ZyWALL 2WG Support Notes
All contents copyright (c) 2006 ZyXEL Communications Corporation. 110
NAT over IPSec on ZyNOS
Network Topology
The above is an IPSec VPN application running in tunnel mode. In the network topology shown, both the
local area networks (LAN) are assigned with the same network IP/network mask 172.168.1.0/24. Without
a special feature enchantment on both side gateway routers, establishing an IPSec VPN basing on this
network topology is not possible since it will cause a routing problem. You are required to manually