Method and circuit for the transmission of data signals and signalling information between data terminal equipment, which is interconnected through the exchanges of a telecommunication network

摘要

1. A method of transmitting data signals (D) and items of signalling information (Sa, Sb) between data terminal devices (DTE) which are connected to one another via exchanges (VSt) of a telecommunications network in which, for the transmission of the data signals (D) and the items of signalling information (Sa, Sb), there are provided data transmission paths (NK) and signalling paths (SK) which are separate from one another, and in which the data transmission paths (NK) can be additionally used to transmit signals (Sa', A, Sb', B) which differ from data signals (D), where the establishment and clearance of connections between data terminal devices (DTE) takes place in that the exchange (VSt) in question is supplied with special items of signalling information (Sa, Sb) via the signalling path (SK), characterised in that during a part of the interval in which a data terminal device (DTE) emits an item of signalling information (Sa) which serves to establish a connection to another data terminal device, via the signalling path (SK), a control signal (Sa') emitted from the aforementioned first data terminal device prior to the data signal emission and serving to actuate the other data terminal device designated for data signal reception, and an acknowledgement signal (A) indicating the actuation of the other data terminal device and transmitted from this other data terminal device to the first data terminal device in order to clear the transmission of data signals (D), are transmitted via the data transmission path (NK) which is to be used for data signal transmission between the two data terminal devices whick are to be connected or are connected to one another, without additional analysis or evaluation in the relevant exchange (VSt).