IPv6 was designed to replace IPv4, the Internet protocol that is most commonly used currently
throughout the world. IPv6 increases the number of network address bits from 32 (IPv4) to 128
bits, which provides more than enough unique IP addresses to support all of the network devices
on the planet into the future. IPv6 is expected to quickly become the network standard.

An IPv6 address is composed of 8 fields of 16-bit hexadecimal values separated by colons (:).

Figure 1

shows the IPv6 address format.

FIGURE 1

IPv6 address format

As shown in

Figure 1

, HHHH is a 16-bit hexadecimal value, while H is a 4-bit hexadecimal value.

The following is an example of an IPv6 address.

2001:0000:0000:0200:002D:D0FF:FE48:4672

Note that this IPv6 address includes hexadecimal fields of zeros. To make the address less
cumbersome, you can do the following:

•

Omit the leading zeros; for example, 2001:0:0:200:2D:D0FF:FE48:4672.

•

Compress the successive groups of zeros at the beginning, middle, or end of an IPv6 address
to two colons (::) once per address; for example, 2001::200:2D:D0FF:FE48:4672.

When specifying an IPv6 address in a command syntax, keep the following in mind:

Network Prefix

Interface ID

HHHH = Hex Value 0000 – FFFF

128 Bits

HHHH