Stage 3 Description for Additional Information Information Transfer Supplementary Services Using DSS 1 Clause 1 - User-to-User Signalling (UUS) - Digital Subscriber Signalling System No. 1 - Stage 3 Description for Supp. Services Using DSS 1 (Study Group
The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the International Telecommunication Union. The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to