Multicast addresses, Eui-64 address-based interface identifiers – H3C Technologies H3C SecPath F1000-E User Manual

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A loopback address is 0:0:0:0:0:0:0:1 (or ::1). It may never be assigned to any physical interface

and can be used by a node to send an IPv6 packet to itself in the same way as the loopback
address in IPv4.

An unspecified address is 0:0:0:0:0:0:0:0 (or ::). It cannot be assigned to any node. Before
acquiring a valid IPv6 address, a node fills this address in the source address field of IPv6 packets.

The unspecified address cannot be used as a destination IPv6 address.

Multicast addresses

IPv6 multicast addresses listed in

Table 83

are reserved for special purposes.

Table 83 Reserved IPv6 multicast addresses

Address Application

FF01::1

Node-local scope all-nodes multicast address

FF02::1

Link-local scope all-nodes multicast address

FF01::2

Node-local scope all-routers multicast address

FF02::2

Link-local scope all-routers multicast address

FF05::2

Site-local scope all-routers multicast address

Multicast addresses also include solicited-node addresses. A node uses a solicited-node multicast
address to acquire the link-layer address of a neighboring node on the same link and to detect duplicate

addresses. Each IPv6 unicast or anycast address has a corresponding solicited-node address. The format

of a solicited-node multicast address is FF02:0:0:0:0:1:FFXX:XXXX where FF02:0:0:0:0:1:FF is fixed and

consists of 104 bits, and XX:XXXX is the last 24 bits of an IPv6 unicast address or anycast address.

EUI-64 address-based interface identifiers

An interface identifier is 64 bits and uniquely identifies an interface on a link.
Interfaces generate EUI-64 address-based interface identifiers differently.

On an IEEE 802 interfaces (such as an Ethernet interface)
The interface identifier is derived from the link-layer address (typically a MAC address) of the
interface. To expand the 48-bit MAC address to a 64-bit interface identifier, the hexadecimal

number FFFE (16 bits of 1111111111111110) is inserted into the MAC address (behind the 24th

high-order bit). To make sure that the obtained interface identifier is globally unique, the
universal/local (U/L) bit (which is the seventh high-order bit) is set to 1. Thus, an EUI-64

address-based interface identifier is obtained.

Figure 354 Converting a MAC address into an EUI-64 address-based interface identifier

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