Non-repudiation with mandatory proof of receipt

Abstract

Non-repudiation allows an exchange of data between two principals in such a manner that the principals cannot subsequently deny their participation in the exchange. Current non-repudiation schemes, while providing a mandatory proof of origin service, generally provide only discretionary proof of receipt since it is difficult to enforce the return of the proof of receipt by the recipient. In this paper a new scheme for achieving mandatory mutual non-repudiation is proposed, encompassing both mandatory proof of origin and mandatory proof of receipt. The fundamental feature of the scheme is that the proofs of origin and receipt are not exchanged until both principals have submitted their digitally signed evidence to a trusted third party intermediary. This ensures that if the non-repudiation protocol is not completed, neither principal can gain from the exchange. An added advantage is that the process of dispute arbitration is considerably simplified since a small number of rules are required to decide whether an alleged data exchange took place.