PTT Abbrev. for Postal, Telegraph, and Telephone Administration. Each member country of the CCITT (for all practical purposes every country in the world) has a PTT, which is that country's representative on the CCITT. In those countries where the provision of communications services remains as a government monopoly, the PTT will be the agency that delivers the communications services, both internally and for international connections. In countries where there is no longer a government monopoly, the PTT will still be responsible for the issue of licenses and may also be one of a number of competing suppliers of communications services.

The image of the PTTs was as suppliers of limited data communications, based on speech-quality circuits operating at low bit rates up to say 9600 bps, and in some countries this persists. However, in response both to competition from other suppliers and to the growing demands of the marketplace, many PTTs are now aggressive suppliers of innovative high-grade services, offering digital services with operating speeds over the full range from a few hundred bps up to tens or hundreds of Mbps, and with extensive interworking with other suppliers for both domestic and international traffic.

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• Postal, Telegraph, and Telephone Administration