Lockmix: a secure and privacy-preserving mix service for Bitcoin anonymity

Bitcoin has attracted considerable attention from governments, banks, as well as researchers. However, Bitcoin is not a completely anonymous system. All transaction information in the Bitcoin system is published on the network and can be used to reveal the identity of the user by transaction correlation analysis. In this paper, a secure and privacy-preserving mix service for Bitcoin anonymity, Lockmix, is proposed. Lockmix introduces mix servers to provide a mix service for the user by using blind signature and multi-signature schemes to prevent attackers from linking the input address with the output address. Lockmix provides anonymity, scalability, accountability, Bitcoin compatibility and anti-theft. Lockmix has been implemented on a Bitcoin test network, and experiments show that our solution is efficient.

[1]  Andrew Miller,et al.  Discovering Bitcoin ’ s Public Topology and Influential Nodes , 2015 .

[2]  Klaus Wehrle,et al.  CoinParty: Secure Multi-Party Mixing of Bitcoins , 2015, CODASPY.

[3]  David Chaum,et al.  Blind Signatures for Untraceable Payments , 1982, CRYPTO.

[4]  Patrick D. McDaniel,et al.  An Analysis of Anonymity in Bitcoin Using P2P Network Traffic , 2014, Financial Cryptography.

[5]  Matthew Green,et al.  Zerocoin: Anonymous Distributed E-Cash from Bitcoin , 2013, 2013 IEEE Symposium on Security and Privacy.

[6]  Nick Mathewson,et al.  Tor: The Second-Generation Onion Router , 2004, USENIX Security Symposium.

[7]  Luke Valenta,et al.  Blindcoin: Blinded, Accountable Mixes for Bitcoin , 2015, Financial Cryptography Workshops.

[8]  Georg Fuchsbauer,et al.  Automorphic Signatures in Bilinear Groups and an Application to Round-Optimal Blind Signatures , 2009, IACR Cryptol. ePrint Arch..

[9]  Mauro Conti,et al.  A Survey on Security and Privacy Issues of Bitcoin , 2017, IEEE Communications Surveys & Tutorials.

[10]  Jeremy Clark,et al.  Mixcoin: Anonymity for Bitcoin with Accountable Mixes , 2014, Financial Cryptography.

[11]  Satoshi Nakamoto.  Bitcoin : A Peer-to-Peer Electronic Cash System , 2009 .

[12]  Mihir Bellare,et al.  Identity-Based Multi-signatures from RSA , 2007, CT-RSA.

[13]  Jianping Yu,et al.  A Blind-Mixing Scheme for Bitcoin based on an Elliptic Curve Cryptography Blind Digital Signature Algorithm , 2015, ArXiv.

[14]  Brian W. Kernighan,et al.  The Go Programming Language , 2015 .

[15]  Pedro Moreno-Sanchez,et al.  P2P Mixing and Unlinkable Bitcoin Transactions , 2017, NDSS.

[16]  Adi Shamir,et al.  Quantitative Analysis of the Full Bitcoin Transaction Graph , 2013, Financial Cryptography.

[17]  Fergal Reid,et al.  An Analysis of Anonymity in the Bitcoin System , 2011, PASSAT 2011.

[18]  Mohamed Ali Kâafar,et al.  Digging into Anonymous Traffic: A Deep Analysis of the Tor Anonymizing Network , 2010, 2010 Fourth International Conference on Network and System Security.

[19]  Eli Ben-Sasson,et al.  Succinct Non-Interactive Zero Knowledge for a von Neumann Architecture , 2014, USENIX Security Symposium.

[20]  Nicolas van Saberhagen.  CryptoNote v 2.0 , 2013 .

[21]  L. Harn.  Group-oriented (t, n) threshold digital signature scheme and digital multisignature , 1994 .

[22]  Eli Ben-Sasson,et al.  Zerocash: Decentralized Anonymous Payments from Bitcoin , 2014, 2014 IEEE Symposium on Security and Privacy.