In article <F78EE6A5-D4E5-435B-A6BF-BB6A84223415@atcnetworks.net> you write:
But what is the "best compromise" strategy? Dual stack + CGN? Some kind of intelligent 6to4 NAT?
Depends on the application(s). One that seems to work OK is to dual stack everyone and put them behind a NAT unless they ask to have a private IP. Depending on who your customers are, charge more for a private IP, or if you want to look less obviously venal, say you're offering a discount to customers who move their applications that require end-to-end addressing to IPv6. It is my strong impression that people who think they're 100% IPv6 enabled still often need a little IPv4 (NAT OK) for bootstrapping and the like, so you need to dual stack no matter what you do. If you do charge extra for IPv4, that makes it easier to go buy used IPv4 space on the aftermarket. R's, John