I've been trying to setup WDS using two of these routers and DD-WRT. It has been nothing but a headache. After an hour or so the client router stops responding on wireless. I started this experiment with a WNR3500L as the primary router and a WRT54GS as the client and had the same problems. I've tried using WPA2 and switched to WPA to hopefully solve my connection issues. It hasn't. I think WDS and DD-WRT are broken. Don't go to the DD-WRT forums for help either. The members there are apparently far too proud to deal with anyone else's problems and will give you an attitude. I'm a network engineer and I haven't been able to make this thing work. I wish there was a firmware closer to a CISCO setup I could use. Then I'd be able to get somewhere.

No I mean client router as in a second router that is not the gateway or DHCP server. I updated the firmware to the most recent DD-WRT listed on this website and so far things seem ok. It stayed up for several hours yesterday. I'll post more details if it's still up when I get home tonight.

Ok, here's what I have so far. I'm currently running WPA Personal with AES, but my secondary router was still loosing it's connection. I found an option for WDS/Watchdog. I enabled it and set it to my main routers IP polling every 1 minute. This option makes the router ping the ip given (in this case my main router) every minute. If it doesn't receive a reply it reboots the router. So far so good. I have no idea how often it reboots, but every time I've needed it it's been there.

Wireless driver in WNR3500L supports WPA. I am not sure about WDS. If it supports that feature then it should work.