Could quantum computers undermine the security of Blockchain transactions?

In 2018, blockchain transactions are on the rise for shipping, finance and other industries partly due to cryptographic structures which make financial transactions secure.

Unfortunately, some computer experts are warning that blockchain security is based on digital computing whose security capabilities may soon be breached by next-generation quantum computers.

In the November 22^ndissue of the scientific magazine, Nature, a team of Russian quantum computer experts reported on blockchain’s vulnerability in an article entitled “Quantum computers put blockchain security at risk.”

The Russians argue that quantum computers “will soon be able to outperform” conventional digital computers “on certain tasks.” One such example, they say “is breaking security protocols that are based on cryptographic algorithms, as mathematician Peter Shor pointed out in 1994…A blockchain is particularly at risk from this because one-way functions are its sole line of defense…Cracking of digital signatures is therefore the most imminent threat. A wrongdoer equipped with a quantum computer could use Shor’s algorithm to forge any digital signature, impersonate that user and appropriate their digital assets.”

The functions used to secure the Internet and financial transactions will “instantly become obsolete” by quantum computers within the next ten years, they warn.

The authors, Aleksey Fedorov, Evgeniy Kiktenko and Alexander Lvovsky, are associated with the Russian Quantum Center in Moscow. They note that tightening security and the use of alternative encryption could help buy time for existing blockchain systems. 

However, “the longer-term answer is to develop and scale up the quantum communication network and, subsequently, the quantum internet. This will take major investments from governments.”

The authors note that China, the United States and the European Union will be “among the early adopters” of quantum computer technology and they urge more investment in research: “Much greater urgency needs to be given to these risks—their impact could be grave.”