Blindly Signed Contracts: Anonymous On-Blockchain and Off-Blockchain Bitcoin Transactions

Ethan Heilman; Foteini Baldimtsi; Sharon Goldberg

Paper 2016/056

Blindly Signed Contracts: Anonymous On-Blockchain and Off-Blockchain Bitcoin Transactions

Ethan Heilman, Foteini Baldimtsi, and Sharon Goldberg

Abstract

Although Bitcoin is often perceived to be an anonymous currency, research has shown that a user's Bitcoin transactions can be linked to compromise the user's anonymity. We present solutions to the anonymity problem for both transactions on Bitcoin's blockchain and off the blockchain (in so called micropayment channel networks). We use an untrusted third party to issue anonymous vouchers which users redeem for Bitcoin. Blind signatures and Bitcoin transaction contracts (aka smart contracts) ensure the anonymity and fairness during the bitcoin $\leftrightarrow$ voucher exchange. Our schemes are practical, secure and anonymous.

Metadata

Available format(s): PDF
Category: Applications
Publication info: Published elsewhere. 3rd Workshop on Bitcoin and Blockchain Research
Keywords: bitcoin blockchain smart contracts blind signatures anonymity
Contact author(s): ethan r heilman @ gmail com
History: 2016-03-02: revised; 2016-01-25: received; See all versions
Short URL: https://ia.cr/2016/056
License: CC BY

BibTeX

@misc{cryptoeprint:2016/056,
      author = {Ethan Heilman and Foteini Baldimtsi and Sharon Goldberg},
      title = {Blindly Signed Contracts: Anonymous On-Blockchain and Off-Blockchain Bitcoin Transactions},
      howpublished = {Cryptology {ePrint} Archive, Paper 2016/056},
      year = {2016},
      url = {https://eprint.iacr.org/2016/056}
}