Abstract: A method to generate Immutable Audit logs (IAL) using related computer means and/or computer programs. This method and system processes audit information by cryptographic means generating one immutable digital chains that will contain at least the audit information split among the links and optionally encrypted, and this immutable digital chain is stored in a massive storage media. Each immutable digital chain is generated by including at every link at least the data resulting to apply a MAC function using a secret session key K over the result of information at current link concatenated with a previous link MAC value. The method proposes adding specific links to said immutable digital chain at regular defined intervals (‘Metronome Entry’) that contain at least a timestamp and the data resulting to apply a digital signature using a private key that is always kept secret over the metronome timestamp concatenated with previous link results.

Abstract: This method and system uses means of cryptographic techniques reproducing the functionality of a continuous roll of paper. The audit logs can contain any kind of data information (text, voice, video, actions . . . ) and this invention provides full guarantees for data integrity: order of data logged can't be altered and content can't be modified neither added nor deleted without detection. Authenticity of the IAL is guaranteed by the use of digital signatures. Confidentiality is also guaranteed by encrypting the data information. By using PKI encryption the invention also guarantees that only authorized auditors will be able to check the integrity of the IAL and access to the data content.