ZyXEL Communications ZyWALL USG 1000 User Manual page 184

Chapter 8 L2TP VPN Example
10 Click Security, select Advanced (custom settings) and click Settings.
Figure 166 Connect L2TP to ZyWALL: Security
11 Select Optional encryption (connect even if no encryption) and the Allow
these protocols radio button. Select Unencrypted password (PAP) and clear
all of the other check boxes. Click OK.
Figure 167 Connect ZyWALL L2TP: Security > Advanced
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