ZyXEL Communications ZYWALL USG 2000 Manual page 433

11 Select Use this string to protect the key exchange (preshared key), type
password in the text box, and click Next.
Figure 300 IP Security Policy Properties: Authentication Method
12 Click Add.
Figure 301 IP Security Policy Properties: IP Filter List
ZyWALL USG 2000 User's Guide
Chapter 27 L2TP VPN Example
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