Keywords: critical infrastructures, modelling, system interdependencies, electrical networks, telecommunication networks, cross-domain cascading, cascading failures, failure propagation
High-level modelling of critical infrastructures' interdependencies
Due to the increasing demand in services' quality and the growing concerns about external threats, the protection of critical infrastructures has recently become a major concern. In this article, we study the potential effect of interdependencies that may occur between two of these infrastructures: the telecommunication networks and the electrical network. In the absence of side protection mechanisms such as multihoming or batteries, these types of networks highly depend on each other. A failure of some component in one of these architectures may cause a fault in the other, for example, when an electrical outage occurs, routers may be switched off as soon as their battery has depleted. This can lead to cross-domain cascading effects in failures propagation that cause general service unavailabilty. To understand this phenomena, we propose a model that describes the behaviour of these interdependent systems. We show on realistic topologies that simple failures can lead to failures propagation and we derive the potential risk scenarios.