scope:

This European Standard (Telecommunications series) has been produced by ECMA on behalf of its members and those of the European Telecommunications Standards Institute (ETSI). The present document is one of a series of standards defining services and signalling protocols applicable to Private Integrated Services Networks (PISN). The series uses the Integrated Services Digital Network (ISDN) concepts as developed by ITU-T and conforms to the framework of standards for Open Systems Interconnection (OSI) as defined by ISO/IEC.