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Chapter 10 - Configuring VPN
ASUS SL1200
Figure 10.2. VPN Statistics Page
10.5 VPN Connection Examples
Gateways with integrated VPN and Firewall are useful in scenarios where:
• The traffic between branch offices is protected by VPN and
• Traffic destined for public Internet goes through Firewall/NAT.
To avoid NAT/IPSec interoperability issues, outgoing traffic is first
processed by Firewall/NAT and then by IPSec. Hence, you must ensure
that appropriate Firewall rules are configured to let the VPN traffic
gothrough. This section describes these scenarios and presents step-by-
step instructions for configuring these scenarios.
10.5.1 Intranet Scenario – fi VPN and no NAT for
VPN traffic
This is a common scenario where traffic to the public Internet goes through
the Firewall/NAT only and traffic between private networks is allowed
without NAT before IPSec processing. The same authority administers the
networks that are protected by VPN to avoid any possible address clash.
Configure each of the router for the Intranet scenario using the following
steps:
• Configure VPN connection rules.
• Configure Firewall access rules to allow inbound and outbound VPN
traffic.
• Configure a Firewall self rule to allow IKE packets into the router
