Safety and security for fieldbus requirements

Abstract

There are many protocols for fail-safe communication that are either executed over a separate safety fieldbus or safely embedded in a regular fieldbus. Because of the growing risk of attacks against automation systems, security became an increasingly important issue. Safety and security measures apply different methods in order to achieve different goals. Their combination causes inevitable interactions. In this paper, an architecture for the combination of safety and security measures is presented. There the security measures are chosen such that the fault models of safety still hold and the security goals are reached without limitations. The interactions between the measures are analyzed with respect to safety and security criteria as well as efficiency.