Internal telephone network with interconnecting service position - extending blocking control criterion to transmission units to reserve automatic traffic working

摘要

The telecommunications circuit is esp. for internal networks served by an interconnecting service position. The exchange couplings can be established manually or automatically. An individual-selector-working, coupling transmission is provided for the communications not established via the transmission units coupled to the network. This individual transmission can be seized through the service position and reception of direction data, e.g. dialling code, and consequently coupled with appropriate transmission units via input leads by means of selectors. The service position reserves the automatic traffic by extending a blocking control criterium to the transmission units.