Technologies being designed, developed and implemented for IoT make extensive use of IPv6. The reason is so obvious: IPv4 address space(1) cannot support the huge number of devices that will connect to the Internet(2). And techniques like NATtin are not trusted as a long-term solution(3).
However, the adoption of IPv6 is still lagging behind. The worldwide deployment was launched only on June 2012(4). And the largest end-to-end adoption led by the US and Germany doesn't exceed 15%(5).
- IPv4 allows around 4 billions user addresses while IPv6 allows almost limitless addresses, that is: 3.4×10^38
- Gartner Says 4.9 Billion Connected "Things" Will Be in Use in 2015and 25 billion connected devices by 2020 .
- IPv6 Readiness in the Communication Service Provider Industry, page 7
- IPv6 Is The New Normal
- World IPv6 Adoption