17. Li, X., Dawkins, S., Ward, D., and Durand, A. Softwire Problem Statement. RFC 4925, Internet Engineering Task Force, July 2007. 18. RIPE. IPv6 Address Allocation and Assignment Policy. PDF 552, RIPE, May 2012. 19. Mawatari, M., Kawashima, M., and Byrne, C. 464XLAT: Combination of Stateful and Stateless Transla- tion. Internet-Draft draft-ietf-v6ops-464xlat-09.txt, Internet Engineering Task Force, January 2013. Work in progress. 20. Bush, R. The Address plus Port (A+P) Approach to the IPv4 Address Shortage. RFC 6346, Internet Engi- neering Task Force, August 2011. 21. Troan, O., Dec, W., Li, X., Bao, C., Matsushima, S., and Murakami, T. Mapping of Address and Port with Encapsulation (MAP). Internet-Draft draft-ietf-softwire-map-02, Internet Engineering Task Force, Septem- ber 2012. Work in progress. 22. Soliman, H. Mobile IPv6 Support for Dual Stack Hosts and Routers. RFC 5555, Internet Engineering Task Force, June 2009. Deploying IPv6 in 3GPP Networks 23. 3GPP. Mobility management based on Dual-Stack Mobile IPv6; Stage. TS 24.303, 3rd Generation Partner- ship Project (3GPP), September 2011. 24. Carpenter, B. Advisory Guidelines for 6to4 Deployment. RFC 6343, Internet Engineering Task Force, August 2011. 25. Rekhter, Y., Moskowitz, B., Karrenberg, D., deGroot, G. J., and Lear, E. Address Allocation for Private Internets. RFC 1918, Internet Engineering Task Force, February 1996. 26. Bagnulo, M., Sullivan, A., Matthews, P., and vanBeijnum, I. DNS64: DNS Extensions for Network Address Translation from IPv6 Clients to IPv4 Servers. RFC 6147, Internet Engineering Task Force, April 2011. 27. Baker, F., Li, X., Bao, C., and Yin, K. Framework for IPv4/IPv6 Translation. RFC 6144, Internet Engi- neering Task Force, April 2011. 28. Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and Li, X. IPv6 Addressing of IPv4/IPv6 Translators. RFC 6052, Internet Engineering Task Force, October 2010. 29. Nordmark, E. Stateless IP/ICMP Translation Algorithm (SIIT). RFC 2765, Internet Engineering Task Force, February 2000. 30. Kawamur