Indians are accustomed to receiving a volley of unsolicited calls and messages soon after signing up on a new app or website, despite being on the do-not-disturb, or DND, list. You have the option to block them, but there are just too many of them.

Phone numbers typically reach telemarketers either because our personal data has either been sold off or forcibly taken away by hackers in a data breach.

There has been a spate of data breaches of late, and Indians are definitely much more cautious about the details they share online, but sometimes there is no choice.

We continue to share mobile numbers and email addresses to shopping apps, food delivery services, telecom companies, and government portals. And once you click “I Accept”, you really have no control over where those details go.

When the water went over the head, the Indian government eventually decided to step in, and passed the Digital Personal Data Protection Act in 2023 to deal with cases of data misuse.

The Act forces companies to explain exactly how they're using the customer data that they collect. The law also arms individuals with the right to give or withdraw consent, allowing them to decide who can use their personal information.

It sounds perfect on paper. But for companies managing crores of records, it is a serious operational headache just to prove they're handling our data correctly.

This is where technology like blockchain could step in and help solve this part of the problem.

Tracking Data Mismatch

Blockchain is a tamper-resistant digital ledger implemented in a distributed fashion without any central repository. In other words, instead of one company or entity controlling the entire database, the information is stored across several computers in a network.

At their basic level, they enable a community of users to record transactions in a shared ledger within that community, ensuring that no transaction can be changed once published.

The blocks together create a perfect audit history of transactions. One can go back and see a former version of the database at any point in time.

If someone tries to modify a record, the system detects the mismatch across the network, creating perfect transparency of all data recorded.

Marketing and advertising companies that deal directly with customers are already testing this approach.

For example, Brave browser uses a blockchain-based system called Basic Attention Token, with which it tracks users secretly across websites.

The browser asks visitors if they want to see advertisements. If they agree, they receive small digital tokens for their attention. Users actively choose whether their data or browsing behaviour can be used for advertising.

The permission granted by the user is saved, enabling advertisers to receive only verified engagement instead of relying on hidden tracking tools.

Blockchain is also being used in digital identity management using zero-knowledge proof, or ZKP.

In this technology, a user’s personal information or identity credentials are saved in a digital wallet linked to a blockchain network.

Using this wallet, the user controls whether he wants to grant or withdraw permission to use his data, or share only partial information.

For example, if you only need to confirm whether you are above a certain age or live in a certain city, you can do that with the click of a button on your wallet without sharing the data of birth or complete residential address.

Tracking Data Use

A major weakness in today’s internet systems is that once data enters a company database, the individual loses control over it. He may nor may not have given permission to use his data, but he cannot prove it.

But he can in a blockchain-based system, which clearly saves when the consent was first given and when it was withdrawn.

With the government tightening the data privacy rules, businesses can easily show compliance by proving when the user consent was given and how the data was used.

But this system has its limitations. It cannot eliminate every data privacy risk. But it can certainly help companies become more compliant and accountable.

This series is brought to you in partnership with Algorand.