Centrally controlled telephone systems with master exchanges and terminal exchanges (central data channel)

摘要

The invention relates to centrally controlled telephone systems with a central data channel and trunk lines, in particular dedicated telephone systems, with subscriber sets and/or line sets for analog and/or digital information transmission, where the subscriber sets and/or line sets can be interconnected via central switching stages. In the master exchange (HAL), part of the line group (LTGx) is removed and operated in the terminal exchange (EAL) as a system-configuration-individual line group (RLTGm). Both line groups (LTG, RLTG) in each case have dedicated group control devices (GP) which communicate with the central control device (CP) of the main exchange. The speech information can be transmitted via the trunk lines (FL...) and the control information via the central data channels (DK...). System configurations of this type are implemented in private dedicated telephone networks. IMAGE