H3C Technologies H3C WX3000E Series Wireless Switches - Manual (Page 114)

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The type of an IPv6 address is designated by the first several bits, the format prefix. Table 6 lists the
mappings between address types and format prefixes.
Table 6 Mappings between address types and format prefixes
Type Format prefix (binary) IPv6 prefix ID
Unicast
address
Unspecified address 00...0 (128 bits) ::/128
Loopback address 00...1 (128 bits) ::1/128
Link-local address 1111111010 FE80::/10
Site-local address 1111111011 FEC0::/10
Global unicast address Other forms —
Multicast address 11111111 FF00::/8
Anycast address
Anycast addresses use the unicast address space and have the
identical structure of unicast addresses.
Unicast addresses
Unicast addresses comprise global unicast addresses, link-local unicast addresses, site-local unicast
addresses, the loopback address, and the unspecified address.
• Global unicast addresses, equivalent to public IPv4 addresses, are provided for network service
providers. This type of address allows efficient prefix aggregation to restrict the number of global
routing entries.
• Link-local addresses are used for communication among link-local nodes for neighbor discovery
and stateless autoconfiguration. Packets with link-local source or destination addresses are not
forwarded to other links.
• Site-local unicast addresses are similar to private IPv4 addresses. Packets with site-local source or
destination addresses are not forwarded out of the local site (or a private network).
• 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 7 are reserved for special purposes.
Table 7 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