Post-quantum blockchains | Valeria Nikolaenko

TL;DR

Post-Quantum blockchains face threats from Quantum adversaries, who can forge digital signatures and disrupt consensus algorithms. However, there are ways to protect blockchains using new post-Quantum cryptography.

Transcript

thank you very much for the introduction uh yeah my name is Valeria you can call me Lara that's less formal I prefer that um if you're cool with that so today we're going to discuss post Quantum blockchains Quantum Computing this is an exciting topic I know it was prompted by your questions so you get the message here the more technical questions y... Read More

Key Insights

• 💻 Quantum computers pose a significant threat to blockchains by exploiting vulnerabilities in digital signatures and consensus algorithms.
• ⛓️ Quantum adversaries can forge digital signatures, steal funds, and disrupt consensus by creating alternative chains in proof-of-stake systems.
• 😥 Quantum computing progress is rapid, potentially reaching a point where it can break current cryptography in around 15 years.
• 👊 Post-quantum cryptography offers a solution to protect blockchains using new signature schemes that are resistant to quantum attacks.
• 🏣 Introducing hashing and post-quantum signature alternatives can help defend against quantum adversaries and ensure the security of blockchains in a post-quantum era.
• 😘 The future may see quantum computers in space, taking advantage of the natural cooling and lack of vibrations to maintain the necessary low temperatures for quantum computing.

Questions & Answers

Q: How does quantum computing pose a threat to blockchains?

Quantum adversaries can forge digital signatures, allowing them to steal funds and disrupt consensus algorithms, leading to potential double-spending and loss of user trust in the blockchain.

Q: Can existing digital signatures be broken by quantum computers?

Yes, all current digital signature schemes, such as BLS, ECDSA, and DSA, are susceptible to quantum attacks. Quantum computers can efficiently forge these signatures, compromising the security of blockchains.

Q: Is there hope for post-quantum cryptography to defend against quantum attacks?

Yes, there is ongoing research and development of post-quantum cryptography. Institutions like NIST are standardizing new signature schemes that are resistant to quantum attacks. However, these new signatures can be computationally expensive and require larger key and signature sizes.

Q: How can blockchains defend against quantum attacks?

Blockchain developers can introduce hashing to protect secret keys and use post-quantum signature alternatives to ensure security in a post-quantum world. Validators can also sign blocks infrequently using post-quantum signatures to protect consensus against quantum adversaries.

Summary & Key Takeaways

• Post-Quantum blockchains are at risk from Quantum adversaries, who can forge digital signatures, steal funds, and disrupt consensus algorithms.

• Quantum computing progress is rapid, with the number of qubits doubling each year. In 15 years, quantum computers might have the capability to break current cryptography.

• To defend against Quantum attacks, blockchain developers can introduce hashing to protect secret keys and implement post-Quantum signature alternatives for validators.