Filling the gap between Requirements Engineering and Public Key/Trust Management Infrastructures

The last years have seen a major interest in designing and deploying trust management and public key infrastructures. Yet, it is still far from clear how one can pass from the organization and system requirements to the actual credentials and attribution of permissions in the PKI infrastructure. Our goal in this paper is filling this gap. We propose a formal framework for modeling and analyzing security and trust requirements, that extends the Tropos methodology for early requirements modeling. The key intuition that underlies our work is the identification of distinct roles for actors that manipulate resources, accomplish goals or execute tasks, and actors that own or permit usage of resources or goals. The paper also presents a simple case study and a PKI/trust management implementation.