B-10
Cisco ASA 5500 Series Configuration Guide using the CLI
AppendixB Addresses, Protocols, and Ports
IPv6 Addresses
An anycast address cannot be assigned to an IPv6 host; it can only be assigned to an IPv6 router.
Note Anycast addresses are not supported on the ASA.

Required Addresses

IPv6 hosts must, at a minimum, be configured with the following addresses (either automatically or
manually):
A link-local address for each interface
The loopback address
The All-Nodes multicast addresses
A Solicited-Node multicast address for each unicast or anycast address
IPv6 routers must, at a minimum, be configured with the following addresses (either automatically or
manually):
The required host addresses
The Subnet-Router anycast addresses for all interfaces for which it is configured to act as a router
The All-Routers multicast addresses
IPv6 Address Prefixes
An IPv6 address prefix, in the format ipv6-prefix/prefix-length, can be used to represent bit-wise
contiguous blocks of the entire address space. The IPv6-prefix must be in the form documented in RFC
2373 where the address is specified in hexadecimal using 16-bit values between colons. The prefix
length is a decimal value that indicates how many of the high-order contiguous bits of the address
comprise the prefix (the network portion of the address). For example, 2001:0DB8:8086:6502::/32 is a
valid IPv6 prefix.
The IPv6 prefix identifies the type of IPv6 address. Table B- 5 shows the prefixes for each IPv6 address
type.
TableB-5 IPv6 Address Type Prefixes
Address Type Binary Prefix IPv6 Notation
Unspecified 000...0 (128 bits) ::/128
Loopback 000...1 (128 bits) ::1/128
Multicast 11111111 FF00::/8
Link-Local (unicast) 1111111010 FE80::/10
Site-Local (unicast) 1111111111 FEC0::/10
Global (unicast) All other addresses.
Anycast Taken from the unicast address space.