Call connection status supervision device

摘要

The device contains a control unit for the control of the connection between a network and a corresponding office line, to execute a function of the call connection between the office lines. An interface unit provides an interface to a first and to a second office line under the supervision of the control unit. A network unit connects the first and the second office lines with each other. The presence or absence of a signal entered by the network unit is recognised by a status supervision unit, for the supervision of the call connection status during the call connection function between the office lines.