Cisco Systems 3560-X, 3750-X MAC Move, 802.1x Accounting, 802.1x Accounting Attribute-Value Pairs

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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 11 Configuring IEEE 802.1x Port-Based Authentication Understanding IEEE 802.1x Port-Based Authentication
MAC Move
When a MAC address is authenticated on one switch port, that address is not allowed on another 802.1x
port of the switch. If the switch detects that same MAC address on another 802.1x port, the address is
not allowed.
There are situations where a MAC address might need to move from one port to another on the same
switch. For example, when there is another device (for example a hub or an IP phone) between an
authenticated host and a switch port, you might want to disconnect the host from the device and connect
it directly to another port on the same switch.
You can globally enable MAC move so the device is reauthenticated on the new port. When a host moves
to a second port, the session on the first port is deleted, and the host is reauthenticated on the new port.
MAC move is supported on all host modes. (The authenticated host can move to any port on the switch,
no matter which host mode is enabled on the that port.)
Note MAC move is not supported on port-security enabled 802.1x ports. If MAC move is globally configured
on the switch and a port security-enabled host moves to an 802.1x-enabled port, a violation error occurs.
For more information see the “Enabling MAC Move” section on page 11-49.
802.1x Accounting
The 802.1x standard defines how users are authorized and authenticated for network access but does not
keep track of network usage. 802.1x accounting is disabled by default. You can enable 802.1x accounting
to monitor this activity on 802.1x-enabled ports:
• User successfully authenticates.
• User logs off.
• Link-down occurs.
• Re-authentication successfully occurs.
• Re-authentication fails.
The switch does not log 802.1x accounting information. Instead, it sends this information to the
RADIUS server, which must be configured to log accounting messages.
802.1x Accounting Attribute-Value Pairs
The information sent to the RADIUS server is represented in the form of Attribute-Value (AV) pairs.
These AV pairs provide data for different applications. (For example, a billing application might require
information that is in the Acct-Input-Octets or the Acct-Output-Octets attributes of a RADIUS packet.)
AV pairs are automatically sent by a switch that is configured for 802.1x accounting. Three types of
RADIUS accounting packets are sent by a switch:
• START–sent when a new user session starts
• INTERIM–sent during an existing session for updates
• STOP–sent when a session terminates