As Bitcoin researchers debate how blockchain can be strengthened against the potentially disruptive threats that quantum computers may pose in the future, ‘hash-based signatures’ stand out as an important potential solution.
This is considered one of the biggest security risks to the blockchain ecosystem, as quantum computers have the potential to break classical cryptography.
Quantum computers can solve certain mathematical problems many times faster than classical computers thanks to the advantages provided by quantum mechanics. This means that the cryptographic structures that form the basis of blockchains such as Bitcoin could be compromised in the future.
In a new study published on December 5, Blockstream researchers Mikhail Kudinov and Jonas Nick looked at various methods that could be implemented to make the $1.8 trillion Bitcoin network more resilient to quantum attacks. The pair argued that hash-based signatures are one of the most attractive options because their security is based on the hash function already used in Bitcoin’s design.
“These schematics have undergone extensive analysis through NIST’s post-quantum standardization process, increasing confidence in their robustness,” said Kudinov, who published a study on email lists of Bitcoin developers. The National Institute of Standards and Technology (NIST), a U.S. government agency, is known for setting cybersecurity standards used around the world.
Scholars have long disagreed about when quantum computers threaten Bitcoin, but recent developments have reignited the debate. In February, Microsoft announced a new chip that it claims will solve the scaling problem of quantum computers. In October, Google published research showing that quantum computing is much closer to real-world applications.
Pierre-Luc Dallaire Demers, a scientist at the University of Calgary, says that at the current rate of progress, Bitcoin could become vulnerable to quantum computer threats within the next five to 10 years. However, Ethereum co-founder Vitalik Buterin is concerned about an earlier timeline. Buterin said Ethereum’s security model could be compromised even before the 2028 US presidential election.
Hash-based signatures rely on hash functions and are considered mathematically resistant to quantum attacks. Unlike Bitcoin’s public-key cryptography, hash functions are much more resistant to quantum algorithms like Scholl. Furthermore, the output of the hash function can be extended to render the brute force search capabilities of quantum computers meaningless.
However, it is not yet clear how this technique will be applied to Bitcoin. Key issues such as verification costs, whether multiple hash-based signature standards will be supported, and whether the entire blockchain history is required for transaction verification are still being debated among developers.
*This is not investment advice.
