Some of the carriers who have gone IPv6-only like T-Mobile USA use technologies like 464XLAT to access IPv4 sites. Here's some info: http://www.internetsociety

Some of the carriers who have gone IPv6-only like T-Mobile USA use technologies like 464XLAT to access IPv4 sites. Here's some info: http://www.internetsociety.org/deploy360/resources/case-study-t-mobile-us-goes-ipv6-only-using-464xlat/ http://www.internetsociety.org/deploy360/resources/case-stud... And RFC 6877 specifies 464XLAT: http://tools.ietf.org/html/rfc6877 http://tools.ietf.org/html/rfc6877 and here is even more detailed info from T-Mobile: https://sites.google.com/site/tmoipv6/464xlat https://sites.google.com/site/tmoipv6/464xlat Regarding DS-Lite, this video from RIPE NCC provides a nice overview: http://www.ripe.net/lir-services/training/e-learning/ipv6/transition-mechanisms/ds-lite http://www.ripe.net/lir-services/training/e-learning/ipv6/tr... Both DS-Lite and 464XLAT are ways that an ISP can be IPv6-only yet still access legacy IPv4 content and services.