The Telecommunication Standardization Sector (ITU-T) coordinates standards for telecommunications on behalf of the International Telecommunication Union (ITU) and is based in Geneva, Switzerland. The standardization work of ITU dates back to 1865, with the birth of the International Telegraph Union. It became a United Nations specialized agency in 1947, and the International Telegraph and Telephone Consultative Committee (CCITT), (from the French name "Comite Consultatif International Telephonique et Telegraphique") was created in 1956. It was renamed ITU-T in 1993.

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