Chapter 3 Authentication for FortiOS 5.0 : Single Sign-On to Windows AD
  
Single Sign-On to Windows AD
The FortiGate unit can authenticate users transparently and allow them network access based on their privileges in Windows AD. This means that users who have logged on to the network are not asked again for their credentials to access network resources through the FortiGate unit, hence the term “Single Sign-On”.
The following topics are included:
Introduction to Single Sign-On with Windows AD
Configuring Single Sign On to Windows AD
FortiOS FSSO log messages
Testing FSSO
Troubleshooting FSSO