NETGEAR ProSafe FVS124G - Manual (Page 40)

Reference Manual for the ProSafe VPN Firewall 25 with 4 Gigabit LAN and Dual WAN Ports
3-10 Network Planning
202-10085-01, March 2005
VPN Gateway-to-Gateway: Dual Gateway WAN Ports for Improved Reliability
In the case of the dual WAN ports on the gateway VPN firewall ( Figure 3-13 ), either of the
gateway WAN ports at one end can initiate the VPN tunnel with the appropriate gateway WAN
port at the other end as necessary to balance the loads of the gateway WAN ports because the IP
addresses of the WAN ports are known in advance. In this example, port WAN_A1 is active and
port WAN_A2 is inactive at Gateway A; port WAN_B1 is active and port WAN_B2 is inactive at
Gateway B.
Figure 3-13: Dual gateway WAN ports, before rollover, for gateway-to-gateway VPN tunnels
The IP addresses of the gateway WAN ports can be either fixed or dynamic, but a fully-qualified
domain name must always be used because the active WAN ports could be either WAN_A1,
WAN_A2, WAN_B1, or WAN_B2 (i.e., the IP address of the active WAN port is not known in
advance).
After a rollover of a gateway WAN port ( Figure 3-14 ), the previously inactive gateway WAN port
becomes the active port (port WAN_A2 in this example) and one of the gateway VPN firewalls
must re-establish the VPN tunnel.
Gateway A
netgearB.dyndns.org netgearA.dyndns.org
10.5.6.0/24 172.23.9.0/24
172.23.9.1 10.5.6.1
WAN_A1 IP WAN_B1 IP
LAN IP LAN IP
Gateway B
Gateway-to-Gateway Example
(Dual WAN Ports, Before Rollover)
Fully-Qualified Domain Names (FQDN)
- required for Fixed IP addresses
- required for Dynamic IP addresses
VPN Router
(at office A)
VPN Router
(at office B)
WAN_B2 IP (N/A) WAN_A2 IP (N/A)
WAN_A2 port inactive WAN_B2 port inactive
X X X X