ÖNORM EN 300064-6 V 1.4.3:2000-01
Действует
Integrated Services Digital Network (ISDN) - Direct Dialling In (DDI) supplementary service - Digital Subscriber Signalling System No. one (DSS1) protocol - Part 6: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification for the network (incl. Diskette!!!)