ITU-T stands for International Telecommunications Union. It is based in Geneva Switzerland. It was the International Telegraph Union before the advent of telecommunications. Then it became the International Telegraph and Telephone Consultative Committee in 1956 and lastly it was renames as ITU-T in the year 1993.
The GSM association is responsible and incharge of the GSM Service around the world. The key goals of this organization is to ensure that the mobile phones and wireless connections work on global basis and are easily accessible so that they are of value to the individual consumers as well as national economies.
It represents over 750 GSM mobile phone operators in around 218 countries. And 200 manufacturers and suppliers are supportive partners of GSM association and its initiatives.