ZyXEL Communications 100 Series User Manual

ZyWALL USG 100/200 Series User’s Guide

You can use a AAA (Authentication, Authorization, Accounting) server to provide access 
control to your network. The AAA server can be a Active Directory, LDAP, or RADIUS 
server. Use the AAA Server screens to create and manage objects that contain settings for 
using individual AAA servers or groups of AAA servers. You use AAA server objects in 
configuring authentication method objects (see 

). 

LDAP/AD allows a client (the ZyWALL) to connect to a server to retrieve information from a 
directory. A network example is shown next. 

Figure 461   Example: Directory Service Client and Server 

The following describes the user authentication procedure via an LDAP/AD server. 

1 A user logs in with a user name and password pair. 
2 The ZyWALL tries to bind (or log in) to the LDAP/AD server. 
3 When the binding process is successful, the ZyWALL checks the user information in the 

directory against the user name and password pair. 

4 If it matches, the user is allowed access. Otherwise, access is blocked. 

RADIUS (Remote Authentication Dial-In User Service) authentication is a popular protocol 
used to authenticate users by means of an external server instead of (or in addition to) an 
internal device user database that is limited to the memory capacity of the device. In essence, 
RADIUS authentication allows you to validate a large number of users from a central location.