Ipsec Roaming Clients With Pre-Shared Keys - D-Link DFL-1660 User Manual

9.2.3. IPsec Roaming Clients with
Pre-shared Keys
Also review Section 9.7, "CA Server Access" below, which describes important considerations for
certificate validation.
Self-signed certificates instead of CA signed can be used for LAN to LAN tunnels but the Web
Interface and other interfaces do not have a feature to generate them. Instead, they must be
generated by another utility and imported into NetDefendOS. This means that they are not truly
self-signed since they are generated outside of NetDefendOS control and it should be remembered
that there is no guarantee that their private key is unique. However, the security provided can still be
considered adequate for some scenarios.
Two self-signed certificates are required and the same two are used at either end of the tunnel but
their usage is reversed. In other words: one certificate is used as the root certificate at one 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: as the host certificate at Side A and the root certificate at Side B.
No CA server considerations are needed with self-signed certificates since CRL lookup does not
occur.

9.2.3. IPsec Roaming Clients with Pre-shared Keys

This section details the setup with roaming clients connecting through an IPsec tunnel using
pre-shared keys to a protected Local Network which is located behind a NetDefend Firewall.
There are two types of roaming clients:
A. the IPv4 addresses of the clients are already allocated.
B. the IPv4 addresses of clients are not known beforehand and must be handed out by NetDefendOS
when the clients try to connect.
A. IP addresses already allocated
the IPv4 addresses may be known beforehand and have been pre-allocated to the roaming clients
before they connect. The client's IP address will be manually input into the VPN client software.
1. Set up user authentication. XAuth user authentication is not required with IPsec roaming clients
but is recommended (this step could initially be left out to simplify setup). The authentication
source can be one of the following:
• A Local User DB object which is internal to NetDefendOS.
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Chapter 9. VPN