Hype springs eternal

NORMALLY, it is Simon Taylor’s job to persuade sceptical colleagues at Barclays that rapid technological change will disrupt the bank’s business. So it comes as something of a surprise to have to dampen the excitement about the blockchain. “It’s quite silly. I get ten invitations to speak at a conference every day,” he says. “The technology will have real impact, but it will take time.”

The blockchain is the technology underpinning bitcoin, a digital currency with a chequered history. It is an example of a “distributed ledger”: in essence, a database that is maintained not by a single actor, such as a bank, but collaboratively by a number of participants. Their respective computers regularly agree on how to update the database using a “consensus mechanism”, after which the modifications they have settled on are rendered unchangeable with the help of complex cryptography. Once information has been immortalised in this way, it can be used as proof of ownership. The blockchain can also serve as the underpinning for “smart contracts”—programs that automatically execute the promises embedded in a bond, for instance.