefixes - and this is not small number within >350000 IPv4 prefixes announced. Transit customers also expect this number on their peers, if you reduce your table in such manner, they'll complain to you, because your competitor will not filter and they expect similar number of prefixes on both their transit peers...
So advising subnetting /32 further and announcing them in the DFZ might work short-term, but you do it at your own risk long-term.
I'm not advising that. I'm just talking about something I already see in the global routing table. Deaggregation is a risk in both IPv4 and IPv6. Hohever, deaggregation works, in both worlds... And we cannot change minds of the operators by any policy. Keep in mind, that not so many comercial ISPs are involved in these policy discussions. They'll just setup their networks in accordance to customer needs, regardless of the policy made here. Daniel