NETGEAR FVS124G manual Setting Up a VPN Tunnel Between Gateways, Firewalls, Subnet Addressing

Reference Manual for the ProSafe VPN Firewall 25 with 4 Gigabit LAN and Dual WAN Ports

It is also important to make sure the addresses do not overlap or conflict. That is, each set of addresses should be separate and distinct.

Table 9-1.	WAN (Internet/Public) and LAN (Internal/Private) Addressing
Gateway		LAN or WAN	VPNC Example Address
Gateway A		LAN (Private)	10.5.6.1
Gateway A		WAN (Public)	14.15.16.17
Gateway B		LAN (Private)	22.23.24.25
Gateway B		WAN (Public)	172.23.9.1

It will also be important to know the subnet mask of both gateway LAN Connections. Use the worksheet in Appendix A to gather the necessary address and subnet mask information to aid in the configuration and troubleshooting process.

Table 9-2.	Subnet Addressing
Gateway		LAN or WAN	Interface Name	Example Subnet Mask
Gateway A		LAN (Private)	Subnet Mask A	255.255.255.0
Gateway B		LAN (Private)	Subnet Mask B	255.255.255.0

Firewalls

It is important to understand that many gateways are also firewalls. VPN tunnels cannot function properly if firewall settings disallow all incoming traffic. Please refer to the firewall instructions for both gateways to understand how to open specific protocols, ports, and addresses that you intend to allow.

Setting Up a VPN Tunnel Between Gateways

A SA, frequently called a tunnel, is the set of information that allows two entities (networks, PCs, routers, firewalls, gateways) to “trust each other” and communicate securely as they pass information over the Internet.

D-8 Virtual Private Networking

202-10085-01, March 2005