Ipv6 Address Format - IBM RackSwitch G8000 Application Manual

IPv6 Address Format

© Copyright IBM Corp. 2011
The IPv6 address is 128 bits (16 bytes) long and is represented as a sequence of
eight 16-bit hex values, separated by colons.
Each IPv6 address has two parts:
• Subnet prefix representing the network to which the interface is connected
• Local identifier, either derived from the MAC address or user-configured
The preferred hexadecimal format is as follows:
xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
Example IPv6 address:
FEDC:BA98:7654:BA98:FEDC:1234:ABCD:5412
Some addresses can contain long sequences of zeros. A single contiguous
sequence of zeros can be compressed to :: (two colons). For example, consider the
following IPv6 address:
FE80:0:0:0:2AA:FF:FA:4CA2
The address can be compressed as follows:
FE80::2AA:FF:FA:4CA2
Unlike IPv4, a subnet mask is not used for IPv6 addresses. IPv6 uses the subnet
prefix as the network identifier. The prefix is the part of the address that indicates the
bits that have fixed values or are the bits of the subnet prefix. An IPv6 prefix is
written in address/prefix-length notation. For example, in the following address, 64
is the network prefix:
21DA:D300:0000:2F3C::/64
IPv6 addresses can be either user-configured or automatically configured.
Automatically configured addresses always have a 64-bit subnet prefix and a 64-bit
interface identifier. In most implementations, the interface identifier is derived from
the switch's MAC address, using a method called EUI-64.
Most IBM N/OS 6.8 features permit IP addresses to be configured using either IPv4
or IPv6 address formats. Throughout this manual, IP address is used in places
where either an IPv4 or IPv6 address is allowed. In places where only one type of
address is allowed, the type (IPv4 or IPv6 is specified.
Chapter 16. Internet Protocol Version 6
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