Telephone signal processing for credit assessment calls - using switching centre including dual tone multifrequency processor for allowing urban network connection with intelligent network employing two-tone signalling

摘要

The operation of the logic depends on a switching centre (SSP). When an urban centre call (101) is sent out, the switching centre receives a number (103) via the R2MFC signalling method. The centre determines (104) whether this is a call for services, via the intelligent network or a normal call. If it is a normal call it switches to the R2MFC network (105). If it is a call for services, the centre determines whether it is a credit rating call (108). If it is not, the call is switched to the intelligent service network (111) via R2MFC signalling (110). In the case of a credit assessment call, the R2MFC signalling is freed (114), and the path for the call is determined (115). The two tone signalling (116) is put into operation. The sender is then asked for his identity number (118), and following the receipt of this, the message is released (119). At the same time, the callers telephone number (121) is stored for future charging. Following the call the signalling path is cleared. USE/ADVANTAGE - Allows existing method of inter-urban connection to be used with two tone subscriber signalling.