Transatlantic cables, number of channels, and their cost [1] Cable name Years in service No. of channels Cost per channel ($) TAT-1 1956-1978 34 000 TAT-2 1959-1982 15 000 TAT-3 1963-1986 10 000 TAT-4 1965-1987 10 000 TAT-5 1970-1993 TAT-6 1976-1994 TAT-7 1978-1994 Broadband Telecommunications Technologies and Management With higher capacity, statistical multiplexing efficiencies grew reducing the need for call bookings. Subscribers could place international calls directly and without the need to go through operators. The cost of calling also dropped to $1-2 per minute and was within the reach of many subscribers. As a result, calling relatives and friends in other countries, especially on special occasions such as at Christmas and New Year, became common. After the mid-1960s geostationary telecommunications satellites also added capacity to the international telephony market, further reducing the cost of the long-distance phone calls. Case Study Questions How important was an understanding of teletraffic engineering to the designer of transoceanic international telephony cables such as TAT-1? Why was TAT-1 rolled out SO long after the invention of telephony? What were the business issues and why did the price per call drop SO dramatically? Who were the initial TAT-1 customers? Why did this change? What were the roles of governments in rolling out of transoceanic telephony cables? Telephone Operator Business Alexander Graham Bell envisioned that telephony would become an infrastructural utility. As he wrote to his father on the evening after his successful experiment: 'I feel that I have at last found the solution of a great problem, and the day is coming when telegraph wires will be laid on to houses just like water or gas is, and friends will converse with each other without leaving homes' [8]. As Bell predicted, the telephony business soon became a necessary utility, and behaved as a natural monopoly business similar to gas and water. In fact telephony had a higher propensity to become a natural monopoly compa