Generic Construction of Privacy-Preserving Optimistic Fair Exchange Protocol

Qingwen Guo, Yuzhao Cui, Xiaomeng Zuo, and Qiong Huang⁺

South China Agricultural University, Guangzhou 510642, China
{guoqingwen, yuzhaoc, zzxiaomengj}@ stu.scau.ecu.cn

qhuang @ scau.edu.cn

Abstract

Privacy-preserving optimistic fair exchange (P²OFE) is a kind of protocols which aim to solve the fairness problem in the exchange of digital signatures between two parties and in the meanwhile protect their privacy. In P²OFE, no one else including the semi-trusted third party in charge of arbitration can confirm an exchange even after resolving a dispute. In this paper we present a black-box construction of P²OFE based on a tag-based public key encryption scheme and a standard digital signature scheme. Our construction follows the ‘sign-then-encrypt’ paradigm, and is secure in the standard model. Our construction is generic and admits more instantiations of P²OFE.

Keywords: fair exchange, digital signature, privacy preserving, tag-based encryption

+: Corresponding author: Qiong Huang, qhuang@scau.edu.cn, 483Wushan Road, Tianhe District, Guangzhou 510642, P.R., Tel: +86-20-85285393

Journal of Internet Services and Information Security (JISIS), 7(2): 44-56, May 2017 [pdf]