ZyXEL Communications USG40 User Manual page 459

Chapter 20 Web Authentication
Right-click the SSO icon and select Configure ZyXEL SSO Agent.
Configure the Agent Listening Port, AD server exactly as you have done on the ZyWALL/USG.
Add the ZyWALL/USG IP address as the Gateway. Make sure the ZyWALL/USG and SSO agent are
able to communicate with each other.
ZyWALL/USG Series User's Guide
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