Required addresses, Ipv6 address prefixes, For inf – Cisco ASA 5505 User Manual

Page 1892

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B-10

Cisco ASA 5500 Series Configuration Guide using the CLI

Appendix B 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.

Table B-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.

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