Hi Bob.
Of course it is possible, that's how all users are doing. But you have to configure portforwarding or of the ports 80,5060,11000,12000 in the remote router. Or even more simple is to assign the RRC as DMZ server. All done in the remote router at the radio-QTH. Nothing has to be done at the control site router. If you are using IP-telephony at any of the QTH.s change the port 5060 in the RRC:s to something else for example 11001. Also remember to deactivate SIP ALG if your router has something like that ( d-link and netgear routers often has). Port 80 is not needed for the communication but is handy to use for status control, firmware upgrade etc. If port 80 is prohibited by the ISP, as I heard some US ISP are doing to prevent home webservers, just change the web server port to for example 8000 in the remote RRC.
73 de mike