HKU Coin: Towards Decentralized Privacy-Preserving Cryptocurrency with Accountability

PI: Dr. Allen Au, HKU 

Project Abstract: 

Blockchain-based cryptocurrencies such as Bitcoin provide a way to construct decentralized payment systems without the need of any trusted parties. However, these cryptocurrencies inherent the transparent feature of blockchain and thus lack privacy.  To tackle this problem, considerable efforts have been devoted to the development of privacy-preserving cryptocurrencies.  Examples, including Monero and Zcash, employ advanced cryptographic primitives to provide user privacy. However, strong privacy is a double-edge sword.  These cryptocurrencies could be abused and are often associated with illegal activities such as blackmailing or money laundering. Indeed, the strong privacy guarantee makes it challenging for auditing, as the accountability and anonymity are often viewed as contradicting.  Considering accountability is essential in many real-world, a decentralized cryptocurrency supporting privacy and accountability is desired.  Existing effort provides a balance between privacy and accountability, at the cost of additionally trusted third party, which violates the intrinsic property of decentralization, or only support fairly limited auditing operations.

In this project, we plan to develop new mechanisms to support various compliance measures while maintaining privacy.  We aim to construct the first decentralized cryptocurrency capable of protecting the privacy of all participants and simultaneously offering full-fledged accountability.