bridging between two subnets

[ptiedemann]

Assuming that I simply have two 350 wireless bridges between two subnets 192.168.1.x and 192.168.2.x with no routers whatsoever what IP information should I be entering in the client PC's to connect with the other side. I was thinking that changing the subnet mask to 255.255.0.0 would solve this, but is this the only way?

[donewald]

You'll need to point each client on each network to it's default gateway router. Routers have a job of transiting data from network to network. Should be a router interface on each one of your 192.168.1 and 2.x networks. So assuming that your routers were .1 on each of the network you'd configure your clients like this.

Client 1 (1.x network) would have a default gateway of 192.168.1.1

Client 2 (2.x network) would have a default gateway of 192.168.2.1

For one making the mask 255.255.0.0 might not be supported by some clients since this would be a supernet (classless) mask. And even it supported this setup would require a proxy arp function to work which is not good practice to be reliant on.

Hope this helps you,

Don

[ptiedemann]

Well I have no routers to speak of. They use a proxy server to get to the internet. My more specific question is even if I manage to put a router in each location the bridge will only hear broadcast arp messages to relay them to the other side (or interface in this case). I see where you are going with this. The setup will work fine if we utilize a different subnet using the two bridges and a pair of routers but what if I don't have the router to place in front of the bridges. After testing the supernet seems to work for a pair of laptops placed on either side of the 350 bridges but your proxy arp question makes me a little nervous. What problems could creep up on me by using the supernet setup?

[donewald]

The supernet setup will continue to work for you if there is no proxy-arp functioning making this work. Proxy-arp is a function that is on by default on ethernet interfaces on Cisco routers and will make things work that normally would not. If your two bridges are somehow connected on the same BCAST domain then you've got nothing to worry about except possible hosts not supporting your supernet mask. If there is a router in the mix somewhere between the two, seems from your explaination that there is not, then someone could disable proxy-arp (common practice) and you'd stop working. One last thing, if you had to get to any non-local 192.168.x.x networks you'd not beable to get there due to your hosts thinking they are local... (again, something proxy-arp could make work).

Hope this helps you,

Don