PLANET CS-2001 User Manual
Page 89
78
The IPv6 prefix is the part of the address that indicates the bits that have
fixed values. If it happens not to be a multiple of four such as
21DA:D3:0:2F3B:2AA:FF:FE28:9C5A/59, then the third 16 bits (i.e., 2F3B)
have to be modified (to 2F20) to become a multiple of four.
IPv6 addresses are classified into three types:
Unicast address:
Link-local addresses: These addresses are used on a single link and
have the following format: FE80::InterfaceID. A link-local address is
used primarily at startup for address autoconfiguration. It is analogous
to IPv4’s RFC 3927 address (169.254.0.0/16).
Site-local addresses: These addresses are used on a single site and
have the following format: FEC0::SubnetID:InterfaceID. The site-local
addresses are used for addressing inside a site without the need for a
global prefix. They are analogous to IPv4's RFC1918 addresses
(10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16).
Global IPv6 unicast addresses: These addresses can be used across
the Internet and have the following format: 010 (FP, 3 bits) TLA ID (13
bits) Reserved (8 bits) NLA ID (24 bits) SLA ID (16 bits) InterfaceID
(64 bits).
Multicast address: An identifier for a set of interfaces (typically belonging
to different nodes). A packet sent to this address is delivered to all the
interfaces identified by the address. The multicast address types supersede
the IPv4 broadcast addresses. They are prefixed with FF (that is, the first
bits are 11111111) such as FF02::1 for all nodes address, FF02::2 for all
routers address, etc.
Anycast address: An identifier for a set of interfaces (typically belonging
to different nodes). A packet sent to this address is delivered to only one
interface identified by the address. This is the nearest interface as identified
by routing metrics.
Note：
1. Converting an Ethernet MAC address (00-AA-00-3F-2A-1C) to EUI-64 format:
FF-FE is inserted between the third and fourth bytes. This yields
00-AA-00-FF-FE-3F-2A-1C.
The U/L bit, which is the seventh bit in the first byte, is complemented. The first byte in
binary form is 00000000. When the seventh bit is complemented, it becomes 00000010
(0x02).