Efficient Fair Contract Signing Protocol from Bilinear Pairings

This paper presents a new fair contract signing protocol between two distrusted parties, which is based on a signature scheme, a verifiable and recoverable encrypted signature (VRES) from bilinear pairings. The protocol employs an off-line trusted third party (TTP), which participates in the protocol execution only in exceptional circumstances and which involvement in the protocol is invisible. It can also prevent the TTP from gaining the content of the contract. The protocol guarantees strong fairness and the analysis shows that it has less computation overhead and is more efficient compared with the other related protocol.