Blockchain is a marvelous technology. It relies on sophisticated cryptography to create a tamper-proof ledger across multiple computers, eliminating fraud and mistakes. It’s no surprise, then, that pundits are popping up who say using blockchain can avert the next Equifax breach.
Too bad it’s not that easy. While blockchain is poised to transform a lot of things—from shipping to the diamond industry—it can’t fix sloppy data practices at the credit bureaus.
According to David Treat, who leads the blockchain practice at Accenture, the architecture of blockchains is not designed for massive data sets. He explained that, in the case of Equifax, the company’s business practice is about using algorithms to query a massive repository of customer records in order to spit out a credit score.
While consumers and companies could use a blockchain to access the score, it’s still up to the credit bureaus to protect the underlying pool of personal information. Doing that, says Treat, requires segregating sensitive data and properly encrypting it.
“Their focus should be on the latest encryption and security techniques for hardening and protecting data sources,” he said, adding the same advice applies for large retailers and other institutions sitting on stacks of personal information.
But while blockchain can’t be a substitute for good data hygiene, the technology will have a role in helping individuals exert control over their identity. For example, Accenture and Microsoft are building blockchain tools that will help migrants and refugees access school and medical records. Meanwhile, Treat predicts that blockchains will be useful for age verification—meaning a young person could use a blockchain app instead of a state drivers license to enter a bar.
The bottom line is blockchain may be marvelous but it’s not a magic bullet.
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