What is IPv6?

IPv6 is short for "Internet Protocol Version 6". IPv6 is the "next generation" protocol designed by the IETF to replace the current version Internet Protocol, IP Version 4 ("IPv4").

Most of today's internet uses IPv4, which is now nearly twenty years old. IPv4 has been remarkably resilient in spite of its age, but it is beginning to have problems. Most importantly, there is a growing shortage of IPv4 addresses, which are needed by all new machines added to the Internet.

IPv6 fixes a number of problems in IPv4, such as the limited number of available IPv4 addresses. It also adds many improvements to IPv4 in areas such as routing and network autoconfiguration. IPv6 is expected to gradually replace IPv4, with the two coexisting for a number of years during a transition period.

IPv6 and DNS

Domain name system servers are the first physical devices that must make the transition to IPv6. This is a logical assumption because in order to have IPv6 address lookup, there must be an IPv6-compatible DNS server to answer the query.

IPv6 addresses are represented in the Domain Name System by AAAA records (so-called quad-A records) for forward lookups; reverse lookups take place under ip6.arpa

In July 2004, the Internet Corporation for Assigned Names and Numbers ("ICANN") announced that IPv6 addresses have been added to the Domain Names System (DNS) root zone, which paved the way for IPv6 deployment.