You didn't mention a router between your dsl modem and your OBIs, but if you have multiple OBis at your remote site I would guess you must have one; if this is the case what model router do you have there? Most modern routers support dynamic dns from places like
http://dyn.com. If you don't have this setup then I would highly recommend it so that you can access your router and OBi control webpages remotely. You'd have to open a port on the router and point it to port 80 on your OBi so that you could access the OBi's website control/status.
Your router hands out the ip address to your OBi via dhcp. There are two ways to have this be a "fixed" or "static" address. One is to assign an ip address on your lan to the OBi using the OBi itself. A second way if your router supports it is to "reserve" an ip for your OBi's mac address; that way the router will always hand out the same ip address to your OBi while your OBi still operates in dhcp mode. It is handy to have a static lan address for your OBi so that you can find it at the same lan ip all the time.
It sounds as if your making arrangements to obtain a fixed ip for your wan which may or may not improve your connecting to the OBiTalk network. Each OBi sends out packets of information to the OBiTalk network to identify itself which contain the wan ip address currently assigned to your network periodically. I do not have experience with dsl where the ip changes more frequently since I have cable service and my wan ip is virtually static anyway. I would think the OBi's would report frequently enough to keep up with dsl ip changes but others with real experience may pop in to prove me wrong on this.
If your router supports remote access then you should be able to access it's status page and find out if your OBi is connected or not. I would suggest using SSL remote management or ssh which is even more secure if your router supports it.
The power device Stewart suggested would give you great flexibility and added reliability by being able to toggle the power on the remote devices yourself. I would suggest the
http://www.geeks.com/details.asp?InvtId=9258T-PING instead of the basic 9258 model because it adds the ability of the device to ping devices and automatically power cycle them if they do not respond to pings as you define.
The 9258-ping could periodically ping your OBi, and if the OBi does not respond, then the 9258-ping can cycle it's power to force the OBi to reboot. Likewise it can ping your router and perform the same function for it in case the router hangs. Using ping is a little harder for the modem itself, since you cannot ping it from the lan side, but it appears you could ping something like Yahoo or Google and if they do not respond then you could have the 9258-ping power cycle the dsl modem.
