Formal Analysis and Improvement of iKP Protocol

Accountability and fairness are two important requirements of secure e-payment protocols, which can provide evidences to solving disputes in e-commerce and keep sure that each participant in protocol achieves fairness in an unreliable channel. Therefore logic formal analysis in these two aspects has become very important. In this paper, we have formally analyzed iKP protocol by extended Kailar logic and have found that iKP do not satisfy these two requirements,then, we proposed an improved protocol. The new protocol we present is capable to support goods and services delivery as well as payment, which the original iKP do not take care of goods and services delivery. By referring to a formal semantics of extended Kailar logic we can prove that the new protocol can achieve fairness and accountability through appropriate modifications.