New Delhi: Ajay Bhushan Pandey, chief executive officer of the Unique Identification Authority of India (UIDAI), told the Supreme Court on Thursday that while a 100% authentication success rate under Aadhaar was not possible, the law governing it took care of the same.

“Many variables like connectivity, machines not working may be responsible for authentication failure," Pandey said, addressing the technical and security aspects of the 12-digit unique ID in a 90-minute presentation before the Constitution bench hearing the challenge to Aadhaar.

UIDAI also claimed Aadhaar had a 2048-bit encryption key, which worked like a number lock, making it extremely secure. The fastest computer will take “an age of the universe to break it", Pandey said.

A day earlier, attorney general K.K. Venugopal representing the government had claimed that the central database holding Aadhaar data was secure behind a wall 13 feet high and 5 feet thick.

On Thursday, responding to concerns over the need for identity, enrolment, authentication, success rate, architecture and security, Pandey said Aadhaar was born on recognition of the need for a “robust and inclusive ID that was nationally verifiable".

“Statistically, everybody had an ID but it was not nationally accredited. For a bank account, one would need a ration card and for a ration card an electricity bill. To address this issue and extend it to everybody including migrants and children, Aadhaar was put in place," Pandey said.

UIDAI further assured the court of its secure enrolment process and said that every new enrolment was matched against all other enrolments in the system.

It also explained how an Aadhaar exemption policy was working towards issuing Aadhaar to those unable to provide their biometrics due to deformity, injury, etc.

“In such cases, we issue an Aadhaar without biometrics and use a PIN-based authentication process," he said.

Pandey said that although not mandatory, Aadhaar could be issued to a person as early at their birth. Details including biometrics would have to be updated at the age of 5 and then at 15 years of age.

At this point, justice Chandrachud questioned what would happen when a person’s biometrics change, for instance in case of manual workers.

Such individuals will have to go to enrolment centres and get their details updated, Pandey responded.

This did not find favour with justice Chandrachud who said this would lead to exclusion, as claimed by the petitioners in their arguments.

Taking the exclusion argument forward, Chandrachud questioned the UIDAI further whether the authority got to know about cases where there was denial of services under Aadhaar usage. Pandey assured the court that nobody would be denied services and that ministries were being asked to intervene on service denial.

In its opening argument in support of Aadhaar, attorney general K.K. Venugopal had said that Aadhaar was being used as an “enabler of the citizens’ right to life including their right to food, livelihood, pension and other social assistance benefits".