Number Identification Supplementary Services: Calling Name Identification Restriction - Series I: Integrated Services Digital Network Service Capabilities - Supplementary Services in ISDN (Study Group 1) 18 pp
ITU (International Telecommunication Union) is the United Nations Specialized Agency in the field of
telecommunications. The ITU Telecommunication Standardization Sector (l’TU-T) is a permanent organ of
the ITU. Some 179 member countries, 84 telecom ope