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Chapter 2      Deploying Cisco Secure ACS
Basic Deployment Factors for Cisco Secure ACS
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Cisco Secure ACS 3.0 for Windows 2000/NT Servers User Guide
78-13751-01, Version 3.0
Cisco Secure ACS remote access policy provides control by using central 
authentication and authorization of remote users. The CiscoSecure user database 
maintains all user IDs, passwords, and privileges. Cisco Secure ACS access 
policies can be downloaded in the form of ACLs to network access servers such 
as the Cisco AS5300 Network Access Server, or by allowing access during 
specific periods, or on specific access servers.
The remote access policy is part of the overall corporate security policy.
Security Policy
We recommend that every organization that maintains a network develop a 
security policy for the organization. The sophistication, nature, and scope of your 
security policy directly affect how you deploy Cisco Secure ACS.
For more information about developing and maintaining a comprehensive 
security policy, refer to the following documents:
Network Security Policy: Best Practices White Paper
Delivering End-to-End Security in Policy-Based Networks
Cisco IOS Security Configuration Guide
Administrative Access Policy
Managing a network is a matter of scale. Providing a policy for administrative 
access to network devices depends directly on the size of the network and the 
number of administrators required to maintain the network. Local authentication 
on a network device can be performed, but it is not scalable. The use of network 
management tools can help in large networks, but if local authentication is used 
on each network device, the policy usually consists of a single login on the 
network device. This does not promote adequate network device security. Using 
Cisco Secure ACS allows a centralized administrator database, and 
administrators can be added or deleted at one location. TACACS+ is the 
recommended AAA protocol for controlling AAA client administrative access 
because of its ability to provide per-command control (command authorization) 
of a AAA client administrator’s access to the device. RADIUS is not well-suited 
for this purpose because of the one-time transfer of authorization information at 
time of initial authentication.