Firewalls, Setting up a vpn tunnel between gateways – NETGEAR ADSL Firewall Router DG834 User Manual
Page 196
Reference Manual for the ADSL Firewall Router DG834
D-8
Virtual Private Networking
202-10005-05, June 2005
It will also be important to know the subnet mask of both gateway LAN Connections. Use the
worksheet in
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 D-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 D-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