Cisco Catalyst 3750-E Series, Software Configuration Manual

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Catalyst 3750-E and 3560-E Switch Software Configuration Guide
OL-9775-08
Chapter 9 Configuring Switch-Based Authentication
Controlling Switch Access with Kerberos
Instance An authorization level label for Kerberos principals. Most Kerberos
principals are of the form
user@REALM (for example,
smith@EXAMPLE.COM). A Kerberos principal with a Kerberos
instance has the form
user/instance@REALM (for example,
smith/admin@EXAMPLE.COM). The Kerberos instance can be used to
specify the authorization level for the user if authentication is successful.
The server of each network service might implement and enforce the
authorization mappings of Kerberos instances but is not required to do so.
Note The Kerberos principal and instance names must be in all
lowercase characters.
Note
The Kerberos realm name must be in all uppercase characters.
KDC
2
Key distribution center that consists of a Kerberos server and database
program that is running on a network host.
Kerberized A term that describes applications and services that have been modified
to support the Kerberos credential infrastructure.
Kerberos realm A domain consisting of users, hosts, and network services that are
registered to a Kerberos server. The Kerberos server is trusted to verify
the identity of a user or network service to another user or network
service.
Note The Kerberos realm name must be in all uppercase characters.
Kerberos server A daemon that is running on a network host. Users and network services
register their identity with the Kerberos server. Network services query
the Kerberos server to authenticate to other network services.
KEYTAB
3
A password that a network service shares with the KDC. In Kerberos 5
and later Kerberos versions, the network service authenticates an
encrypted service credential by using the KEYTAB to decrypt it. In
Kerberos versions earlier than Kerberos 5, KEYTAB is referred to as
SRVTAB
4
.
Principal Also known as a Kerberos identity, this is who you are or what a service
is according to the Kerberos server.
Note
The Kerberos principal name must be in all lowercase characters.
Service credential A credential for a network service. When issued from the KDC, this
credential is encrypted with the password shared by the network service
and the KDC. The password is also shared with the user TGT.
SRVTAB A password that a network service shares with the KDC. In Kerberos 5
or later Kerberos versions, SRVTAB is referred to as KEYTAB.
TGT Ticket granting ticket that is a credential that the KDC issues to
authenticated users. When users receive a TGT, they can authenticate to
network services within the Kerberos realm represented by the KDC.
1. TGT = ticket granting ticket
2. KDC = key distribution center
3. KEYTAB = key table
4. SRVTAB = server table
Table 9-5 Kerberos Terms (continued)
Term Definition