Appendix F IPv6

Link-local Address

A link-local address uniquely identifies a device on the local network (the LAN). It is similar to a “private IP address” in IPv4. You can have the same link-local address on multiple interfaces on a device. A link-local unicast address has a predefined prefix of fe80::/10. The link-local unicast address format is as follows.

Table 158 Link-local Unicast Address Format

1111 1110 10

0

Interface ID

 

 

 

10 bits

54 bits

64 bits

 

 

 

Global Address

A global address uniquely identifies a device on the Internet. It is similar to a “public IP address” in IPv4. A global unicast address starts with a 2 or 3.

Unspecified Address

An unspecified address (0:0:0:0:0:0:0:0 or ::) is used as the source address when a device does not have its own address. It is similar to “0.0.0.0” in IPv4.

Loopback Address

A loopback address (0:0:0:0:0:0:0:1 or ::1) allows a host to send packets to itself. It is similar to “127.0.0.1” in IPv4.

Multicast Address

In IPv6, multicast addresses provide the same functionality as IPv4 broadcast addresses. Broadcasting is not supported in IPv6. A multicast address allows a host to send packets to all hosts in a multicast group.

Multicast scope allows you to determine the size of the multicast group. A multicast address has a predefined prefix of ff00::/8. The following table describes some of the predefined multicast addresses.

Table 159 Predefined Multicast Address

MULTICAST ADDRESS

DESCRIPTION

FF01:0:0:0:0:0:0:1

All hosts on a local node.

FF01:0:0:0:0:0:0:2

All routers on a local node.

FF02:0:0:0:0:0:0:1

All hosts on a local connected link.

FF02:0:0:0:0:0:0:2

All routers on a local connected link.

FF05:0:0:0:0:0:0:2

All routers on a local site.

FF05:0:0:0:0:0:1:3

All DHCP severs on a local site.

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P-2812HNU-51c User’s Guide