Stage 3 Description for Number Identification Supplementary Services Using Signalling System No. 7 Section 8 - Sub-Addressing (Sub) - Specifications of Signalling System No. 7 Study Group XI; 6 pp [Superseded: ITU-T Q.731 ITU-T Q.731]
The CCITT (the International Telegraph and Telephone Consultative Committee) is a permanent organ of the International Telecommunication Union (ITU). CCITT is responsible for studying technical, operating and tariff questions and issuing Recommendations o