Le 27 nov. 2009 à 19:36, Mikael Abrahamsson a écrit :
On Fri, 27 Nov 2009, Rémi Després wrote:
No hard feelings, but I felt this needed to be said.
There is nothing wrong with 6RD in principle, it's when people map the entire IPv4 space into IPv6 blindly and then use a small fraction of it that it becomes wasteful.
Right (that's the use of 6rd which can create problems, not it's design or its implementation in gateways and home gateways).
I don't have a problem with ISPs will millions of subscribers getting a /24, I have a problem when "every" mom and pop ISP with an AS number is getting a /24 because they want to run 6RD.
As long as the policy incurs that you need to have a certain amount of customers to warrant running 6RD using all of IPv4 space and thus needing /24 or /28, otherwise you'd better map a smaller part of it and then you'll be able to fit it just fine into your /32 most likely.
/28 for any ISP having several IPv4 prefixes and committed to deploy 6rd would be IMHO a good choice. In practice, /60s to customer sites is quite sufficient, at least in the short term. (Note that mom and pop ISPs, presumably having each only one IPv4 prefix, would remain with /32s.) Then, going up to /24 for ISPs that deploy 6rd with at least 4 IPv4 prefixes, as you propose in another mail, would not be necessary, but could be a useful option. Regards, RD