No special VPN configuration is required. When a computer on the internal IPSec VPN network connects to
the internal network behind the Internet IPSec VPN gateway, the DFL-500 accepts IPSec VPN connections
from the internal network and performs network address translation on them. The VPN packets are forwarded
to the destination IPSec VPN gateway with a source address of the external interface of the DFL-500.
DFL-500 User Manual
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