Cisco Systems IE 2000 Local Authentication and Authorization

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Cisco IE 2000 Switch Software Configuration Guide
OL-25866-01
Chapter 12 Configuring Switch-Based Authentication
Information About Configuring Switch-Based Authentication
4. The KDC sends an encrypted TGT that includes the user identity to the switch.
5. The switch attempts to decrypt the TGT by using the password that the user entered.
• If the decryption is successful, the user is authenticated to the switch.
• If the decryption is not successful, the user repeats Step 2 either by reentering the username and
password (noting if Caps Lock or Num Lock is on or off) or by entering a different username
and password.
A remote user who initiates a un-Kerberized Telnet session and authenticates to a boundary switch is
inside the firewall, but the user must still authenticate directly to the KDC before getting access to the
network services. The user must authenticate to the KDC because the TGT that the KDC issues is stored
on the switch and cannot be used for additional authentication until the user logs on to the switch.
Obtaining a TGT from a KDC
This section describes the second layer of security through which a remote user must pass. T he user must
now authenticate to a KDC and obtain a TGT from the KDC to access network services.
Authenticating to Network Services
This section describes the third layer of security through which a remote user must pass. The user with
a TGT must now authenticate to the network services in a Kerberos realm.
Kerberos Configuration
So that remote users can authenticate to network services, you must configure the hosts and the KDC in
the Kerberos realm to communicate and mutually authenticate users and network services. To do this,
you must identify them to each other. You add entries for the hosts to the Kerberos database on the KDC
and add KEYTAB files generated by the KDC to all hosts in the Kerberos realm. You also create entries
for the users in the KDC database.
When you add or create entries for the hosts and users, follow these guidelines:
• The Kerberos principal name must be in all lowercase character s.
• The Kerberos instance name must be in all lowercase characters.
• The Kerberos realm name must be in all uppercase character s.
Note A Kerberos server can be a switch that is configured as a netwo rk security server and that can
authenticate users by using the Kerberos protocol.
To set up a Kerberos-authenticated server-client system, follow these steps:
• Configure the KDC by using Kerberos commands.
• Configure the switch to use the Kerberos protocol.
Local Authentication and Authorization
You can configure AAA to operate without a server by setting the switch to implement AAA in local
mode. The switch then handles authentication and authorization. No accounting is available in this
configuration.