D-Link 800 - DFL 800 - Security Appliance, User Manual

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• Set Remote Endpoint to remote_gw.
• Set Encapsulation mode to Tunnel.
• Choose the IKE and IPsec algorithm proposal lists to be used.
• For Authentication select the Pre-shared Key object defined in step (1) above.
The IPsec Tunnel object can be treated exactly like any NetDefendOS Interface object in later
steps.
5. Set up two IP rules in the IP rule set for the tunnel:
• An Allow rule for outbound traffic that has the previously defined ipsec_tunnel object as
the Destination Interface. The rule's Destination Network is the remote network
remote_net.
• An Allow rule for inbound traffic that has the previously defined ipsec_tunnel object as the
Source Interface. The Source Network is remote_net.
Action Src Interface Src Network Dest Interface Dest Network Service
Allow lan lannet ipsec_tunnel remote_net All
Allow ipsec_tunnel remote_net lan lannet All
The Service used in these rules is All but it could be a predefined service.
6. Define a new NetDefendOS Route which specifies that the VPN Tunnel ipsec_tunnel is the
Interface to use for routing packets bound for the remote network at the other end of the tunnel.
Interface Network Gateway
ipsec_tunnel remote_net <empty>
9.2.2. IPsec LAN to LAN with Certificates
LAN to LAN security is usually provided with pre-shared keys but sometimes it may be desirable to
use X.509 certificates instead. If this is the case, Certificate Authority (CA) signed certificates may
be used and these come from an internal CA server or from a commercial supplier of certificates.
Alternatively, self-signed certificates can be used and these can be generated from a number of
utilities downloadable from the Internet.
Creating a LAN to LAN tunnel with certificates follows exactly the same procedures as the previous
section except that certificates replace pre-shared keys for authentication.
Two certificates are required for a LAN to LAN tunnel and both should be signed by the same CA.
The same two are used at either end of an IPsec tunnel but their use is reversed at either end. In
other words: one certificate is used as the root certificate at one tunnel end, call it Side A, and as the
host certificate at the other end, call it Side B. The second certificate is used in the opposite way: it
is the host certificate at Side A and the root certificate at Side B.
The certificate setup steps are:
1. The NetDefendOS date and time must be set correctly since certificates can expire.
2. Open the WebUI management interface for the D-Link Firewall at one end of the tunnel.
3. Under Authentication Objects, add the Root Certificate and Host Certificate into
NetDefendOS. The root certificate needs to have 2 parts added: a certificate file and a private
9.2.2. IPsec LAN to LAN with
Certificates Chapter 9. VPN
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