anonymisation; classification; compliance; crypto-asset; digital forensics; zero-knowledge proofs
Abstract :
[en] The role played by decentralised services in the obfuscation of crypto-asset transactions performed on transparent blockchains has increasingly captured the attention of regulators. This is exemplified by the headlines about the U.S. Treasury's sanctions on the Ethereum-based mixer Tornado Cash. Yet, despite the existing controversies on the use of mixers, the different functionalities of these information systems with an inherent dark side remain to be explored by the literature. So far, contributions primarily encompass technical works and studies that focus on the Bitcoin ecosystem. This paper puts forward a multi-layer taxonomy of the smart-contract-based-and, therefore, functionally richer family of mixers on Ethereum. Our proposed taxonomy is grounded on (1) a review of existing literature, (2) an analysis of mixers' project documentation, (3) their corresponding smart contracts, and (4) expert interviews. Our evaluation included the application of the taxonomy to two mixers - RAILGUN and zkBob. The taxonomy represents a valuable tool for law enforcement, regulators, and other stakeholders to explore critical properties affecting compliance and use of Ethereum-based mixers.
Research center :
Interdisciplinary Centre for Security, Reliability and Trust (SnT) > FINATRAX - Digital Financial Services and Cross-organizational Digital Transformations NCER-FT - FinTech National Centre of Excellence in Research [LU]
Disciplines :
Engineering, computing & technology: Multidisciplinary, general & others Computer science Management information systems
Author, co-author :
BARBEREAU, Tom Josua ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > FINATRAX
ERMOLAEV, Egor ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > FINATRAX
BRENNECKE, Martin ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > FINATRAX
HARTWICH, Eduard ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > FINATRAX
SEDLMEIR, Johannes ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > FINATRAX
External co-authors :
no
Language :
English
Title :
Beyond a Fistful of Tumblers: Toward a Taxonomy of Ethereum-based Mixers
Publication date :
10 December 2023
Event name :
Proceedings of the 44th International Conference on Information Systems (ICIS), Hyderabad, India
FNR - Fonds National de la Recherche [LU] FNR - Luxembourg National Research Fund [LU]
Funding number :
13342933; 14783405; 16326754
Funding text :
This research was funded by the Luxembourg National Research Fund (FNR) and PayPal PEARL (grant reference 13342933) as well as by the FNR in the FiReSPArX (grant reference 14783405) and PABLO (grant reference 16326754) projects. For the purpose of open access, the authors have applied a Creative CommonsAttribution 4.0 International (CC BY 4.0) license to any author accepted manuscript version arising from this submission.
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