@article{FrankBoettgerMexisetal.2023, author = {Frank, Florian and B{\"o}ttger, Simon and Mexis, Nico and Anagnostopoulos, Nikolaos Athanasios and Mohamed, Ali and Hartmann, Martin and Kuhn, Harald and Helke, Christian and Arul, Tolga and Katzenbeisser, Stefan and Hermann, Sascha}, title = {CNT-PUFs: highly robust and heat-tolerant carbon-nanotube-based physical unclonable functions}, volume = {2023}, number = {13(22)}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/nano13222930}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-14011}, pages = {24 Seiten}, year = {2023}, abstract = {In this work, we explored a highly robust and unique Physical Unclonable Function (PUF) based on the stochastic assembly of single-walled Carbon NanoTubes (CNTs) integrated within a wafer-level technology. Our work demonstrated that the proposed CNT-based PUFs are exceptionally robust with an average fractional intra-device Hamming distance well below 0.01 both at room temperature and under varying temperatures in the range from 23 °C to 120 °C. We attributed the excellent heat tolerance to comparatively low activation energies of less than 40 meV extracted from an Arrhenius plot. As the number of unstable bits in the examined implementation is extremely low, our devices allow for a lightweight and simple error correction, just by selecting stable cells, thereby diminishing the need for complex error correction. Through a significant number of tests, we demonstrated the capability of novel nanomaterial devices to serve as highly efficient hardware security primitives.}, language = {en} } @misc{MexisLillDolehetal.2025, author = {Mexis, Nico and Lill, Bjarne and Doleh, Yousef and Katzenbeisser, Stefan}, title = {Supplementary Material for the Work "Exposing the Gaps: The State of Supply Chain Coverage in Current Security Standards"}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-15633}, pages = {29 Seiten}, year = {2025}, abstract = {This document contains the supplementary material for our work "Exposing the Gaps: The State of Supply Chain Coverage in Current Security Standards", which should be consulted for further information and details. While this supplement has not been peer-reviewed, the above article has. The reviewers also had access to all the data presented in this document during the review phase. The article is available from 26 July 2025 as part of the "IFIP Advances in Information and Communication Technology", volume 742: 10.1007/978-3-031-94924-1_14}, subject = {Supply Chain Management}, language = {en} } @misc{Mexis2023, type = {Master Thesis}, author = {Mexis, Nico}, title = {A Comprehensive Comparison of Fuzzy Extractor Schemes Employing Different Error Correction Codes}, volume = {2023}, doi = {10.15475/ccfesedecc.2023}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-12914}, school = {Universit{\"a}t Passau}, pages = {vii, 100 Seiten}, year = {2023}, abstract = {This thesis deals with fuzzy extractors, security primitives often used in conjunction with Physical Unclonable Functions (PUFs). A fuzzy extractor works in two stages: The generation phase and the reproduction phase. In the generation phase, an Error Correction Code (ECC) is used to compute redundant bits for a given PUF response, which are then stored as helper data, and a key is extracted from the response. Then, in the reproduction phase, another (possibly noisy) PUF response can be used in conjunction with this helper data to extract the original key. It is clear that the performance of the fuzzy extractor is strongly dependent on the underlying ECC. Therefore, a comparison of ECCs in the context of fuzzy extractors is essential in order to make them as suitable as possible for a given situation. It is important to note that due to the plethora of various PUFs with different characteristics, it is very unrealistic to propose a single metric by which the suitability of a given ECC can be measured. First, we give a brief introduction to the topic, followed by a detailed description of the background of the ECCs and fuzzy extractors studied. Then, we summarise related work and describe an implementation of the ECCs under consideration. Finally, we carry out the actual comparison of the ECCs and the thesis concludes with a summary of the results and suggestions for future work.}, subject = {Vorw{\"a}rtsfehlerkorrektur}, language = {en} } @techreport{AlmainiAnthuberEggeretal.2026, author = {Almaini, Amar and Anthuber, Stefan and Egger, Gottfried and Grabner, Daniel and Gutbrod, Amelie and Herburger, Michael and Holzer, Laura and Icyer, Abdurrahman and Katzenbeisser, Stefan and Kraxberger, Manuel and Kufner, Sven and Langner, Karoline and Lill, Bjarne and Mexis, Nico and Pichler, Julia and Plasch, Michael and Sauerwein, Clemens and Schramm, Martin and Szilagyi, Daniel and Wagner, Carina and Zeisler, Alexander}, title = {Cyber-Security und Resilienz in Supply Chains mit Fokus auf KMU}, organization = {FH Ober{\"o}sterreich - Logistikum}, doi = {10.15475/cyseres_kmu.2026}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-20549}, pages = {IX, 115 Seiten}, year = {2026}, abstract = {Dieser Best Practice Guide zeigt, wie kleine und mittlere Unternehmen (KMU) ihre Cyber-Resilienz umfassend st{\"a}rken k{\"o}nnen, von der technischen Basis {\"u}ber Lieferketten und Unternehmenskultur bis hin zu Notfallmanagement und OT-Security. Da Cyberangriffe zunehmend komplexer werden und menschliches Verhalten weiterhin in {\"u}ber 80 \% der Vorf{\"a}lle eine entscheidende Rolle spielt, reicht technische Absicherung allein nicht aus. Entscheidend ist ein integrierter Ansatz, der Mindset (sicherheitsbewusste Haltung), Skillset (praktisches Wissen und regelm{\"a}ßige Schulungen) und Toolset (ad{\"a}quate technische L{\"o}sungen) miteinander verbindet. Der Cyber-Security Grundschutz vermittelt KMU praxisnahe Schritte zur Identifikation des IST-Zustands, zur Priorisierung von Schutzmaßnahmen und zur Einf{\"u}hrung eines kontinuierlichen Verbesserungsprozesses nach dem PDCA-Modell. Das Supply Chain Cyber-Security Handbuch verdeutlicht, wie digital vernetzte Lieferketten zu kritischen Angriffspunkten werden k{\"o}nnen und unterst{\"u}tzt Unternehmen dabei, relevante Partner zu identifizieren, zu klassifizieren und risikobasierte Maßnahmen zu implementieren. Das Awareness- \& Kultur-Handbuch zeigt, wie eine „Security-First"-Kultur entsteht, die Cybersicherheit als Teamaufgabe begreift und {\"u}ber Zero-Trust-Prinzipien, klare Verantwortlichkeiten und moderne Lernformate wie Serious Games nachhaltig verankert. Das Cyber-Notfallkonzept bietet KMU einen strukturierten Leitfaden zur Vorbereitung, Reaktion und Wiederherstellung bei Sicherheitsvorf{\"a}llen - inklusive Checklisten, Rollenmodellen und Incident-Response-Pl{\"a}nen, um Ausfallzeiten zu minimieren und handlungsf{\"a}hig zu bleiben. Erg{\"a}nzend vermittelt das OT-Security Handbuch die Besonderheiten industrieller Systeme und zeigt, wie KMU ihre Produktionsumgebungen sch{\"u}tzen k{\"o}nnen - von der Bewertung kritischer Anlagen {\"u}ber sichere Konfigurationen bis zur schrittweisen Umsetzung praxistauglicher OT-Security-Maßnahmen. Gemeinsam bilden die f{\"u}nf Handb{\"u}cher ein ganzheitliches Rahmenwerk, das KMU bef{\"a}higt, Cybersicherheit als festen Bestandteil des Arbeitsalltags zu verankern, Risiken entlang der gesamten Wertsch{\"o}pfungskette zu reduzieren und die eigene Widerstandsf{\"a}higkeit gegen{\"u}ber Cyberbedrohungen systematisch zu erh{\"o}hen.}, language = {de} }