SYSTEM FOR PROVIDING TELEPHONY AND DATA SERVICES

A telephone on-hook/off-hook state communication system. The system includes a first part, for example in the form of an In-Line Analog POTS presentation Adapter, which is operable to interconnect between a telephone apparatus and a pair of conductors, and a second part operable to interconnect between the pair of conductors and a telephone adapter unit, the first part including a variable impedance and means for changing the impedance of the variable impedance such that a property of the impedance at a predetermined frequency (f) greater than zero changes in response to the telephone apparatus transitioning between an on-hook state and an off-hook state, the second part including a detector for detecting the change in the impedance of the variable impedance of the first part via the pair of conductors.