Blade ICE RACKSWITCH G8124-E - Manual (Page 232)

BLADEOS 6.5.2 Application Guide
232 Chapter 16: Internet Protocol Version 6 BMD00220, October 2010
IPv6 Address Types
IPv6 supports three types of addresses: unicast (one-to-one), multicast (one-to-many), and anycast
(one-to-nearest). Multicast addresses replace the use of broadcast addresses.
Unicast Address
Unicast is a communication between a single host and a single receiver. Packets sent to a unicast
address are delivered to the interface identified by that address. IPv6 defines the following types of
unicast address:
Global Unicast address: An address that can be reached and identified globally. Global Unicast
addresses use the high-order bit range up to FF00, therefore all non-multicast and
non-link-local addresses are considered to be global unicast. A manually configured IPv6
address must be fully specified. Autoconfigured IPv6 addresses are comprised of a prefix
combined with the 64-bit EUI. RFC 4291 defines the IPv6 addressing architecture.
The interface ID must be unique within the same subnet.
Link-local unicast address: An address used to communicate with a neighbor on the same link.
Link-local addresses use the format
FE80::EUI
Link-local addresses are designed to be used for addressing on a single link for purposes such
as automatic address configuration, neighbor discovery, or when no routers are present.
Routers must not forward any packets with link-local source or destination addresses to other
links.
Multicast
Multicast is communication between a single host and multiple receivers. Packets are sent to all
interfaces identified by that address. An interface may belong to any number of multicast groups.
A multicast address (FF00 - FFFF) is an identifier for a group interface. The multicast address most
often encountered is a solicited-node multicast address using prefix
FF02::1:FF00:0000/104
with the low-order 24 bits of the unicast or anycast address.
The following well-known multicast addresses are pre-defined. The group IDs defined in this
section are defined for explicit scope values, as follows:
FF00:::::::0 through FF0F:::::::0