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P2OFE: Privacy-preserving optimistic fair exchange of digital signatures

Journal Article


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Abstract


  • How to sign an electronic contract online between two parties

    (say Alice and Bob) in a fair manner is an interesting problem, and has

    been studied for a long time. Optimistic Fair Exchange (OFE) is an

    efficient solution to this problem, in which a semi-trusted third party

    named arbitrator is called in to resolve a dispute if there is one during an

    exchange between Alice and Bob. Recently, several extensions of OFE,

    such as Ambiguous OFE (AOFE) and Perfect AOFE (PAOFE), have

    been proposed to protect the privacy of the exchanging parties. These

    variants prevent any outsider including the arbitrator from telling which

    parties are involved in the exchange of signatures before the exchange

    completes.

    However, in PAOFE, AOFE, and all the current work on OFE, the

    arbitrator can always learn the signer’s signature at (or before) the end

    of a resolution, which is undesirable in some important applications,

    for example, signing a contract between two parties which do not wish

    others to find out even when there is a dispute that needs a resolution by

    the arbitrator. In this work, we introduce a new notion called Privacy-

    Preserving Optimistic Fair Exchange (P2OFE), in which other than Alice

    and Bob, no one else, including the arbitrator, can collect any evidence

    about an exchange between them even after the resolution of a dispute.

    We formally define P2OFE and propose a security model. We also propose

    a concrete and efficient construction of P2OFE, and prove its security

    based on the Strong Diffie-Helllman and Decision Linear assumptions in

    the standard model.

UOW Authors


  •   Huang, Qiong (external author)
  •   Wong, Duncan S. (external author)
  •   Susilo, Willy

Publication Date


  • 2014

Citation


  • Huang, Q., Wong, D. S. & Susilo, W. (2014). P2OFE: Privacy-preserving optimistic fair exchange of digital signatures. Lecture Notes in Computer Science, 8366 367-384.

Scopus Eid


  • 2-s2.0-84901263178

Ro Full-text Url


  • http://ro.uow.edu.au/cgi/viewcontent.cgi?article=2930&context=eispapers

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers/1921

Has Global Citation Frequency


Number Of Pages


  • 17

Start Page


  • 367

End Page


  • 384

Volume


  • 8366

Place Of Publication


  • Germany

Abstract


  • How to sign an electronic contract online between two parties

    (say Alice and Bob) in a fair manner is an interesting problem, and has

    been studied for a long time. Optimistic Fair Exchange (OFE) is an

    efficient solution to this problem, in which a semi-trusted third party

    named arbitrator is called in to resolve a dispute if there is one during an

    exchange between Alice and Bob. Recently, several extensions of OFE,

    such as Ambiguous OFE (AOFE) and Perfect AOFE (PAOFE), have

    been proposed to protect the privacy of the exchanging parties. These

    variants prevent any outsider including the arbitrator from telling which

    parties are involved in the exchange of signatures before the exchange

    completes.

    However, in PAOFE, AOFE, and all the current work on OFE, the

    arbitrator can always learn the signer’s signature at (or before) the end

    of a resolution, which is undesirable in some important applications,

    for example, signing a contract between two parties which do not wish

    others to find out even when there is a dispute that needs a resolution by

    the arbitrator. In this work, we introduce a new notion called Privacy-

    Preserving Optimistic Fair Exchange (P2OFE), in which other than Alice

    and Bob, no one else, including the arbitrator, can collect any evidence

    about an exchange between them even after the resolution of a dispute.

    We formally define P2OFE and propose a security model. We also propose

    a concrete and efficient construction of P2OFE, and prove its security

    based on the Strong Diffie-Helllman and Decision Linear assumptions in

    the standard model.

UOW Authors


  •   Huang, Qiong (external author)
  •   Wong, Duncan S. (external author)
  •   Susilo, Willy

Publication Date


  • 2014

Citation


  • Huang, Q., Wong, D. S. & Susilo, W. (2014). P2OFE: Privacy-preserving optimistic fair exchange of digital signatures. Lecture Notes in Computer Science, 8366 367-384.

Scopus Eid


  • 2-s2.0-84901263178

Ro Full-text Url


  • http://ro.uow.edu.au/cgi/viewcontent.cgi?article=2930&context=eispapers

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers/1921

Has Global Citation Frequency


Number Of Pages


  • 17

Start Page


  • 367

End Page


  • 384

Volume


  • 8366

Place Of Publication


  • Germany