ZyXEL Communications 794M ユーザーズマニュアル

Prestige 794M User’s Guide

Chapter 7 VPN

82

Netmask

This field is applicable when you select Dial In in the Type field. 
Enter the subnet mask (in dotted decimal) notation to assign to the remote VPN 

client that initiates this VPN connection. For example, 255.255.255.0. 

Peer Network IP

Enter the IP address (in dotted decimal notation) of the remote network. For 

example, 192.168.1.1.

Username

If you select Dial Out in the Type field, enter the username provided. 
If you select Dial In in the Type field, enter a username to be used when 

establishing a VPN connection. 

Password

Enter the password associated with the username above. 

PPP 

Authentication 

Type

Specify the authentication type to use when accepting or establishing a VPN 

connection. Choices are PAP (Password Authentication Protocol) and CHAP 

(Challenge Handshake Authentication Protocol). The default is CHAP. 
When you select PAP, password is sent unencrypted. While CHAP provides better 

security by encrypting the password before transmission and reauthenticates the 

VPN client to protect against identity theft. 

Data Encryption

You can set the Prestige to encrypt data sent over the VPN connection using 

MPPE (Microsoft Point to Point Encryption). 
Select Auto to set the Prestige to automatically detect whether the remote VPN 

device uses data encryption. 
Select Enable to activate data encryption on the Prestige. Make sure the remote 

VPN device also has data encryption activated with the same encryption settings 

as the Prestige. 
Select Disable to deactivate data encryption on the Prestige. You cannot establish 

a VPN connection if data encryption in enabled on the remote VPN device. 

Key Length

Specify the key length for data encryption. Choices are Auto, 40 bits and 128 

bits. 
Select Auto to set the Prestige to automatically detect the key length used by the 

remote VPN device. 
Otherwise select 40 bits or 128 bits (for stronger encryption) to set the key length 

manually. 

Note: Make sure the key length is the same on the Prestige and the 

remote VPN device. 

Mode

Specify the encryption mode. Choices are Stateful and Stateless. 
Select Stateful to use a different encryption key after 256 packets of data 

transmitted. 
Select Stateless to use a different encryption key for each packet. 

Idle Time

Specify the time interval in minutes (where there is no traffic between the Prestige 

and the computer) that can elapse before the Prestige automatically disconnects 

the connection. 
Enter 0 to allow connection up all the time. 

Apply

Click Apply to save the changes. 

Table 42   VPN PPTP: LAN to LAN Connection (continued)