NETGEAR ProSafe FVS124G - Manual (Page 221)

Reference Manual for the ProSafe VPN Firewall 25 with 4 Gigabit LAN and Dual WAN Ports
Virtual Private Networking D-7
202-10085-01, March 2005
VPN Process Overview
Even though IPSec is standards-based, each vendor has its own set of terms and procedures for
implementing the standard. Because of these differences, it may be a good idea to review some of
the terms and the generic processes for connecting two gateways before diving into to the
specifics.
Network Interfaces and Addresses
The VPN gateway is aptly named because it functions as a “gatekeeper” for each of the computers
connected on the Local Area Network behind it.
In most cases, each Gateway will have a “public” facing address (WAN side) and a “private”
facing address (LAN side). These addresses are referred to as the “network interface” in
documentation regarding the construction of VPN communication. Please note that the addresses
used in the example.
Interface Addressing
This TechNote uses example addresses provided the VPN Consortium. It is important to
understand that you will be using addresses specific to the devices that you are attempting to
connect via IPSec VPN.
Figure 9-7: VPNC Example Network Interface Addressing
Gateway A
22.23.24.25 14.15.16.17
10.5.6.0/24 172.23.9.0/24
172.23.9.1 10.5.6.1
WAN IP WAN IP
LAN IP LAN IP
Gateway B
VPNC Example
Network Interface Addressing