How to divide traffic based on subnets?

Question

I'm planning on getting a second broadband in addition to my current one. What I'd like to know is how can I divide the traffic so that the second connection is used only for certain subnets and the other one for everything else. Can this be done in Windows or do I need a separate PC for routing?

EDIT: some additional info:

I'm planning a setup like this:

Connection #1 (eth0)

• Wired via router
• 100Mbps
• Limited traffic

Connection #2 (wlan0)

• Wireless via router #2
• 10Mbps
• Unlimited traffic

If configured this way, connection #1 is the one to limit to specific subnets and connection #2 is used for all others.

I could also be persuaded to use a linux box for this division (assuming this can be done with basic tools like iptables etc.), but a Win7 solution is preferred.

Answer 1

First: Set your default-route (standard gateway) to the ip of router2.
Second: add the specific subnets manually to your routing table pointing to the ip of router1.

route ADD *network* MASK *subentmask* *gateway*  

for example if the network is 10.24.0.0/16 and the IP of router1 is 192.168.56.1:

route ADD 10.24.0.0 MASK 255.255.0.0 192.168.56.1

Forgot to mention:If it works as you like, use the -p argument to make the route persistant. (Be configured after reboots.)