Privacy: Mixing

P2P Mixing

Centralized

Joseph Bonneau, Arvind Narayanan, Andrew Miller, Jeremy Clark, Joshua A. Kroll and Edward W. Felten

FC'14

TEE

Muoi Tran, Loi Luu, Min Suk Kang, Iddo Bentov, and Prateek Saxena

ACSAC '18

Decentralized

Maxwell, G, Bitcoin Forum (2013)

Limited scalability (e.g., only mix among 50 peers)

George Bissias, A Pinar Ozisik, Brian N Levine, and Marc Liberatore.

13th Workshop on Privacy in the Electronic Society

Long wait times (e.g., a few hours)

Jan Henrik Ziegeldorf, Fred Grossmann, Martin Henze, Nicolas Inden, Klaus Wehrle (RWTH Aachen University)

sMPC

2/3 of parties are honest

From CoinShuffle to ValueShuffle

Tim Ruffing (CISPA, Saarland University), Pedro Moreno-Sanchez (Purdue University), Aniket Kate (Purdue University)

ESORICS’14

Tim Ruffing (CISPA, Saarland University), Pedro Moreno-Sanchez (Purdue University), Aniket Kate (Purdue University)

Builds on the original DCnet protocol, and handles collisions and malicious peers

https://gyazo.com/70f350c1aaf85d5fdca4f6eb590c69c7

Provide a generic attack on P2P mixing protocols that exploits the implicit unfairness of a protocol allowing dishonest majority to break the anonymity of a peer.

Tim Ruffing (Saarland University) and Pedro Moreno-Sanchez (Purdue University)

FC'17 (Bitcoin Workshop)

Provides comprehensive privacy (payer anonymity, payee anonymity, and payment value privacy) by combining CoinJoin with Confidential Transactions and additionally Stealth Addresses

Requirement: Bitcoin's support of confidential transactions

Ethereum

Omer Shlomovits (KZen Research) and Istv´an Andr´as Seres (E¨otv¨os Lor´and University)

Threadhold ECDSA-based

https://gyazo.com/701978a636fbd2ca7f6e8826721329a4

MicroMix

Others

based on tees

Based on Semaphore