Chapter 1 Overview of Cisco Secure ACS
AAA Server Functions and Concepts
1-6
User Guide for Cisco Secure ACS for Windows Server
78-14696-01, Version 3.1
AAA Protocols— and RADIUS
Cisco Secure ACS can use both the and RADIUS AAA protocols.
Table 1-1
compares the two protocols.
Cisco Secure ACS conforms to the protocol as defined by Cisco
Systems in draft 1.77. For more information, refer to the Cisco IOS software
documentation or Cisco.com (
http://www.cisco.com
).
RADIUS
Cisco Secure ACS conforms to the RADIUS protocol as defined in draft April
1997 and in the following Requests for Comments (RFCs):
•
RFC 2138, Remote Authentication Dial In User Service
•
RFC 2139, RADIUS Accounting
•
RFC 2865
Table 1-1
and RADIUS Protocol Comparison
Point of Comparison
RADIUS
Transmission Protocol TCP—connection-oriented transport
layer protocol, reliable full-duplex
data transmission
UDP—connectionless transport layer
protocol, datagram exchange without
acknowledgments or guaranteed
delivery
Ports Used
49
Authentication and Authorization:
1645 and 1812
Accounting: 1646 and 1813
Encryption
Full packet encryption
Encrypts only passwords up to 16
bytes
AAA Architecture
Separate control of each service:
authentication, authorization, and
accounting
Authentication and authorization
combined as one service
Intended Purpose
Device management
User access control