Peter Langendörfer

Elisabeth Vogel, Peter Langendörfer

Resilience in cyber-physical systems of systems (CPSoS) is often assessed using static indices or point-in-time metrics that do not adequately account for the temporal evolution of risk following a disruption. This paper formalizes resilience as a functional of the risk trajectory by modelling risk as a dynamic state variable. It is analytically shown that key resilience properties are structurally determined by maximum deviation (peak) and effective damping, and that cumulative risk exposure depends on their ratio. A simplified energy-dependent system illustrates the resulting differences in peak magnitude, recovery dynamics, and cumulative impact. The proposed approach links resilience assessment to stability properties of dynamic systems and provides a system-theoretically consistent foundation for the analysis of time-dependent resilience in CPSoS.

Kai Lehniger, Marcin J. Aftowicz, Peter Langendörfer et al.

This paper shows how the Xtensa architecture can be attacked with Return-Oriented-Programming (ROP). The presented techniques include possibilities for both supported Application Binary Interfaces (ABIs). Especially for the windowed ABI a powerful mechanism is presented that not only allows to jump to gadgets but also to manipulate registers without relying on specific gadgets. This paper purely focuses on how the properties of the architecture itself can be exploited to chain gadgets and not on specific attacks or a gadget catalog.

R. Natarov, O. Sudakov, Z. Dyka et al.

Resilience aspects of remote electroencephalography sampling are considered. The possibility to use motion sensors data and measurement of industrial power network interference for detection of failed sampling channels is demonstrated. No significant correlation between signals of failed channels and motion sensors data is shown. Level of 50 Hz spectral component from failed channels significantly differs from level of 50 Hz component of normally operating channel. Conclusions about application of these results for increasing resilience of electroencephalography sampling is made.

R. Kovtun, S. Radchenko, A. Netreba et al.

Human eye tracking devices can help to investigate principles of processing visual information by humans. The attention focus movement during the gaze can be used for behavioural analysis of humans. In this work we describe our experimental system that we designed for synchronous recording of electroencephalographic signals, events of external tests and gaze direction. As external tests we used virtual cognitive tests. We investigated the possibility to exploit electroencephalographic signals for eye motion tracking. Our experimental system is a first step for the designing an automatic eye tracking system and can additionally be used as a laboratory equipment for teaching students.

Elisabeth Vogel, Zoya Dyka, Dan Klann et al.

Resilience is a feature that is gaining more and more attention in computer science and computer engineering. However, the definition of resilience for the cyber landscape, especially embedded systems, is not yet clear. This paper discusses definitions of different authors, years and different application areas the field of computer science/computer engineering. We identify the core statements that are more or less common to the majority of the definitions and based on this we give a holistic definition using attributes for (cyber-) resilience. In order to pave a way towards resilience-engineering we discuss a theoretical model of the life cycle of a (cyber-) resilient system that consists of key actions presented in the literature. We adapt this model for embedded (cyber-) resilient systems.

Dmytro Petryk, Zoya Dyka, Jens Katzer et al.

Physically accessible devices such as sensor nodes in Wireless Sensor Networks or "smart" devices in the Internet of Things have to be resistant to a broad spectrum of physical attacks, for example to Side Channel Analysis and to Fault Injection attacks. In this work we concentrate on the vulnerability of ASICs to precise optical Fault Injection attacks. Here we propose to use metal fillers as potential low-cost countermeasure that may be effective against a broad spectrum of physical attacks. In our future work we plan to evaluate different methods of metal fillers placement, to select an effective one and to integrate it as additional design rules into automated design flows.

Dmytro Petryk, Zoya Dyka, Eduardo Perez et al.

Resistive Random Access Memory (RRAM) is a type of Non-Volatile Memory (NVM). In this paper we investigate the sensitivity of the TiN/Ti/Al:HfO2/TiN-based 1T-1R RRAM cells implemented in a 250 nm CMOS IHP technology to the laser irradiation in detail. Experimental results show the feasibility to influence the state of the cells under laser irradiation, i.e. successful optical Fault Injection. We focus on the selection of the parameters of the laser station and their influence on the success of optical Fault Injections.