Signalling System No. 7 ISDN User Part general functions of messages and signals Amendment 1: Support for the International Emergency Preference Scheme SERIES Q: SWITCHING AND SIGNALLING Specifications of Signalling System No. 7 ISDN user part Study Group
The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical,