1-7
Cisco ASA Series CLI Configuration Guide
Appendix 1 Addresses, Protocols, and Ports
IPv6 Addresses
Global Address
The general format of an IPv6 global unicast address is a global routing prefix followed by a subnet ID
followed by an interface ID. The global routing prefix can be any prefix not reserved by another IPv6
address type (see the
“IPv6 Address Prefixes” section on page 1-10
, for information about the IPv6
address type prefixes).
All global unicast addresses, other than those that start with binary 000, have a 64-bit interface ID in the
Modified EUI-64 format. See the
“Interface Identifiers” section on page 1-8
, for more information about
the Modified EUI-64 format for interface identifiers.
Global unicast address that start with the binary 000 do not have any constraints on the size or structure
of the interface ID portion of the address. One example of this type of address is an IPv6 address with
an embedded IPv4 address (see the
“IPv4-Compatible IPv6 Addresses” section on page 1-7
Site-Local Address
Site-local addresses are used for addressing within a site. They can be used to address an entire site
without using a globally unique prefix. Site-local addresses have the prefix FEC0::/10, followed by a
54-bit subnet ID, and end with a 64-bit interface ID in the modified EUI-64 format.
Site-local routers do not forward any packets that have a site-local address for a source or destination
outside of the site. Therefore, site-local addresses can be considered private addresses.
Link-Local Address
All interfaces are required to have at least one link-local address. You can configure multiple IPv6
addresses per interfaces, but only one link-local address.
A link-local address is an IPv6 unicast address that can be automatically configured on any interface
using the link-local prefix FE80::/10 and the interface identifier in modified EUI-64 format. Link-local
addresses are used in the neighbor discovery protocol and the stateless autoconfiguration process. Nodes
with a link-local address can communicate; they do not need a site-local or globally unique address to
communicate.
Routers do not forward any packets that have a link-local address for a source or destination. Therefore,
link-local addresses can be considered private addresses.
IPv4-Compatible IPv6 Addresses
There are two types of IPv6 addresses that can contain IPv4 addresses.
The first type is the IPv4-compatibly IPv6 address. The IPv6 transition mechanisms include a technique
for hosts and routers to dynamically tunnel IPv6 packets over IPv4 routing infrastructure. IPv6 nodes
that use this technique are assigned special IPv6 unicast addresses that carry a global IPv4 address in the
low-order 32 bits. This type of address is termed an IPv4-compatible IPv6 address and has the format
::y.y.y.y, where y.y.y.y is an IPv4 unicast address.
Note
The IPv4 address used in the IPv4-compatible IPv6 address must be a globally unique IPv4 unicast
address.
The second type of IPv6 address, which holds an embedded IPv4 address, is called the IPv4-mapped
IPv6 address. This address type is used to represent the addresses of IPv4 nodes as IPv6 addresses. This
type of address has the format ::FFFF:y.y.y.y, where y.y.y.y is an IPv4 unicast address.
Summary of Contents for 5505 - ASA Firewall Edition Bundle
Page 28: ...Glossary GL 24 Cisco ASA Series CLI Configuration Guide ...
Page 61: ...P A R T 1 Getting Started with the ASA ...
Page 62: ......
Page 219: ...P A R T 2 Configuring High Availability and Scalability ...
Page 220: ......
Page 403: ...P A R T 2 Configuring Interfaces ...
Page 404: ......
Page 499: ...P A R T 2 Configuring Basic Settings ...
Page 500: ......
Page 533: ...P A R T 2 Configuring Objects and Access Lists ...
Page 534: ......
Page 601: ...P A R T 2 Configuring IP Routing ...
Page 602: ......
Page 745: ...P A R T 2 Configuring Network Address Translation ...
Page 746: ......
Page 845: ...P A R T 2 Configuring AAA Servers and the Local Database ...
Page 846: ......
Page 981: ...P A R T 2 Configuring Access Control ...
Page 982: ......
Page 1061: ...P A R T 2 Configuring Service Policies Using the Modular Policy Framework ...
Page 1062: ......
Page 1093: ...P A R T 2 Configuring Application Inspection ...
Page 1094: ......
Page 1191: ...P A R T 2 Configuring Unified Communications ...
Page 1192: ......
Page 1333: ...P A R T 2 Configuring Connection Settings and QoS ...
Page 1334: ......
Page 1379: ...P A R T 2 Configuring Advanced Network Protection ...
Page 1380: ......
Page 1475: ...P A R T 2 Configuring Modules ...
Page 1476: ......
Page 1549: ...P A R T 2 Configuring VPN ...
Page 1550: ......
Page 1965: ...P A R T 2 Configuring Logging SNMP and Smart Call Home ...
Page 1966: ......
Page 2059: ...P A R T 2 System Administration ...
Page 2060: ......
Page 2098: ...1 8 Cisco ASA Series CLI Configuration Guide Chapter 1 Troubleshooting Viewing the Coredump ...
Page 2099: ...P A R T 2 Reference ...
Page 2100: ......