Mahdi Sedaghat

Mahdi Sedaghat

Postdoctoral Researcher @ COSIC (KU Leuven) | PhD in Cryptography | Freelance

Zero-Knowledge proofs: Applications to Blockchain

Date:

You can find the slides in this link.

  • Web3 vs. Web2 Challenges:
    • Web3 has scalability and user onboarding issues compared to Web2.
    • Limited transaction throughput in blockchains like Bitcoin and Ethereum compared to payment systems like Visa and Mastercard.
    • Web3 has 100 million active crypto wallets, far fewer than billions of Web2 accounts.
  • Ethereum Rollup-Centric Roadmap:
    • Rollups execute transactions off-chain and post them on-chain to improve scalability.
    • Comparison between Optimistic Rollups and zk-Rollups:
      • Optimistic Rollups: Simpler technology, rely on economic incentives, 1-2 weeks withdrawal period.
      • zk-Rollups: Higher complexity, cryptographic certainty, nearly instant withdrawals.
  • Cryptographic Tools in Blockchain:
    • Examples: Verifiable Secret Sharing, Threshold Cryptography, Multi-Party Computation, Digital Signatures, Zero-Knowledge Proofs, and more.
  • Zero-Knowledge Proofs (ZKPs):
    • Core properties:
      • Completeness: An honest prover can convince a verifier.
      • Soundness: A dishonest prover cannot convince a verifier without valid proof.
      • Zero-Knowledge: No information beyond proof validity is leaked.
    • zk-SNARKs are a practical form of ZKPs with efficient verification and small proof size.
  • Applications of ZKPs in 2024:
    • Payments, DeFi, Cross-chain transfers, zkML/AI, Gaming, Identity & Wallets, and more.
    • Specific tools and projects:
      • zkLogin: Simplifies Web3 onboarding using SNARKs combined with OAuth providers like Google and Facebook.
      • Prover networks for verifiable computation and decentralized applications.
  • zkLogin: A Case Study
    • Combines OAuth with zk-SNARKs for non-custodial, privacy-preserving authentication.
    • Uses JWT (JSON Web Token) as a key alternative, signed by providers like Google or Facebook.
    • Offers single-click, user-friendly onboarding with invisible wallets and 2FA support.
  • Conclusion: Zero-knowledge proofs are key to addressing Web3 scalability, privacy, and user experience challenges.