METHOD FOR IDENTIFYING A CALLING SUBSCRIBER BASED ON THEIR IDENTIFICATION IDENTIFICATION IN A TRANSMISSION SWITCHING CENTER OF A TELEVISION AND DATA SWITCHING SYSTEM.

摘要

1. A method of identifying, on the basis of its calling line identification, a calling subscriber station (TlnA) connected to an originating exchange (UVST) of a teleprinter- and data switching system which comprises at least the originating exchange, at least one transit exchange (DVST) and at least one terminating exchange (ZVST) in order to calculate charges relating to connections from this subscriber station via transit exchange, where such a connection is established in that firstly a selection information is transmitted from the originating exchange to the terminating exchange whereupon, prior to the emission of a switch-through signal (ZD) which indicates the swich-through or seizure of the terminating exchange, the terminating exchange supplies the originating exchange with a first control signal (S1) which switches through the transit exchange and which indicates that further control signals are available in the terminating exchange for the respective connection establishment, and/or which requests the emission of the calling line identification of the calling subscriber station connected to the originating exchange from this originating exchange for a called subscriber station connected to the terminating exchange, and that by means of the switch-through signal emitted from the terminating exchange the connection is switched through via the originating exchange to the calling subscriber station, and by means of a signal (UD) which is derived from the respective switch-through signal and is transmitted to the terminating exchange the establishment of the connection is indicated to the called subscriber station (TlnB), characterized in that in the event that the first control signal (S1) only indicates the availability of further control signals it is modified in the transit exchange (DVST) in such manner that the respective calling line identification is made available to the transit exchange by the originating exchange (UVST) to which the respective calling suscriber station (TlnA) is connected, by which this calling line identification, in the same way as the calling line identication, which was made available as a result of the transmission of a control signal requesting the emission of the calling line identification, where appropriate together with the previously received selection information relating to the called subscriber station (TlnB), is made available for charge metering.