PURPOSE: To attain registration operation of an extension line of the registration operation of the third party as to any of mutual extension call or camp-on of a trunk line and to attain transfer connection by providing a waiting service function to an incoming call from a relay line.
CONSTITUTION: The system consists of a channel network device (NW)1, plural (A, B, C, D) extension telephone sets 3 connected via the channel network device 1, plural line circuits (LCs) 2 provided between each of the telephone sets 3 and the channel network device 1 and performing processings such as detection of call and dial reception, a call signal transmitter (RSIG)4 connected to the line circuit 2 and transmitting a call signal, a signal reception distributor (SRD)6 connected to the channel network device 1, identifying the device in the channel network device 1 designated by decoding the received information and distributing data to the device 1 or a driving circuit, a central controller (CC)7 connected to the signal outgoing distributor 6 and performing exchange control based on the stored control program, and a main storage device (MM)8 storing information relating to the exchange control.
TADA NAOHITO
MURAMOTO TSUGUO
