I am currently using a Linksys WRT54G in Client bridge mode, and it work very well to connect my arduino wirelessly using the ethernet card to my LAN. I can run server software on the arduino, or arduino manager,and get flawless communication.
I purchased a mini wireless router that boasted client mode. The instructions say to set it as "repeater" and then plug the device you wish to bridge into the ethernet port on the mini router. I configured it to connect to our wireless router and it provides fast internet connection to its ethernet port. However, I can't figure out how to configure it so that it bridges to the existing LAN. The existing LAN is set up on subnet 192.168.1.X. That is the way I configured the Linksys router, and I turned off DHCP serving. The mini router is preconfigured to subnet 192.168.16.1 for its LAN address. Do I set the arduino board's address to this? Or to another address on the same subnet? Or do I need to set the mini router to the same subnet as the rest of the Lan, 192.168.1.X?
Edit: Here is something from the DD WRT website about client mode that suggests I will need to configure port forwarding:
The main router and secondary router (DD-WRT client mode) are on separate subnets. NAT is used between the routers. Thus, when port forwarding is needed it must be configured at both routers — not just on the main (host) router.
I configured it to connect to our wireless router and it provides fast internet connection to its ethernet port.
If you cannot access the mini router localnet devices from the wireless router localnet, then it probably uses a NAT between the mini router localnet and the localnet on your wireless router. That means you will probably need to route the mini router localnet ip subnet in the wireless router.
What are the make and models of the routers you are using?
The mini router is an LB BLMP-01 pocket router.
http://www.lefen.com/index.php/products/view?pid=60
The wireless router in our home is a D Link DIR 628.
The WRT54G on the robot running DD WRT was easy to set up as a client bridge on the same subnet as the DIR 628 and works well, but takes up a lot of real estate on my robot platform. This pocket router, if I can get it to work, would be much smaller. The pocket router was easy to set up for client mode, but its lan address is on 192.168.16.X. I tried setting up the arduino on that subnet, but nothing on the local net seems to be able to find it. The pocket router is working well as a client, providing internet access via its lan connection outlet.
If the D-Link is 192.168.1.x, and the LB is 192.168.16.x, then the LB is using a source NAT to the IP it has on the D-Link localnet.
You must route the 192.168.16.0/24 network to the LB router. However, the LB router may have a firewall that will prevent access.
Look in the D-Link user manual. I used this one online:
ftp://ftp2.dlink.com/PRODUCTS/DIR-628/REVA/DIR-628_MANUAL_1.20_EN.PDF
Page 50 shows how to route that network. You must find the WAN (wireless) ip of the LB router to do this. The wireless interface on the LB router will have a 192.168.1.x ip. That is the ip you must use in the D-Link route section as the gateway.
Set the destination ip as 192.168.16.0, the netmask as 255.255.255.0, and the interface is the wireless.