Umbra: Privacy Preserving Token Transfers

Umbra: Privacy Preserving Token Transfers

Public transaction history in blockchains represents one of their key features which, alongside immutability, aim to provide an alternative to CeFi. However, this transparency comes at a price: privacy. As a result, different solutions have been proposed, that preserve privacy while maintaining all the other benefits of blockchain technology, but there currently isn't a one-size-fits-all answer to this problem. For example, zero knowledge proofs convey the validity of a transaction batch without sharing any other details, but the underlying arithmetic circuits are both complex as well as computational intensive. Umbra proposes a system that relies completely on elliptic curve cryptography, employing multiple private-public key pairs to achieve stealth payments.

We were joined by Ben DiFrancesco, founder & CEO of ScopeLift, to talk about Umbra's privacy preserving stealth token transfer system and if the need for privacy on blockchains outweighs any implicit UX frictions.

Topics:

  • Ben’s background
  • Umbra's mission
  • How Umbra works
  • Non-interactive key distribution
  • Potential solutions (& trade-offs) for Umbra's computational intensity
  • Generating private-public key pairs by the Umbra smart contract
  • User experience (UX) for senders and receivers
  • Fee structure for deterring griefing attacks
  • How Umbra works for ERC20 tokens & NFTs
  • Privacy preserving withdrawals from stealth addresses
  • Privacy vs. UX friction
  • Smart wallets & account abstraction
  • Prioritising privacy

Links:

Host:Friederike Ernst