I need to figure out a way to allow access to two LAN subnets on a SonicWall NSA 220 through the built-in SonicWall GlobalVPN server. I've Googled and tried everything I can think of, but nothing has worked. The SonicWall NSA management web interface is also very unorganized; I'm probably missing something simple/obvious.

There are two networks, called Network A and Network B for simplicity, with two different subnets. A SonicWall NSA 220 is the router/firewall/DHCP Server for Network A, which is plugged into the X2 port. Some other router is the router/firewall/DHCP server for Network B. Both of these networks need to be managed through a VPN connection.

I setup the X3 interface on the SonicWall to have a static IP in the Network B subnet and plugged it in. Network A and Network B should not be able to access each other, which appears the be the default configuration. I then configured and enabled VPN.

The SonicWall currently has the X1 interface setup with a subnet of 192.168.1.0/24 with a DHCP Server enabled, although it is not plugged in. When I VPN into the SonicWall, I get an IP address supplied by the DHCP Server on the X1 interface and I can access Network A remotely although I do not have access to Network B.

How can I allow access to both Network A and Network B to VPN clients although keep devices on Network B from accessing Network A and vice-versa.

Is there some way to create a VPN-only subnet (something like 10.100.0.0/24) on the SonicWall that can access Network A and Network B without changing the current network configuration or allowing devices on both netorks "see" each other? How would I go about setting this up?

Diagram of the network: (Hopefully this kind of helps)

       WAN1                                    WAN2
        |                                       |
[ SonicWall NSA 220 ]-(X3)-----------------[ Router 2 ]
        |                                       |  
       (X2)                               192.168.2.0/24
    10.1.1.0/24

Any help would be greatly appriciated!