Private Integrated Services Network (PISN);Inter-exchang
e signalling protocol;Generic functional protocol for the support of supplementary services [ISO/IEC 11582 (1995), modified] (Endorsed by Asociación Española de Normalización in May of 2022.)
Private Integrated Services Network (PISN);Inter-exchange signalling protocol;Generic functional protocol for the support of supplementary services [ISO/IEC 11582 (1995), modified] (Endorsed by Asociación Española de Normalización in May of 2022.)
