posted on 2023-11-29, 18:23authored byKarl Wüst, Kari Kostiainen, Noah Delius, Srdjan Capkun
Due to the popularity of blockchain-based cryptocurrencies, the increasing digitalization of payments, and the constantly reducing role of cash in society, central banks have shown an increased interest in deploying central bank digital currencies (CBDCs) that could serve as a digital cash-equivalent. While most recent research on CBDCs focuses on blockchain technology, it is not clear that this choice of technology provides the optimal solution. In particular, the centralized trust model of a CBDC offers opportunities for different designs. In this paper, we depart from blockchain designs and instead build on ideas from traditional e-cash schemes. We propose a new style of building digital currencies that combines the transaction processing model of e-cash with an account-based fund management model. We argue that such a style of building digital currencies is especially well-suited to CBDCs. We also design the first such digital currency system, called Platypus, that provides strong privacy, high scalability, and expressive but simple regulation, which are all critical features for a CBDC. Platypus achieves these properties by adapting techniques similar to those used in anonymous blockchain cryptocurrencies like Zcash to fit our account model and applying them to the e-cash context.
History
Preferred Citation
Karl Wüst, Kari Kostiainen, Noah Delius and Srdjan Capkun. Platypus: A Central Bank Digital Currency with Unlinkable Transactions and Privacy-Preserving Regulation. In: ACM Conference on Computer and Communications Security (CCS). 2022.
Primary Research Area
Algorithmic Foundations and Cryptography
Name of Conference
ACM Conference on Computer and Communications Security (CCS)
Legacy Posted Date
2022-10-13
Open Access Type
Green
BibTeX
@inproceedings{cispa_all_3823,
title = "Platypus: A Central Bank Digital Currency with Unlinkable Transactions and Privacy-Preserving Regulation",
author = "Wüst, Karl and Kostiainen, Kari and Delius, Noah and Capkun, Srdjan",
booktitle="{ACM Conference on Computer and Communications Security (CCS)}",
year="2022",
}