Telecom, which was in effect a preserve of the elite, has since then become a partner in progress for the masses. The revolution in the telecommunications sector has affected not only its functional sphere but all walks of life, redefining the rules of business with each technological accomplishment in the sector. India has one of the largest telecom networks in Asia comprising about 25,000 telephone exchanges, with a total equipped capacity of 26.05 million lines and 21.59 million working telephones. More than 99 per cent telephone exchanges in the country are of electronic type, covering more than 98 per cent of the installed capacity. The long-distance transmission network has about 1,49,000 route-km of radio systems and about 1,08,032 route- km of optical fibre systems. Fully automatic International Subscriber Dialling (ISD) service is now available to almost all countries. The total number of stations connected to National Subscriber Dialling (NSD) is over 18,000. In the field of global communications, tremendous progress was made by the use of satellite and submarine links.