Can I build two WLANs with Tomato?

Question

My problem is this: I have a couple of devices connected to a WRT54GL with Tomato in the same network, both wireless and wired. I want to grant access to the internet to a notebook via wireless but i don't want it can connect to any previous device connected to the router. I suspect that I need to create multiple WLANs, probably each one with its own SSID but I don't know how. It is posible with Tomato? If it is posible, it is probably be done using the command line because there is nothing like that in the web interface. Do anybody know any good reference to start? Thanks in advance.

Edit: I have a Linksys WRT54GL 1.1 and I prefer to use a single router. I know this is posible in DD-WRT but any reference is good.

Answer 1

To build two WLANs you need

• a wireless device that supports multiple SSIDs and can confine traffic from each SSID to its own VLAN, or
• two wireless devices

Most home routers that I know of do not support multiple SSIDs. Some business DSL gateways do (Netopia) and I'm sure there's mid to high end Cisco gear that can do that.

However, many home routers have a feature called "AP Isolation" that something similar to what you describe - it will prevent wireless clients from talking to each other but will not prevent traffic between wired and wireless. If your router supported it before you flashed it, check if it's Tomato's "Advanced" menu.

If you have two WLANs and a separate router, you can put each WLAN on its own subnet. Therefore, traffic to reach one subnet to another MUST go through a router. At the router you can use firewall or traffic rules to prevent clients from talking to each other. I'm not sure if Tomato supports putting the WLAN on a separate subnet, and I don't know to what extent you could put filtering rules using the Tomato UI (if you can enter iptables commands anything is possible though).

Answer 2

Set the DHCP on one router to assign IP addresses in the form 192.168.1.X and the other router to assign IP addresses of the form 192.168.2.X.