Two Airport Expresses extending the same network and a weekly password rotation? I just installed two Airport Express routers in a restaurant to improve their wifi coverage.  The first device (AE1) is connected to the restaurant's DSL router via ethernet, and the second device (AE2) extends the network created by AE1 via wireless.  This is set up and working perfectly.  

The problem is, the restaurant is close to a lot of residential stuff, and they've had issues with people pirating their signal.  So, obviously, they would like to password protect their wifi, changing the password weekly, and providing it to customers upon request.  This would be simple enough with one device, but I'm confused as to how I can go about it with two devices.  

Should I set up the WPA/WPA2 on AE2 first, then AE1?  Will AE2 even be able to extend AE1 if AE1's network is password protected?  I have many questions, but they all boil down to, is this even possible, and how can I do it?
If AE1 (plugged into the router) is setup as a wireless access point, then put a WPA/WPA2 password on that wireless network.

If AE2 is setup via Airport utility to "extend" the wireless network of AE1, then it will automatically inherit the password setup from the primary (in this case AE1).  Any password changes you make to AE1 will be transparent and update across both devices.

If you have setup AE2 to "join" a wireless network, this will not happen.

With "extend" the end user will only see one wireless network, with the same name, not two different devices.  Unless you have set your network up differently.