Vpn Deployment - D-Link DFL-1600 User Manual

20.3. Why VPN in Firewalls
In cases where the VPN gateway is located outside the firewall, can
the firewall recognize VPN protected traffic from plaintext Internet
traffic, so that it knows what to pass through to the internal network?
Does it require additional configuration to the firewall or hosts
participating in the VPN?
In D-Link firewalls, the Security Gateway VPN is integrated in the firewall
itself. The reasons for this design can be found in the scenario analysis
presented next.
20.3.1

VPN Deployment

Outside the Firewall, In-line
(Figure 20.1)
Figure 20.1: VPN Deployment Scenario 1
Benefits
Supports roaming clients, although it is difficult
No special routing information is needed in the firewall
The firewall can inspect and log plaintext from the VPN
Drawbacks
The Security Gateway is not protected by the firewall
The firewall cannot easily determine which traffic came through an
authenticated VPN and which came from the Internet, especially in
the case of roaming clients
Internet connectivity depends on the Security Gateway
D-Link Firewalls User's Guide
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