Broadband Integrated Services Digital Network (B-ISDN) - Digital Subscriber Signalling System No. two (DSS2); B-ISDN user-network interface layer 3 specification for basic call/bearer control - Part 3: Test Suite Structure and Test Purposes (TSS&TP) specification for the user (Endorsement of the English version EN 300443-3 V 1.2.1 (2001-06) as German Standard)