A framework for the analysis of the reliability of digital signatures for secure e-commerce

Digital signatures provide a valuable tool for secure internet trading by ensuring data authenticity and integrity and most importantly by enforcing commitment and non-repudiation for the transacting parties. The action of digitally signing has, however, several intrinsic weaknesses that introduce syntactic and semantic distance between a signer and a relying party. As a result, digitally signed messages cannot be fully trusted and hence nor can they be widely deployed in e-commerce applications. The syntactic robustness of digitally signed documents is evaluated by exploiting one key quantitative measure -structural informativenessand by comparing several qualitative characteristics of various alternative syntaxes. In this way, one is able to make decisions regarding the reliability of the syntax that will enhance the appropriateness of signed documents in specific internet-based e-commerce applications. At the same time, digitally signed documents must preserve their security characteristics and their formatting and layout capabilities in order to achieve an enhanced level of trust on the semantic part of communication and thus be trusted by e-commerce human users. Keywords— Security, Syntactic distance, Informativeness, Objectivity, Novelty, Redundancy, Trust