Internet Protocol Version 6 (IPv6)

The Internet Engineer Task Force (IETF) defined IPv6 in 1995. While IPv4 still has the majority of addressing, all network operating systems and hardware device manufacturers support IPv6. IPv6 increases the size of IP addresses from 32 bits to 128 bits, or 16 octets. This increases the possible number of available addresses to a maximum of 2128, or 3.42×1038, unique addresses. With the large number of available IPv6 addresses, it is not necessary to implement addressing conservation methods such as NAT and CIDR. This will help reduce the administration overhead of managing addresses.

The IPv6 address is composed of hexadecimal digits representing 16-bit sections separated by a colon. The addresses are represented by the format xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx. An example of the preferred format for IPv6 addresses would look like the following:

  • 2130:0000:0000:0000:0003:0040:150c:235b

IPv6 may be abbreviated by removing the leading zeros from the address, so if applied to the previous example, the address could appear as follows:

  • 2130:0:0:0:3:40:150c:235b

Another shorthand version of the IPv6 address uses double-colon notation, wherein address sections that consist of a series of zeros may be replaced with a double colon. In the instance of the IPv6 address 2130:0000:0000:0000:0003:0040:150c:235b, it could be shortened to:

  • 2130::3:40:150c:235b

IPv6 address several disadvantages of IPv4 addressing, including:

Limited addresses

As mentioned previously, ...

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