ZyXEL Communications 70 Series User Manual

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ZyWALL 5/35/70 Series User’s Guide
Appendix K VPN Setup
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P P E N D I X
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VPN Setup 
This appendix will help you to quickly create a IPSec/VPN connection between two ZyXEL 
IPSec routers. It should be considered a quick reference for experienced users.
General Notes
• The private networks behind the IPSec routers must be on different subnets. 
 
For example, 192.168.10.0/24 and 192.168.20.0/24.
• If the sites are/were previously connected using a leased line or ISDN router, physically 
disconnect these devices from the network before testing your new VPN connection. The 
old route may have been learnt by RIP and would take priority over the new VPN 
connection.
• To test whether or not a tunnel is working, ping from a computer at one site to a computer 
at the other. 
 
Before doing so, ensure that both computers have Internet access (via the IPSec routers).
• You can use the “E-MAIL” Peer Type and the “SUBNET” Local and Remote Address 
Type to simplify the configuration.
• Do not manually create any static IP routes for the remote VPN site. They are not 
required.
Dynamic IPSec Rule
Create a dynamic rule by setting the Remote Gateway Address to ‘0.0.0.0’. A single dynamic 
rule can support multiple simultaneous incoming IPSec connections.
All users of a dynamic rule have the same pre-shared key. You may need to change the pre-
shared key if one of the users leaves. See the support notes at http://www.zyxel.com for 
configuration examples for software VPN clients.
Full Feature NAT Mode
With Full Feature NAT mode, you must map the intended VPN rule’s local policy addresses 
as the Inside Local Address (ILA) to a public IP address assigned by the ISP (an Inside Global 
Address or IGA) before you can configure the VPN rule. For example, you could create a 
One-to-One address mapping rule that maps the VPN rule’s local policy addresses as the ILA 
to the VPN rule’s my IP address as the IGA. 
You may have to specify the public IP address in the My ZyWALL field of the local IPSec 
rule. If you have not configured the address mapping properly, a “SPD doesn’t match 
configuration of NAT” message displays when you try to save the IPSec rule.