The L2Tp Vpn Screen; L2Tp Setup - Server - ZyXEL Communications SBG5500 Series User Manual

a. The client has no activity for a period of time.
b. The client loses connectivity to the SBG for a period of time.
c. PPTP VPN is disabled on the SBG.
d. When any one of these configuration changes is applied on the SBG: WAN interface used for PPTP
VPN, IP address pool, access group.
e. The SBG's WAN interface on which the PPTP connection is established is disconnected.
A PPTP client is connected successfully but cannot access the local host or server behind the SBG.
3
Tip: This may be caused by one of the followings:
a. The local host or server is disconnected.
b. The access group is not configured correctly. From the SBG's GUI, go to VPN > PPTP VPN to check.
Note that all local hosts are by default accessible unless access group is configured.
c. IP Address Pool for PPTP VPN conflicts with any WAN, LAN, DMZ, WLAN, or L2TP VPN subnet configured
on the SBG. Note that the IP Address Pool for PPTP VPN has a 24-bit netmask and should not conflict with
any others listed above even if they are not in use.
A PPTP client is connected successfully but cannot browse the Internet.
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Tip: From the SBG's GUI, click VPN > PPTP VPN. Check if DNS Server is configured. A client cannot browse
the Internet without DNS resolved. Note that when a new DNS server is configured, the client must
disconnect then reconnect in order for the new DNS Server to take effect.
An Android device cannot connect to the SBG's PPTP VPN.
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Tip: Devices running an Android OS older than version 4.1 have issues with PPTP/MPPE encryption. Avoid
using devices that run an Android OS older than version 4.1 for PPTP VPN connection.

10.7 The L2TP VPN Screen

Click Configuration > VPN > L2TP VPN to open the following screen. Use this screen to configure the SBG
L2TP VPN settings.

10.7.1 L2TP Setup - Server

This screen displays when you select Server in the Type field.
Chapter 10 VPN
SBG5500/3310 Series User's Guide
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