Call section and dial evaluation system - for automatic telephone exchanges and shares processing in assessing status of callers and connections

摘要

Centrally controlled, automatic, private branch exchanges have facilities for making connections between local subscribers, and for making trunk calls. They may also have facilities for special services such as automatic repeated dialling, conference connections, information services etc., each with its own control, processing and memory units, in addition to similar central units. Not all subscribers may be authorised to use the special services. The invention is arranged to economise on electronic storage and processing effort, in systems in which the caller's authority is assesses simultaneously with the viability of the desired connection. Connection is only made when these two conditions are acceptable.