| 摘要 |
In a telecommunications system with 64 kbit/s standard channels (L), only one 56 kbit/s main channel, in each case passing from subscriber to subscriber (Tln), is used for voice, high-speed data or high-speed fixed image transmission and one 8 kbit/s inslot-output auxiliary channel for transmission of signalling characters, low-speed fixed image or low-speed data transmission and transmission of end-to-end signalling and telecontrol information; in the exchanges (ÖVST), the inslot-output auxiliary channels are constantly monitored and auxiliary channel signals are added or removed according to inserted service indication signals. When signalling characters transmitted from an exchange (ÖVST) coincide with signals of the other types, the exchange (ÖVST) has priority; it interrupts the transmission of the characters of one of the other types and performs signalling character transmission; the original transmission process is then continued. <IMAGE>
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