3COM NBX Network Branch Exchange The NBX phone system is a true computer network based system This gives the 3COM system advantages over traditional PBX and key systems Voice mail is standard on the 3COM system, and is expandable by simply adding a keycode Because the voice mail system is "virtual" there are no moving parts to wear out or replace. Adding phones is a simple as plugging into a computer hub. There are no additional circuit packs needed.      More     Standard features Voice mail Call Detail Recording Network accessed user guides and phone labels