Fair exchange with a semi-trusted third party (extended abstract)
Proceedings of the 4th ACM conference on Computer and communications security
Efficient verifiable encryption (and fair exchange) of digital signatures
CCS '99 Proceedings of the 6th ACM conference on Computer and communications security
Optimistic Fair Exchange with Transparent Signature Recovery
FC '01 Proceedings of the 5th International Conference on Financial Cryptography
Supporting fair exchange in mobile environments
Mobile Networks and Applications - Security in mobile computing environments
Optimistic fair exchange of digital signatures
IEEE Journal on Selected Areas in Communications
Hi-index | 0.00 |
In 2005, Zhang et al. proposed a novel fair digital signature exchange protocol that can impose a penalty on the misbehaving party. However, we have discovered a weakness concerning the fairness aspect of the protocol which will occur when an initiator tries to exchange the signature of the same document to others again. That is, the latter exchange partner can obtain the initiator's valid signature with the help of the previous exchange partner without completing the protocol, and therefore the protocol is not fair enough. In this paper, the reason for the occurrence of the unfair exchange is discussed, and an improvement to remove the weakness is proposed.