Abstract: A system and method for discriminating call content types for individual telephone lines at a plurality of user sites outside of a Public Switched Telephone Network (PSTN) is described. The system includes: a database containing security rules for each of a plurality of extensions, the rules specifying actions to be taken based upon a call content type of the call on the extension, wherein the call content type is determined at the user sites outside the PSTN; and a line sensor within the user sites outside the PSTN for determining the call content type of the call. The line sensor continuously checks the call content type to determine if the call content type changes.