Dell SonicWALL GX250 Manual page 119

both the central office SA and the remote site SA. Traffic is now able to go from branch
office to branch office via the corporate office.
Route all internet traffic through this SA
Checking this box allows a network administrator to force all network traffic to the WAN
to go through a VPN tunnel to a central site. Outgoing packets are checked against the
remote network definitions for all Security Associations (SA). If a match is detected,
the packet is then routed to the appropriate destination. If no match is detected, the
SonicWALL checks for the presence of a SA using this checkbox. If an SA is detected,
the packet is sent using that SA. If there is no SA with this option enabled, and if the
destination does not match any other SA, the packet goes unencrypted to the WAN.
This checkbox is used for configuration of remote site Security Associations.
Note: Only one SA may have this checkbox enabled.
Default LAN Gateway
A Default LAN Gateway is used at a central site in conjunction with a remote site using
the Route all internet traffic through this SA checkbox. The Default LAN
Gateway field allows the network administrator to specify the IP address of the
default LAN route for incoming IPSec packets for this SA.
Incoming packets are decoded by the SonicWALL and compared to static routes
configured in the SonicWALL. Since packets may have any IP address destination, it is
impossible to configure enough static routes to handle the traffic. For packets received
via an IPSec tunnel, the SonicWALL looks up a route for the LAN. If no route is found,
the SonicWALL checks for a Default LAN Gateway. If a Default LAN Gateway is
detected, the packet is routed through the gateway. Otherwise, the packet is dropped.
This checkbox is used if configuring a central site Security Association for a VPN tunnel.
SonicWALL Internet Security Appliance Guide Page 119