Josh, The price of IPv4 addresses will go up now that supply is seriously constrained. The price increase will push information producers, who generally are the people needing public IPv4 space, over to IPv6, which is plentiful. This will create a class of services that is IPv6-only (e.g., Microsoft DirectAccess), which will encourage IPv4 information consumers to dual-stack. IPv4-only consumers will find themselves in an information ghetto, but one that they can easily get out of by just exerting a little effort. In the worst case scenario, an ISP customer stuck behind an IPv4 Internet connection can simply tunnel to IPv6 via one of the free tunnelbroker services such as HE.net<http://HE.net>’s tunnelbroker.net<http://tunnelbroker.net>.
This is a problem that will solve itself in a natural, and capitalist, way. Market pressures will push everyone to IPv6, and nobody need be left behind. I predict some enterprising inventor will create (if they haven’t already) a cheap IPv6 appliance akin to Roku or Apple TV that anyone can just drop onto their network to become IPv6 enabled via a tunnelbroker. In fact, I show just how to do this using a $99 Apple Airport Express in my three-hour online course “Build your own IPv6 Lab” (http://windowsitpro.com/build-your-own-ipv6-lab-and-become-ipv6-guru-demand). If you don’t have an IPv6 lab yet, you should set one up ASAP. That’s the easiest way to get your head around all IPv6 issues. HE.net<http://HE.net> also has a very nice certification program that will take you through all the basic tasks of being IPv6 enabled both as an information producer and a consumer. -mel On Jul 4, 2015, at 8:41 PM, John Levine <jo...@iecc.com<mailto:jo...@iecc.com>> wrote: In article <f78ee6a5-d4e5-435b-a6bf-bb6a84223...@atcnetworks.net<mailto:f78ee6a5-d4e5-435b-a6bf-bb6a84223...@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
