info-vax@ucbvax.ARPA (01/02/85)
From: Allan A. Miller <AAA@SU-AI.ARPA> I have seen security devices that allow dial-in lines, but respond to calls by asking for the caller's phone number, hanging up, and then calling back only numbers that are in a list of "authorized" callers. It seems like this would be pretty easy to do with a phantom that watches a TTY line connected to a Hayes modem (or any modem that can do dialing, for that matter). Has anyone seen a program that does this and runs under VMS?