Identity-Based Optimistic Fair Exchange with Transparent Signature Recovery
نویسندگان
چکیده
In this paper, we propose a new practical fair exchange protocol allowing the exchange of an electronic item against a signature. The protocol is based on the Guillou-Quisquater scheme and assumes the existence of a trusted third party that is involved in the protocol only in the setup phase and when one of the parties does not follow the protocol or some technical problems occur during the execution of the protocol. The interesting feature of the protocol is the low communication and computational costs required by the parties. Moreover, in case of problems during the main protocol, the trusted third party acts transparently.
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