Kerberos operation – Dell POWEREDGE M1000E User Manual

Page 238

Advertising
background image

8-34

Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide

OL-13270-03

Chapter 8 Configuring Switch-Based Authentication

Controlling Switch Access with Kerberos

Kerberos Operation

A Kerberos server can be a switch that is configured as a network security server and that can
authenticate remote users by using the Kerberos protocol. Although you can customize Kerberos in a
number of ways, remote users attempting to access network services must pass through three layers of
security before they can access network services.

To authenticate to network services by using a switch as a Kerberos server, remote users must follow
these steps:

1.

Authenticating to a Boundary Switch, page 8-35

2.

Obtaining a TGT from a KDC, page 8-35

3.

Authenticating to Network Services, page 8-35

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 8-2

Kerberos Terms (continued)

Term

Definition

Advertising