Call Sentry is a function provided by the TriVOX series of stand-alone on-premises end user modules performing like a miniature Auto-Attendant subsytem commonly found in large business telephone switches. Knowing the owner's changeable security code (i.e., the extension number), welcome callers are automatically patched through quickly. On the other hand, unwanted callers are offered the option to leave voice messages without disturbing the premises occupants. This stealthy process avoids direct confrontation thus relieves the owner of the concern about potential retalitray actions from the blocked callers.