Security Type Descriptions

Security Type Descriptions

Introduction

This section describes the types of security that the access server supports.

Kerberos

Kerberos is a user authentication system designed for open network computing environments. It provides for the authentication of a user name and password pair, by means of a host system accessible over the network. Once the user name and password pair is verified, the access server assigns any default authorization that identify the access server services allowed for that user’s session.

Realm Definition

Associated with a Kerberos login, a user specifies a realm. A realm is known by its realm name, a printable string of characters. The realm name identifies an administrative domain, and a set of realm parameters that are needed to administrate the logins for that realm. The administrator can also associate many other access server related parameters with a realm name.

The SHOW KERBEROS REALM realm-namecommand displays all the assignable parameters for all Kerberos realms. Realm definition and usage is the same for all other security methods supported by the access server, as are the characteristics that realms allow the administrator to define.

RADIUS

RADIUS (Remote Authentication Dial-In User Service) is a security method that provides authorization information during the authentication procedure. Authorization information is a means for tailoring most of the configurable features of the access server to a particular user name. The authorization characteristics are not stored on the access server, but are embedded in the database that exists on the security host serving as the RADIUS authenticator. This chapter describes the RADIUS authorization attributes that the access server supports. See the Managing RADIUS section in this chapter.

RADIUS Authorization

When a user attempts to log in using a realm, the user enters a string in the following format:

user-name@realm-name

22-2 Managing Access Server Security