A framework for a secure embedded filtering connector for multi-criticality systronic systems

Safety Critical systems are those systems which may endanger human lives if a failure occurs. This is the case, for example, in avionics and in modern vehicles. Security critical systems contains data or knowledge that should stay confidential. Depending on the impact of such revelation, the security level requested varies. In today´s modern vehicles, many safety-critical subsystems are also security critical. These subsystems are usually interconnected through a network, each subsystem having different criticality levels. Problems come when low criticality (e.g. a multimedia application) subsystems need to exchange information with high criticality ones. If nothing is done, the low criticality subsystem inherits the requirements of the higher criticality system that it is communicating with, generating high certification costs. Such a problem increases in complex vehicles vetronic systems with advanced technologies such as United Nation peace protection armoured vehicles and some vehicles used by public services. This is not acceptable when certification is required for only a subset of subsystems. In this paper we define systems having heterogeneous communicating subsystems with multi-criticality and multi-security issues as systronic systems. This article contributes to an initial framework for the design of a systronic system with the concept of a connector that respects safety and security constraints. The goal of this connector is to control communications between different subsystems, while preserving the safety and the security of each subsystem without additional costs.