Quantum Computing’s Impact on Cryptography & Blockchain Security
(CoinTelegraph) The advent of quantum computing could potentially jeopardize the integrity of public-key cryptography, which is the backbone of blockchain security.
A group of researchers from the Russian Quantum Center observed that the fact that blockchain security heavily relies on one-way mathematical functions — the ones that are easy to run, yet much more difficult to calculate in reverse. Such functions are used to both generate digital signatures and validate transactions on the ledger. A criminal equipped with a functional quantum device would be able to perform reverse calculations immensely faster, which would enable them to forge signatures, impersonate other users and gain access to their digital assets. In the context of mining, such a malicious actor could take over the process of updating the ledger, manipulate transaction history and double-spend coins.
The Russian researchers suggested that the architects of encrypted systems should start taking precautions against this threat immediately. One solution could be replacing conventional digital signatures with quantum-resistant cryptography — the kind of security algorithms specifically designed to withstand an attack from a sufficiently powerful quantum computer.
Researchers Del Rajan and Matt Visser from the Victoria University in New Zealand have proposed to forgo the use of quantum cryptography and leap straight to making blockchain a quantum-based system itself. Their model describes a blockchain based on qubits entangled not just in space, but also in time.