Symmetric Cryptography Protocol for Signing and Authenticating Digital Documents

The fast growth of technology and the demands of contemporary globalization have meant that most organizations use electronic means for communication and formalization of documents. One of the main problems faced by reviewers is recognizing counterfeit documents. The electronic signature of documents is a preliminary solution to the problem. In our research we are interested in developing a web service that allows to sign documents and verify their authenticity. To protect this web service against malicious activity there are aspects of computer security that must be considered such as steganography, cryptography and security protocols. In this article we introduce a security protocol using symmetric cryptography scheme in order to sign and authenticate digital documents. We have verified formally this protocol and found out that it provides the fourth level of authentication according to Lowe’s hierarchy. In addition, we also address security aspects that must be taken into account to avoid attacks in these kinds of applications and some implementations we are developing.