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The construction of ambiguous optimistic fair exchange from designated confirmer signature without random oracles

Journal Article


Abstract


  • Ambiguous Optimistic Fair Exchange (AOFE), introduced by Huang et al. in ASIACRYPT

    2008, is an extension of OFE that enhances the fairness of the two communicating parties

    in the exchange of signatures. The first scheme was proven secure without random oracles

    while its partial signature contains dozens of group elements. Recently, interactive AOFE

    was introduced and the construction is more practical, where a partial signature only contains

    three group elements. It is based on the existence of Designated Confirmer Signature

    (DCS) with a special property where one is able to sample a confirmer signature efficiently

    from a signer’s signature space. Nevertheless, we note that there are only a few DCS

    schemes that have this special property. Security of the interactive AOFE construction

    relies on the q-Computational and Decisional Hidden Strong Diffie-Hellman assumptions.

    In this paper, we propose a new construction of interactive AOFE from DCS, where the

    underlying DCS is standard and does not require any special property. We also propose a

    new DCS construction. By applying our transformation from DCS to interactive AOFE, we

    build a concrete interactive AOFE which is secure under more standard number-theoretic

    assumptions, namely Strong Diffie-Hellman and Decision Linear assumptions, without random

    oracles. A partial signature of the interactive AOFE contains six group elements, while

    a full signature contains two only.

UOW Authors


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

Publication Date


  • 2013

Citation


  • Huang, Q., Wong, D. S. & Susilo, W. (2013). The construction of ambiguous optimistic fair exchange from designated confirmer signature without random oracles. Information Sciences, 228 222-238.

Scopus Eid


  • 2-s2.0-84873152844

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers/205

Number Of Pages


  • 16

Start Page


  • 222

End Page


  • 238

Volume


  • 228

Abstract


  • Ambiguous Optimistic Fair Exchange (AOFE), introduced by Huang et al. in ASIACRYPT

    2008, is an extension of OFE that enhances the fairness of the two communicating parties

    in the exchange of signatures. The first scheme was proven secure without random oracles

    while its partial signature contains dozens of group elements. Recently, interactive AOFE

    was introduced and the construction is more practical, where a partial signature only contains

    three group elements. It is based on the existence of Designated Confirmer Signature

    (DCS) with a special property where one is able to sample a confirmer signature efficiently

    from a signer’s signature space. Nevertheless, we note that there are only a few DCS

    schemes that have this special property. Security of the interactive AOFE construction

    relies on the q-Computational and Decisional Hidden Strong Diffie-Hellman assumptions.

    In this paper, we propose a new construction of interactive AOFE from DCS, where the

    underlying DCS is standard and does not require any special property. We also propose a

    new DCS construction. By applying our transformation from DCS to interactive AOFE, we

    build a concrete interactive AOFE which is secure under more standard number-theoretic

    assumptions, namely Strong Diffie-Hellman and Decision Linear assumptions, without random

    oracles. A partial signature of the interactive AOFE contains six group elements, while

    a full signature contains two only.

UOW Authors


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

Publication Date


  • 2013

Citation


  • Huang, Q., Wong, D. S. & Susilo, W. (2013). The construction of ambiguous optimistic fair exchange from designated confirmer signature without random oracles. Information Sciences, 228 222-238.

Scopus Eid


  • 2-s2.0-84873152844

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers/205

Number Of Pages


  • 16

Start Page


  • 222

End Page


  • 238

Volume


  • 228