Process for providing non repudiation of receipt (NRR) in an electronic transaction environment

A Non-Receipt Repudiation protocol between the emitter, the receiver and a Trusted Third Party (TTP) which is based on the transmission to the receiver of a first envelope which comprises an encrypted version of the message or document , a hash function of said message, and a Validation Certificate (VC) creating an unique link between said message M, said key K and said emitter. More specifically, the protocol involves the steps of transmitting a first envelope from the emitter to the receiver, said first envelope including a first, a second, a third, a fourth and a fifth element. The first element consists of an optional identifier (H1). The second element consists of an encrypted form of said document or message ÄMÜk. The third element consists of the hashing of said message M. The fourth element is formed by ÄK, h(M)Ü encrypted with the public key of the TTP. A fifth element consists of a Validation Certificate (VC) consisting of a signature of said emitter which is used for creating an unambiguous link between the original message M and the key K chosen and used by the originator for encrypting this message before the latter is transmitted to the recipient.