IPv6 Addressing Overview

IPv6 increases the number of network address bits from 32 (IPv4) to 128 bits, which provides more unique IP addresses to support more network devices.

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

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IPv6 address format

As shown in the figure, HHHH is a 16-bit hexadecimal value. H is a 4-bit hexadecimal value. The following is an example of an IPv6 address: 2001:0000:0000:0200:002D:D0FF:FE48:4672.

An IPv6 address can include hexadecimal fields of zeros. To make the address manageable, you can:

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

As shown in the figure, the IPv6 network prefix consists of the left-most bits of the address. As with an IPv4 address, you can specify the IPv6 prefix using the prefix/prefix-length format, for which the following rules apply.

The following is an example of an IPv6 prefix: 2001:DB8:49EA:D088::/64.