Cisco Systems Servers Manuale Utente

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Cisco Secure ACS 3.0 for Windows 2000/NT Servers User Guide
78-13751-01, Version 3.0
Chapter 4      Setting Up and Managing Network Configuration
About Distributed Systems
CiscoSecure database replication
Remote and centralized logging
AAA Servers in Distributed Systems
“AAA server” is the generic term for an access control server (ACS), and the two 
terms are often used interchangeably. AAA servers are used to determine who can 
access the network and what services are authorized for each user. The 
AAA server stores a profile containing authentication and authorization 
information for each user. Authentication information validates user identity, and 
authorization information determines what network services a user is permitted to 
use. A single AAA server can provide concurrent AAA services to many dial-up 
access servers, routers, and firewalls. Each network device can be configured to 
communicate with a AAA server. This makes it possible to centrally control 
dial-up access, as well as to secure network devices from unauthorized access.
These types of access control have unique authentication and authorization 
requirements. With Cisco Secure ACS, system administrators can use a variety of 
authentication methods that are used with different degrees of authorization 
privileges. 
Completing the AAA functionality, Cisco Secure ACS serves as a central 
repository for accounting information. Each user session granted by 
Cisco Secure ACS can be fully accounted for, and its accounting information can 
be stored in the server. This accounting information can be used for billing, 
capacity planning, and security audits.
Note
If the fields mentioned in this section do not appear in your Cisco Secure ACS 
HTML interface, enable them by clicking Interface Configuration, clicking 
Advanced Options, and then selecting the Distributed System Settings 
check box.
Default Distributed System Settings
You use both the AAA Servers table and the Proxy Distribution Table to establish 
distributed system settings. The parameters configured within these tables create 
the foundation to enable multiple Cisco Secure ACS servers to be configured to