Have a DIR-655 at home and in a small remote office. Can one create a WAN connection between the two DIR-655's, or are there optional pieces of hardware I can obtain to create this?
I guess you ask if you can setup them like:
internet <-> DIR-655_1 <-> DIR-655_2
If so, yes you can. Also, on DIR-655_1 assign the WAN IP of the DIR-655_2 as a DMZ. If you still have problems let me know and I will draw a scheme for you.