scope:

This European Telecommunication Standard (ETS) defines the minimum MMI for use to gain access to and control of supplementary services within public telecommunications networks. It describes the requirements to be met jointly by the service provider, the network operator and the terminal manufacturer necessary to ensure provision of the minimum MMI. This ETS applies to network based supplementary services provided within: - the Public Switched Telephone Network (PSTN) - the Integrated Services Digital Network (ISDN)