Publikationsserver der Ostbayerischen Technischen Hochschule Regensburg
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Integration and Evaluation of Different FPGA based Hardware Accelerators for the AES Algorithm in the TLS Protocol to be Used in Critical Automation Systems
This thesis addresses the challenges of hardware-assisted cryptography in the context of automation systems in critical infrastructures. While hardware accelerators enhance cryptographic calculations in both performance and security, their permanence poses issues in adapting to evolving security concerns. To overcome this problem, we integrated and evaluated a hardware accelerator for the AES algorithm on an FPGA within a TLS application, comparing its performance with other accelerators. Employing a hybrid FPGA-CPU processor system, this setup achieves over 800 Mbit/s data rates, showcasing a more than 27 times acceleration in TLS transmissions compared to purely software-based solutions. The FPGA's flexibility and upgradability therefore make it an ideal platform for critical infrastructure, ensuring longevity and superior acceleration in TLS data transfers
Von der Handarbeit zur Hochtechnologie im Reallabor: Die Möglichkeit der BIM-basierten Planung und effizienten Produktion von Ziegelwänden durch Roboter
Approximating under the Influence of Quantum Noise and Compute Power
The quantum approximate optimisation algorithm (QAOA) is at the core of many scenarios that aim to combine the power of quantum computers and classical high-performance computing appliances for combinatorial optimisation. Several obstacles challenge concrete benefits now and in the foreseeable future: Imperfections quickly degrade algorithmic performance below practical utility; overheads arising from alternating between classical and quantum primitives can counter any advantage; and the choice of parameters or algorithmic variant can substantially influence runtime and result quality. Selecting the optimal combination is a non-trivial issue, as it not only depends on user requirements, but also on details of the hardware and software stack. Appropriate automation can lift the burden of choosing optimal combinations for end-users: They should not be required to understand technicalities like differences between QAOA variants, required number of QAOA layers, or necessary measurement samples. Yet, they should receive best-possible satisfaction of their non-functional requirements, be it performance or other. We determine factors that affect solution quality and temporal behaviour of four QAOA variants using comprehensive density-matrix-based simulations targeting three widely studied optimisation problems. Our simulations consider ideal quantum computation, and a continuum of scenarios troubled by realistic imperfections. Our quantitative results, accompanied by a comprehensive reproduction package, show strong differences between QAOA variants that can be pinpointed to narrow and specific effects. We identify influential co-variables and relevant non-functional quality goals that, we argue, mark the relevant ingredients for designing appropriate software engineering abstraction mechanisms and automated tool-chains for devising quantum solutions from high-level problem specifications
Reproducibility Report for ACM SIGMOD 2023 Paper: Ready to Leap (by Co-Design)? Join Order Optimisation
The paper “Ready to Leap (by Co-Design)? Join Order Optimisation on Quantum Hardware” proposes the first approach to solve the problem of join order optimization on quantum hardware. The authors characterize the applicability and limitations of current state-of-the-art quantum hardware, i. e. gate-based quantum computing and quantum annealing, for join ordering and recommend key improvements to the physical hardware to reach practical utility. Based on the provided database queries and QPU system processing data, we have been able to reproduce the original paper’s key insights and quantum problem characteristics reported in its experimental section. The authors provided a self-contained and fully automated reproduction package, including data (database queries, statistics, and collected QPU processing data), experiment scripts, and plotting routines that
allowed the identical reconstruction of the three main figures in the paper
Automated Vulnerability Scanner for the Cyber Resilience Act
This paper explores the mitigation of the compliance burdens faced by manufacturers of digital products under the Cyber Resilience Act. After providing a concise overview of the Cyber Resilience Act and pinpointing pivotal areas where tool-based interventions could reduce the regulatory strain on manufacturers, we introduce two prototypes: a digital checklist for product classification and a prototype to streamline the analysis and monitoring of the security state of software along the software development life cycle. As the second prototype is based on Static Application Software Testing and Software Component Analysis, we validate the approach through benchmark tests. While Static Application Software Testing tools show promise in identifying vulnerabilities, additional tests are needed for full compliance with the Cyber Resilience Act. In general, the prototypes serve as an entry point for identifying possible automation potential to alleviate the compliance burdens of manufacturers
Konzept zur KI-gestützten parametrischen Brückenmodellierung für ressourcen- und kostenoptimierte Bauwerksentwürfe
Brückenbauwerke stellen eine wesentliche Komponente einer soliden Infrastruktur dar.
Wegen vernachlässigter Instandsetzungsmaßnahmen und sich verändernder Anforderungen sind für eine Vielzahl dieser Bauwerke in Deutschland Ersatzneubauten notwendig. Diese Arbeit adressiert die Herausforderungen der Ressourcenverschwendung durch wiederholten Arbeitsaufwand bei individuellen Brückenentwürfen für die angesprochenen Bauwerke. Es wird ein parametrisches Entwurfsmodells in Siemens NX entwickelt, um den Entwurfsprozess zu beschleunigen und eine einfache Anpassung an die entsprechenden Rahmenbedingungen zu ermöglichen. Zudem wird eine effektive Methode zur Anbindung an die Kostenermittlungssoftware RIB iTWO vorgestellt, die eine nachgelagerte Kostenkalkulation nach DIN 276 ermöglicht. Aufbauend darauf wird ein Optimierungsworkflow vorgestellt, welcher verschiedene Faktoren einbindet, um einen hochwertigen Bauwerksentwurf zu erzielen. Hierbei wird die Einbindung von Techniken aus dem Bereich der Künstlichen Intelligenz angestrebt. Die vorgestellte Methodik soll die Wirtschaftlichkeitsbewertung und Entscheidungsfindung für die Realisierung der Brückenentwürfe erleichtern und somit zu einer effizienteren Nutzung von
Ressourcen im Brückenbau beitragen
On selecting hypothesis tests for group differences
Deciding on the right method of analyzing empirical research data can be difficult – especially when it comes to choosing specific methods of inferential statistics, where there is often not one right way, but a variety of valid options (e.g., using an ANOVA or its non-parametric alternative for data that is not perfectly normally distributed). Novice researchers not only lack the experience to know when a particular hypothesis test is appropriate, but struggle to find suitable literature to familiarize themselves (i.e., literature that is not too superficial, yet comprehensible). With the present article we provide a remedy following the didactic method of scaffolding: We present a systematization of the most elementary inferential statistical methods, namely hypothesis tests for group differences. We start by explaining basic terms (e.g., independent variable) and then give step-by-step instructions for choosing a proper hypothesis test based on data properties, implementing it from scratch, and reporting or interpreting its results. With these practical cookbook-like guidelines, this article serves as a concise starting point for young researchers entering the field of empirical research, as a valuable resource for their instructors, and as a basis for automating statistical procedures in a software system
Quantitative surveys of refugees
Contribution to the Ad Hoc Group “Möglichkeiten der quantitativen Erforschung schwer erreichbarer, versteckter und marginalisierter Bevölkerungsgruppen
Assessment of a MACsec-based Security System for Use in Critical Infrastructure Communication
This paper investigates the integration of Media Access Control Security (MACsec) into the communication of critical infrastructure, specifically within power grid applications, such as Substation Automation Systems (SAS) using the IEC 61850 standard. Building on the principles of both standards, this study aims to determine if MACsec can meet the security and performance requirements set by IEC 62351 for power system communications.
Furthermore, a test environment containing a number of Intelligent Electronic Devices (IEDs) supporting communication compliant to all IEC 61850 message types is established to evaluate this integration. The results of the measurements executed in this environment indicate that MACsec could secure all types of messages, such as Manufacturing Message Specification (MMS), Sampled-Value (SV) and Generic Object Oriented Substation Events (GOOSE), within the required time periods without significant delays. Even with additional encryption activated in the cipher suite, the resulting transmission times are well below the required times. This suggests that MACsec can enhance the security goals for industrial communication by providing confidentiality in addition to the already mandated assurance of authenticity and integrity to all messages without compromising performance. Only the requirement for end-to-end security cannot be met by MACsec in this configuration, as the security system re-encrypts with every hop of the transmission. For this reason, we propose a hybrid approach of Transport Layer Security (TLS) and MACsec as part of future work