Iljitsch van Beijnum has recently published an update on IPv6 adoption: IPv6 takes one step forward, IPv4 two steps back in 2012.
The second page of his article mentions the economics of IPv6 deployment as reason for the slow deployment of IPv6.
Apparently, the economics of moving to IPv6 before we absolutely, positively had to without delay weren’t there. As with all technology, IPv6 gets better and cheaper over time. And just like with houses, people prefer waiting rather than buying when prices are dropping. To make matters worse, if you’re the only one adopting IPv6, this buys you very little.
And the pain of the shrinking IPv4 supplies versus the pain of having to upgrade equipment and software varies for different groups of Internet users.
All this means that organizations that are experiencing a lack of sufficient IPv4 addresses will have to address that problem in some other way: by having multiple users share a single IPv4 address through Network Address Translation (NAT).
This echos my thoughts on the matter when I wrote about them extensively in 2011. Use of IPv4 NAT as a substitute for moving to IPv6 was one of the concerns that I and others have raised which could delay or deter IPv6 adoption.
A positive note on IPv6 deployment since 2011: It does seem that IPv6 has been adopted permanently by a number of the large content providers, so at least one side of the transaction is there. Further deployment of IPv6, in my opinion, now depends on the large cable and broadband providers. Only when millions of those subscribers are converted to be IPv6 enabled will we see significant uptake in IPv6 traffic.
Lee Howard of Time Warner noted last year at the IETF 84 that just getting to 1% of current broadband subscribers is a significant effort. At NANOG 56, Lee also noted that the economics of IPv4 xfers vs. carrier-grade NAT vs. IPv6 aren’t as simple as they might seem.