Netgear 05200007 User Manual

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Reference Manual for the NETGEAR ProSafe VPN Client
B-8
Virtual Private Networking
202-10015-01
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.
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.
Table B-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
Table B-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