In the 80s, you had HFAI (Hands-free answer intercom) on the AT&T Merlin system, and "Voice Call" (Aren't they *all* voice calls?) on the Nortel Meridian. The plus is that these systems emitted a tone upon answer. You could also switch them off. On SIP, all you need is a header for auto-answer and an obedient phone.

Is there a phone you can buy that has this feature built in? I need one for this specific purpose. I want to be able to call it, and listen in. I am not spying on anyone, I need to listen to a mechanic equipment that runs on its own for days at a time and see if it is still running without being there. Please let me know if you come up with anything, I have been searching everywhere and this video is the best I have found so far...

Continuing with the VoIP theme, this week I decided to throw in some security stuff as well. This video is about a few different setups of Auto Answer and why one man's feature is another man's vulnerability. kzfaq.info/get/bejne/lZmJnLBnndqol3U.html

Nikola