H3C S7500E Series Ethernet Switches Operation Manual

Operation Manual – IPv6 Configuration
H3C S7500E Series Ethernet Switches Chapter 1 IPv6 Basics Configuration
1-6
z Unassigned address: The unicast address "::” is called the unassigned address
and may not be assigned to any node. Before acquiring a valid IPv6 address, a
node may fill this address in the source address field of an IPv6 packet, but may
not use it as a destination IPv6 address.
IV. Multicast address
IPv6 multicast addresses listed in Table 1-2 are reserved for special purpose.
Table 1-2 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
Besides, there is another type of multicast address: solicited-node address. A
solicited-node multicast address is used to acquire the link-layer addresses of neighbor
nodes on the same link and is also used for duplicate address detection (DAD). Each
IPv6 unicast or anycast address has one corresponding solicited-node address. The
format of a solicited-node multicast address is as follows:
FF02:0:0:0:0:1:FFXX:XXXX
Where, FF02:0:0:0:0:1 FF is permanent and consists of 104 bits, and XX:XXXX is the
last 24 bits of an IPv6 unicast or anycast address.
V. Interface identifier in IEEE EUI-64 format
Interface identifiers in IPv6 unicast addresses are used to identify interfaces on a link
and they are required to be unique on that link. Interface identifiers in IPv6 unicast
addresses are currently required to be 64 bits long. An interface identifier in IEEE
EUI-64 format is derived from the link-layer address of that interface. Interface
identifiers in IPv6 addresses are 64 bits long, while MAC addresses are 48 bits long.
Therefore, the hexadecimal number FFFE needs to be inserted in the middle of MAC
addresses (behind the 24 high-order bits). To ensure the interface identifier obtained
from a MAC address is unique, it is necessary to set the universal/local (U/L) bit (the
seventh high-order bit) to “1”. Thus, an interface identifier in IEEE EUI-64 format is
obtained.