User's Manual

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Users Manual of CS-6306R
Configuring RADIUS 6.2
This chapter describes the Remote Authentication Dial-In User Service (RADIUS) security system, defines its
operation, and identifies appropriate and inappropriate network environments for using RADIUS technology.
The "RADIUS Configuration Task List" section describes how to configure RADIUS with the authentication,
authorization, and accounting (AAA) command set.
6.2.1 Introduction
6.2.1.1 RADIUS Introduction
RADIUS is a distributed client/server system that secures networks against unauthorized access. In the
implementation, RADIUS clients run on switches and send authentication requests to a central RADIUS
server that contains all user authentication and network service access information.
RADIUS has been implemented in a variety of network environments that require high levels of security while
maintaining network access for remote users.
Use RADIUS in the following network environments that require access security: :
 Networks with multiple-vendor access servers, each supporting RADIUS. For example, access servers
from several vendors use a single RADIUS server-based security database. In an IP-based network with
multiple vendors' access servers, dial-in users are authenticated through a RADIUS server that has been
customized to work with the Kerberos security system.
 Networks in which a user must only access a single service. Using RADIUS, you can control user access
to a single host, to a single utility such as Telnet, or to a single protocol such as Point-to-Point Protocol
(PPP). For example, when a user logs in, RADIUS identifies this user as having authorization to run PPP
using IP address 10.2.3.4 and the defined access list is started.
 Networks that require resource accounting. You can use RADIUS accounting independent of RADIUS
authentication or authorization. The RADIUS accounting functions allow data to be sent at the start and
end of services, indicating the amount of resources (such as time, packets, bytes, and so on) used during
the session. An Internet service provider (ISP) might use a freeware-based version of RADIUS access
control and accounting software to meet special security and billing needs.
RADIUS is not suitable in the following network security situations:
 Multiprotocol access environments. RADIUS does not support the following protocols:
 AppleTalk Remote Access (ARA)
 NetBIOS Frame Control Protocol (NBFCP)
 NetWare Asynchronous Services Interface (NASI)
 X.25 PAD connections
 Switch-to-switch situations. RADIUS does not provide two-way authentication.
 Networks using a variety of services. RADIUS generally binds a user to one service model.