Private Integrated Services Network (PISN) - Inter-exchange signalling protocol - Message waiting indication supplementary service (ISO/IEC 15506 (2003), modified) (Endorsement of the English version EN 301255 V1.2.1 (2004-01) as German standard)
Edition 2004-12

Private Integrated Services Network (PISN) - Inter-exchange signalling protocol - Recall supplementary service (ISO/IEC 15052 (2003), modified) (Endorsement of the English version EN 301258 V1.2.1 (2004-01) as German standard)
Edition 2004-12

Private Integrated Services Network (PISN) - Inter-exchange signalling protocol - Simple dialog supplementary service (ISO/IEC 21408 (2003), modified) (Endorsement of the English version EN 301921 V1.1.1 (2004-01) as German standard)
Edition 2004-12

Private Integrated Services Network (PISN) - Inter-exchange signalling protocol - Generic functional protocol for the support of supplementary services [ISO/IEC 11582 (2002) modified] (Endorsement of the English version EN 300239 V1.3.1 (2003-06) as German standard)
Edition 2004-03

Private Integrated Services Network (PISN) - Specification, functional model and information flows - Call intrusion supplementary service [ISO/IEC 14845 (1996) modified] (Endorsement of the English version EN 300425 V1.3.1 (2003-06) as German standard)
Edition 2004-03

Private Integrated Services Network (PISN) - Mapping functions for the employment of 64 kbit/s circuit mode connections with 16 kbit/s sub-multiplexing (ISO/IEC 17310 (2002), modified) (Endorsement of the English version EN 301039 V 1.2.1 (2002-09) as German standard)
Edition 2003-12

Private Integrated Services Network (PISN) - Specification, functional models and information flows - Call interception Additional Network Feature (ANF) (ISO/IEC 15053 (2003), modified) (Endorsement of the English version EN 301256 V1.2.1 (2004-01) as German standard)
Edition 2004-12

Private Integrated Services Network (PISN) - Inter-exchange signalling protocol - Call intrusion supplementary service (ISO/IEC 14846 (2003), modified) (Endorsement of the English version EN 300426 V1.3.1 (2004-01) as German standard)
Edition 2004-12

Private Integrated Services Network (PISN) - Specification, functional models and information flows - Recall supplementary service (ISO/IEC 15051 (2003), modified) (Endorsement of the English version EN 301257 V1.2.1 (2004-01) as German standard)
Edition 2004-12

Private Integrated Services Network (PISN) - Inter-exchange signalling protocol - Call interception Additional Network Feature (ANF) (ISO/IEC 15054 (2003), modified) (Endorsement of the English version EN 301265 V1.2.1 (2004-01) as German standard)
Edition 2004-12