Threshold-oriented optimistic fair exchange

Yang Wang, Man Ho Allen Au, Joseph K Liu, Tsz Hon Yuen, Willy Susilo

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

3 Citations (Scopus)


Fair exchange protocol aims to allow two parties to exchange digital items in a fair manner. It is well-known that fairness can only be achieved with the help of a trusted third party, usually referred to as arbitrator. A fair exchange protocol is optimistic if the arbitrator is not involved in the normal execution of the fair exchange process. That is, its presence is necessary only when one of the exchanging parties is dishonest. Traditionally, the items being exchanged are digital signatures. In this paper, we consider the items to be threshold signatures. Specifically, the signatures are created by a subset of legitimate signers instead of a single signer. We define a security model for this new notion, and provide an concrete instantiation. Our instantiation can be proven secure in the random oracle model. Our definition covers the case when the item being exchanged is a secret key of an identity-based encryption where the master secret key is split amongst a set of authorities.
Original languageEnglish
Title of host publicationProceedings of the 7th International Conference on Network and System Security (NSS 2013)
EditorsJavier Lopez, Xinyi Huang, Ravi Sandhu
Place of PublicationHeidelberg Germany
Pages424 - 438
Number of pages15
ISBN (Print)9783642386305
Publication statusPublished - 2013
Externally publishedYes
EventInternational Conference on Network and System Security 2013 - Madrid, Spain
Duration: 3 Jun 20134 Jun 2013
Conference number: 7th


ConferenceInternational Conference on Network and System Security 2013
Abbreviated titleNSS 2013
OtherNSS 2013 will be co-located with The 6th International Conference on Biometrics (ICB 2013)
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