So... I got tired of the overpriced IP door phones that never worked right. I used to use these analog Viking door units years ago and remember them being rock solid, but never thought of integrating it with a IP system. I connected this one up to my Asterisk system using a Linksys PAP2T-NA analog telephone adapter. As this Viking unit has a programmable auto dialer, it simply picks up the line and dials my ring group. No problems, no complicated SIP setup, and best of all it's half the price of those SIP door phones! I also believe that this one will last longer. Viking has always made quality products and this one is no exception. I do not worry about this phone being exposed in a public area at all.This unit also has adjustable speaker an mic level controls - something that is lacking in the IP door phones. The auto-dialer function couldn't be easier to program. Simply flip a DIP switch in the unit and call it from a phone. The unit answers and you punch in the number you want it to dial. Flip the DIP switch back and you're set!If you're considering using this with a IP based system but don't know if it will work, you now have your answer.