The chairman of India's telecoms regulator says that use of digital identities, biometrics and the country's Aadhaar ID number can cut new account activation costs to zero.TRAI chairman R S Sharma told the Business Standard that if electronic KYC is conducted via Aadhaar then transaction costs are reduced substantially.”If you are taking a mobile connection, currently the cost of activation of a mobile customer is Rs 150 because you have to fill a customer acquisition form (CAF), you have to give paper documents… If you use digital identity authentication, you can fill the customer form, digitally sign it and get your electronic KYC. So, essentially the cost is equal to zero,” Sharma said at the annual growth Net in Delhi.When he served as the UIDAI Director General and then as Department of Electronics and IT (Deity) Secretary, Sharma had earlier recommended make the whole process paperless.Linking Sim card registrations to identities is an increasingly hot topic in South Asia, with neighbouring countries Pakistan and Bangladesh undergoing biometric SIM registration for the whole mobile population.