Optimistic fair exchange in a multi-user setting

Yevgeniy Dodis, Pil Joong Lee, Dae Hyun Yum

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

This paper addresses the security of optimistic fair exchange in a multi-user setting. While the security of public key encryption and public key signature schemes in a single-user setting guarantees the security in a multi-user setting, we show that the situation is different in the optimistic fair exchange. First, we show how to break, in the multi-user setting, an optimistic fair exchange scheme provably secure in the single-user setting. This example separates the security of optimistic fair exchange between the single-user setting and the multi-user setting. We then define the formal security model of optimistic fair exchange in the multi-user setting, which is the first complete security model of optimistic fair exchange in the multi-user setting. We prove the existence of a generic construction meeting our multi-user security based on one-way functions in the random oracle model and trapdoor one-way permutations in the standard model. Finally, we revisit two well-known methodologies of optimistic fair exchange, which are based on the verifiably encrypted signature and the sequential two-party multisignature, respectively. Our result shows that these paradigms remain valid in the multi-user setting.

Original languageEnglish (US)
Title of host publicationPublic Key Cryptography - PKC 2007 - 10th International Conference on Practice and Theory in Public-Key Cryptography, Proceedings
PublisherSpringer Verlag
Pages118-133
Number of pages16
ISBN (Print)9783540716761
DOIs
StatePublished - 2007
Event10th International Conference on Theory and Practice in Public-Key Cryptography, PKC 2007 - Beijing, China
Duration: Apr 16 2007Apr 20 2007

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
Volume4450 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349

Other

Other10th International Conference on Theory and Practice in Public-Key Cryptography, PKC 2007
CountryChina
CityBeijing
Period4/16/074/20/07

ASJC Scopus subject areas

  • Theoretical Computer Science
  • Computer Science(all)

Fingerprint Dive into the research topics of 'Optimistic fair exchange in a multi-user setting'. Together they form a unique fingerprint.

  • Cite this

    Dodis, Y., Lee, P. J., & Yum, D. H. (2007). Optimistic fair exchange in a multi-user setting. In Public Key Cryptography - PKC 2007 - 10th International Conference on Practice and Theory in Public-Key Cryptography, Proceedings (pp. 118-133). (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics); Vol. 4450 LNCS). Springer Verlag. https://doi.org/10.1007/978-3-540-71677-8_9