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SoK: On the Physical Security of UOV-based Signature Schemes
No full textMultivariate cryptography currently centres mostly around UOV-based signature schemes: All multivariate round 2 candidates in the selection process for additional digital signatures by NIST are either UOV itself or close variations of it: MAYO, QR-UOV, SNOVA, and UOV. Also schemes which have been in the focus of the multivariate research community, but are broken by now - like Rainbow and LUOV - are based on UOV. Both UOV and the schemes based on it have been frequently analyzed regarding their physical security in the course of the NIST process. However, a comprehensive analysis regarding the physical security of UOV-based signature schemes is missing.
In this work, we want to bridge this gap and create a comprehensive overview of physical attacks on UOV and its variants from the second round of NIST’s selection process for additional post-quantum signature schemes, which just started. First, we collect all existing side-channel and fault attacks on UOV-based schemes and transfer them to the current UOV specification. Since UOV was subject to significant changes over the past few years, e.g., adaptions to the expanded secret key, some attacks need to be reassessed. Next, we introduce new physical attacks in order to obtain an overview as complete as possible. We then show how all these attacks would translate to MAYO, QR-UOV, and SNOVA. To improve the resistance of UOV-based signature schemes towards physical attacks, we discuss and introduce dedicated countermeasures. As related result, we observe that certain implementation decisions, like key compression techniques and randomization choices, also have a large impact on the physical security, in particular on the effectiveness of the considered fault attacks. Finally, we provide implementations of UOV and MAYO for the ARM Cortex-M4 architecture that feature first-order masking and protection against selected fault attacks. We benchmark the resulting overhead on a NUCLEO-L4R5ZI board and validate our approach by performing a TVLA on original and protected subroutines, yielding significantly smaller t-values for the latter
Strengthen - for a fair, sustainable, democratic future
No full textUnder the title “Strengths”, the H-BRS annual report traces the diverse activities of the university in the past year 2023. Whether studies, research or transfer: the report not only provides diverse insights into the university's wide range of topics, but also introduces the creative people behind them. For example, Dr. Daryoush Daniel Vaziri, who has been researching AI systems and using them in teaching for eight years. How artificial intelligence has changed and continues to change everyday university life is an important topic in this report. The megatrend of digitalization is examined in various contexts - from the digitalization of administration to the new digital student magazine “Werksgelände” and research into a digital shopping assistant for visually impaired people. The double interview this time revolves around the transformation process: H-BRS President Hartmut Ihne spoke about this with Xiaomeng Shen, Head of the United Nations University Bonn
Der Diskurs über Bildungschancen in deutschen Online-Pressemedien seit der Corona-Krise
No full textDie vorliegende Arbeit untersucht, wie sich der Diskurs über Bildungschancen und -ungleichheiten von Kindern während der COVID-19-Pandemie in Online-Angeboten überregionaler Pressemedien darstellt.
Dazu wurde die Kritische Diskursanalyse nach Jäger (2012) auf zwischen März 2020 und April 2021 veröffentlichte Online-Artikel aus dem Spiegel und FOCUS-Online angewandt.
Die Analyse zeigt, dass Schulschließungen als Hauptfaktor für die Verschlechterung der Bildungschancen und die Zunahme der Chancenungleichheit identifiziert wurden. Homeschooling wurde überwiegend negativ bewertet, noch bevor sich in wissenschaftlichen Daten eine klare Wirkrichtung abzeichnete. Langfristige Lösungsstrategien und die Perspektiven von Schülern und Eltern waren in der Berichterstattung unterrepräsentiert. Im Herbst 2020 wurde in keinem der beiden Online-Angebote über die Grundthematik berichtet. Die Diskursanalyse zeigt auf, wie sich bestimmte „Frames“ in der öffentlichen Besprechung der Bildungschancen während der Corona-Pandemie dominieren und so die Wahrnehmung der Rezipierenden prägen könnten.
Zukünftige Forschung könnte andere Zeitabschnitte, Medienangebote und Diskursebenen einbeziehen, um ein umfassenderes Bild des Diskurses zu zeichnen
Voice Assistants' Accountability through Explanatory Dialogues
No full textAs voice assistants (VAs) become more advanced leveraging Large Language Models (LLMs) and natural language processing, their potential for accountable behavior expands. Yet, the long-term situational effectiveness of VAs’ accounts when errors occur remains unclear. In our 19-month exploratory study with 19 households, we investigated the impact of an Alexa feature that allows users to inquire about the reasons behind its actions. Our findings indicate that Alexa's accounts are often single, decontextualized responses that led to users’ alternative repair strategies over the long term, such as turning off the device, rather than initiating a dialogue about what went wrong. Through role-playing workshops, we demonstrate that VA interactions should facilitate explanatory dialogues as dynamic exchanges that consider a range of speech acts, recognizing users’ emotional states and the context of interaction. We conclude by discussing the implications of our findings for the design of accountable VAs
Social protection policies and fertility: How can social protection measures address the low fertility rate in Germany?
No full textThere are about 30 low-fertility countries globally. Germany has been a low-fertility country for more than 50 years which is longer than any other country since the low-fertility trend in other countries only began ten or twenty years ago. Low-fertility rates have mainly negative consequences for various policy areas such as pension, health care, economy, labour market, culture, elections, and international relations (Bujard, 2015a, pp. 53f.).
Understanding the potential impact of social protection policies on fertility rates is crucial for policymakers who seek to address declining fertility rates by applying evidence-based strategies. By investigating the relationship between these two variables, valuable insights can be gained, informing the design and implementation of effective policies aimed at promoting higher fertility rates and ensuring sustainable demographic outcomes.
This research’s objective is to identify how social protection measures address the low fertility rates in Germany. To do that, the outcomes of recent social protection measures in Germany related to the fertility rate will be assessed by generating empirical evidence. Consequently, conclusions will be drawn, and suggestions will be offered on how to improve fertility rates
