User's Manual

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Cisco 3200 Series Wireless MIC Software Configuration Guide
OL-7734-02
Chapter 3 Administering the WMIC
Configuring and Enabling RADIUS
Note For complete syntax and usage information for the commands used in this section, refer to the Cisco IOS
Security Command Reference for Release 12.2.
Identifying the RADIUS Server Host
Access point-to-RADIUS-server communication involves several components:
• Host name or IP address
• Authentication destination port
• Accounting destination port
• Key string
• Timeout period
• Retransmission value
RADIUS security servers are identified by their host name or IP address, host name and specific UDP
port numbers, or IP address and specific UDP port numbers. The combination of the IP address and the
UDP port number creates a unique identifier allowing different ports to be individually defined as
RADIUS hosts providing a specific AAA service. This unique identifier enables RADIUS requests to be
sent to multiple UDP ports on a server at the same IP address.
If two different host entries on the same RADIUS server are configured for the same service—such as
accounting—the second host entry configured acts as a fail-over backup to the first one. Using this
example, if the first host entry fails to provide accounting services, the bridge tries the second host entry
configured on the same device for accounting services. (The RADIUS host entries are tried in the order
that they are configured.)
A RADIUS server and the bridge use a shared secret text string to encrypt passwords and exchange
responses. To configure RADIUS to use the AAA security commands, you must specify the host running
the RADIUS server daemon and a secret text (key) string that it shares with the bridge.
The timeout, retransmission, and encryption key values can be configured globally per server for all
RADIUS servers or in some combination of global and per-server settings. To apply these settings
globally to all RADIUS servers communicating with the bridge, use the three unique global
configuration commands: radius-server timeout, radius-server retransmit, and radius-server key. To
apply these values on a specific RADIUS server, use the radius-server host global configuration
command.
Note If you configure both global and per-server functions (timeout, retransmission, and key
commands) on the bridge, the per-server timer, retransmission, and key value commands
override global timer, retransmission, and key value commands. For information on
configuring these setting on all RADIUS servers, see the “Configuring Settings for All
RADIUS Servers” section on page 3-42.
You can configure the bridge to use AAA server groups to group existing server hosts for authentication.
For more information, see the “Defining AAA Server Groups” section on page 3-39.
Beginning in privileged EXEC mode, follow these steps to configure per-server RADIUS server
communication. This procedure is required.