Umbra: Privacy Preserving Token Transfers
- Ben DiFrancesco𝕏
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