Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Data link layer - Part 1: General aspects [ITU-T Q.920 (1993), modified]; English version ETS 300402-1:1995
Edition 1996-06

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Data link layer - Part 2: General protocol specification [ITU-T Q.921 (1993), modified]; English version ETS 300402-2:1995
Edition 1996-06

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Data link layer - Part 3: Frame relay protocol specification; English version ETS 300402-3:1996
Edition 1997-04

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Data link layer - Part 5: Protocol Implementation Conformance Statement (PICS) proforma specification for the frame relay protocol; English version ETS 300402-5:1996
Edition 1997-04

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Data link layer - Part 6: Test Suite Structure and Test Purposes (TSS&TP) specification for the general protocol; English version ETS 300402-6:1997
Edition 1997-11

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Signalling network layer for circuit-mode basic call control - Part 4: Test Suite Structure and Test Purposes (TSS&TP) specification for the user; English version ETS 300403-4:1997
Edition 1997-11

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol; signalling network layer for circuit-mode basic call control - Part 5: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification for the user; English version ETS 300403-5:1997
Edition 1998-08

Broadband Integrated Services Digital Network (B-ISDN) - Signalling system No. 7 - Interworking between Broadband ISDN User Part (B-ISUP) and Digital Subscriber Signalling system No. 2 (DSS2) (ITU-T Q.2650:1995, modified); English version ETS 300495:1997
Edition 1998-02

Digital cellular telecommunications system (Phase 2) - Information element mapping between Mobile Station-Base Station System (MS-BSS) and Base Station System-Mobile-services Switching Centre (BSS-MSC) signalling procedures and the Mobile Application Part (MAP) (Endorsement for the English version ETS 300605:1998-05 as German standard)
Edition 2001-04

Broadband Integrated Services Digital Network (B-ISDN) - Digital Subscriber Signalling System No. two (DSS2) protocol; Direct Dialling In (DDI) supplementary service - Part 1: Protocol specification [ITU-T-Recommendation Q.2951, clause 1 (1995), modified] (Endorsement of the English version ETS 300661-1:1997 as German Standard)
Edition 2000-05