IPv6
Every device on the Internet is assigned an IP address for identification and location definition. It is like the "phone number" of your computer or network on the Internet. Defense Advanced Research Projects Agency (DARPA), a United States Department of Defense agency, came up with the original system known as IPv4 which has an addressing system that used numerical identifiers consisting of only 32 bits. IPv4 provides an addressing capability of 4.3 billion addresses. With the rapid growth of the Internet after commercialization in the 1990s, it became evident that far more addresses were necessary to connect new devices in the future.
Internet Protocol version 6 (IPv6) is the system devised to provide more addresses and is to eventually replace IPv4. IPv6 uses a 128-bit address, allowing more than 3.4x1038 addresses. IPv6 addresses are represented as eight groups of four hexadecimal digits separated by colons.
Example IPv4 Address:
192.168.1.1
Examples IPv6 Address:
2001:ccba::3257:9652 22:00:0a:a7:0f:7c
The long form of the IPv6 address:
fe80:0000:0000:0000:2000:0aff:fea7:0f7c
Is shortened to:
fe80::2000:0aff:fea7:0f7c
And is the Same Value.
IPv4 addresses use a dotted-decimal format, where each byte ranges from 0 to 255. IPv6 addresses use eight sets of four hexadecimal addresses (16 bits in each set), separated by a colon (:). A leading zero in a set of numbers can be omitted. Successive fields of zeroes in an IPv6 address, can be represented as two colons (::). A set of two colons (::) can only occur once in the IPv6 shorthand. An unspecified address is represented as ::, since it contains all zeroes.
The IPv6 Address:
fc40:0:0:0:200:f8ff:fe23:67cf
can be written as:
fc40::200:f8ff:fe23:67cf
The system is not backwards compatible. When the Internet is switched to Ipv6 it is best that everything online is switched in close time proximity. IPv6 does not specify interoperability features with IPv4, but essentially creates a parallel, independent network. Exchanging traffic between the two networks requires translator gateways employing one of several transition mechanisms, such as NAT64, or a tunneling protocol like 6to4, 6in4, or Teredo.
See also: 6T04 Adapter
