Master Thesis Defense<\/strong><\/h4>\n\n\n\nTitle:<\/strong> Conceptualization and Validation of Credential Management Systems for IIoT Components<\/p>\n\n\n\nAbstract<\/strong>: The Industrial Internet of Things requires credential management throughout the device lifecycle. This thesis maps an existing, protocol-independent and formally verified credential management model onto MQTT and Murrelektronik\u2019s cybersecurity requirements. The mapping focuses on identity, authentication, and trust, while privilege enforcement remains application-specific and is addressed using MQTT mechanisms.<\/p>\n\n\n\nThe implementation on a constrained IIoT device covers the credential lifecycle from initial provisioning through replacement to decommissioning. It demonstrates that the generic model can be applied to MQTT on constrained hardware and satisfies the considered industrial requirements. The thesis identifies differences between the model and these requirements and proposes practical additions, including an empty phase, staged credential replacement, certificate tracking, separate manufacturer and customer credentialing, and domain-specific certificate authorities. The result is a laboratory demonstration rather than a production system.<\/p>\n\n\n\n
30.09.2026 14:15-14:30 <\/strong>Robert Meysen Bachelorthesis kickoff presentation<\/strong><\/h4>\n\n\n\nTitle:<\/strong> Differentiating two-mirror-systems that project a function<\/p>\n\n\n\nAbstract<\/strong>: In my bachelor\u2019s project, I investigate the properties of mirrors that project a function in two-dimensional space. The function originates orthogonally from the x-axis in the form of simple rays of light for a set range of x-values. They are then reflected by two separate mirrors and projected back onto the same axis, again hitting the axis in a 90-degree angle. Each ray originating in point x hits the axis in a coordinate that corresponds to its y-value in f(x) starting from a pre-determined origin of y along the axis.
The task in my bachelor\u2019s project is to find a way to reliably calculate the differential equation of the two mirrors used in this setup. I will also research what properties f(x) needs to have, in order for the mirrors to be differentiable.<\/p>\n\n\n\n30.09.2026 14:35-15:05 <\/strong>Kai Doersing Bachelorthesis kickoff presentation<\/strong> <\/h4>\n\n\n\nTitle:<\/strong> 3D Extension of Aronov\u2019s Visibility Algorithm<\/p>\n\n\n\nAbstract<\/strong>: This thesis investigates Aronov\u2019s visibility algorithm in three-dimensional environments. The underlying geometric concepts are analyzed, with particular attention to visibility relations, critical events, and the resulting decomposition of visible regions. The algorithm is implemented and its correctness, computational complexity, and practical performance are evaluated on representative geometric configurations.<\/p>\n\n\n\n28.09.2026 14:00-14:30 Omar Hegab <\/strong> Bachelorthesis final presentation<\/strong> (only online)<\/h4>\n\n\n\nTitle:<\/strong> How Tight Are Conductance-Based Bounds for Rumour Spreading on Star-Like Graphs?<\/p>\n\n\n\nAbstract<\/strong>: This thesis investigates the tightness of conductance-based bounds for synchronous PUSH\u2013PULL rumour spreading on star and spider graphs. It compares general conductance bounds with direct graph-specific analyses and shows how the graph structure and arm length influence the spreading time. Simulations support the theoretical results and highlight when conductance provides an accurate estimate and when it overestimates the actual runtime.<\/p>\n\n\n\n23.09.2026 14:00-14:30 Arthur Diener <\/strong> Bachelorthesis final presentation<\/strong><\/p>\n\n\n\nTitle:<\/strong> Implementation and Evaluation of a Self-stabilizing Network<\/p>\n\n\n\nAbstract<\/strong>: Structured overlay networks such as Skip Graphs provide efficient O(log n) routing capabilities for decentralized peer-to-peer systems but lack resilience against transient faults. The Skip+ protocol addresses this vulnerability by combining the hypercubic topology of Skip Graphs with the self-stabilization paradigm theoretically guaranteeing recovery from any arbitrary state within O(log\u00b2 n) rounds. A practical implementation and empirical examination of these theoretical bounds have previously been missing.
In this colloquium, I present the first software implementation of the Skip+ algorithm and its underlying Linearization with Shortcut Neighbors protocol. Using a custom discrete-time simulation framework, I evaluate the average-case runtime complexity, the protocol resilience, and the hypercubic routing efficiency. The empirical results demonstrate that Skip+ stabilizes faster than its theoretical worst-case bound, showing convergence behavior closer to O(log n). The protocol also demonstrates resilience by autonomously recovering from a simultaneous failure of forty percent of its nodes. Large-scale Monte-Carlo routing simulations with up to 100,000 nodes demonstrate the stable O(log n) routing efficiency.
<\/p>\n\n\n\n23.09.2026 14:35-15:10 Luca Diringer <\/strong> Bachelorthesis final presentation<\/strong><\/p>\n\n\n\nTitle:<\/strong> Algebraic Reduction and Characterization of Equal Distance Point Pairs in Triangular Reflection Geometries<\/p>\n\n\n\nAbstract<\/strong>: In reflective environments such as two dimensional acoustic rooms or optical sensing spaces, finding equal distances between complex reflection paths usually requires heavy floating point matrix calculations. This thesis introduces an algebraic framework that converts physical reflection sequences into symbolic words built from a free Coxeter group alphabet. We prove that equal internal distances between two reflection path pairs (w1, w2) and (v1, v2) are strictly guaranteed if either w2 w1^R v1 v2^R = epsilon or w2 w1^R v2 v1^R = epsilon holds under Dyck language reductions, where $w^R$ denotes word reversal.
<\/p>\n\n\n\n23.09.2026 15:10-15:30 Mattis Bless <\/strong> Master Thesis intermediate presentatio<\/strong>n<\/h4>\n\n\n\nTitle:<\/strong> Design and Analysis of Communication Protocols for Mental Card Game Shuffle based on the Elgamal Crypto-System<\/p>\n\n\n\nAbstract<\/strong>: In this presentation, we again discuss how the zero-knowledge proof of the shuffle’s expensive re-masking step can be improved. Our first presentation on this improvement in August showed that our idea of using a technique similar to the one presented by Bayer and Groth in their 2012 paper “Efficient Zero-Knowledge Argument for Correctness of a Shuffle” still suffered from a major problem: It proved to be difficult to show that the ciphertexts that re-mask the original, already permuted ciphertexts are elements from the subgroup that is used by the encryption scheme. In this presentation, we show how the problem can be solved by restricting the encryption scheme to specific subgroups. We still achieve a reduction of both communication and computation in the re-masking step despite this constraint.<\/p>\n\n\n\n23.09.2026 15:35-16:00 Nikita Kroh <\/strong> Bachelorthesis final presentation<\/strong><\/h4>\n\n\n\nTitle:<\/strong> Design, Implementation, and Evaluation of a Cryptographic Hash Function based on a 3D Ray-Tracing Cryptographic System<\/p>\n\n\n\nAbstract<\/strong>: While a 3D ray-tracing cryptographic system has only been used as an encryption system, we want to adapt it into a cryptographic hash algorithm. We embed the encryption process into the transformation function of the sponge construction. This thesis introduces the modification of the padding algorithm to allow UTF-8 string messages as an input and the selection of the parameters used for the cryptographic hash algorithm. We also describe the transformation function containing the conversion from bit string to light ray, the encryption process, and the conversion from light ray to bit string in detail. Finally, we empirically evaluate the collision resistance and the avalanche effect, with both results matching the theoretical expectations.<\/p>\n\n\n\n15.09.2026 14:00-14:30 Alexander Keller<\/strong> Bachelorthesis final presentation<\/strong><\/h4>\n\n\n\nTitle: <\/strong>A Distributed Protocol for Offline-Verifiable Event Races<\/p>\n\n\n\nAbstract<\/strong>: This thesis presents a distributed protocol that determines which of N mutually distrusting players acted first in a peer-to-peer race, and lets any one player prove the outcome afterwards. The proof is a single transcript of signed messages, and can be verified deterministically by any honest party.<\/p>\n\n\n\nWe present a solution consisting of two parts: a transcript generation protocol that runs during the game, and a deterministic verification algorithm that runs afterwards on a single transcript. We also provide a detailed analysis of each part.<\/p>\n\n\n\n
15.09.2026 14:45-15:15 Franka M\u00fcller<\/strong> Bachelorthesis final presentation<\/strong><\/h4>\n\n\n\nTitle: <\/strong>Integration von surrogat-assistierter Optimierung in den Optimierungsansatz des Energiesystemmodels REMod<\/p>\n\n\n\nAbstract<\/strong>: The thesis investigates the optimization approach used in REMod, an energy system model developed at the Fraunhofer Institute. Two approaches were tested to extend and improve the model by incorporating surrogate models.
In the first step, the study examined to what extent the simulation function itself could be replaced by a surrogate model. A neural network, an XGBoost model, and a trust-region model were evaluated. Overall, these models achieved good relative error values, indicating that the simulation function can, in principle, be approximated by a surrogate model. However, it remains unclear to what extent these models are suitable for optimization, as the absolute cost values differ substantially from those obtained through the actual evaluations. Their accuracy is therefore insufficient to support the precise search for the global minimum using the CMA-ES algorithm employed in REMod.
A second approach was subsequently investigated, examining three different extensions of the CMA-ES algorithm: replacing the function within the current CMA-ES search region; using a surrogate model that learns and improves the behavior of CMA-ES; and employing a hybrid model that combines both approaches. Here, too, the surrogate models reached the limits of their approximation capabilities, primarily because the ratio of training samples to problem dimensions was too low.
Overall, the results show that REMod\u2019s high dimensionality represents a major challenge for surrogate modeling. However, the positive experience with surrogate-assisted optimization in other energy system models suggests that further developing and applying this approach to REMod may still offer significant potential.<\/p>\n\n\n\n10.09.2026 14:00-14:30 Luca Diringer Bachelorproject final presentation<\/strong> (only online)<\/h4>\n\n\n\nTitle: <\/strong>Localization of a point in a two dimensional triangular space through direct and reflected signals<\/p>\n\n\n\nAbstract: We consider the Indoor Localization through Direct And Reflected Signals (ILDARS) within a two-dimensional, triangular space. The setup
consists of a single transmitter and a single receiver enclosed by three reflecting walls. The primary objective is to analyze the geometric and acoustic properties of this specific configuration to determine a robust solution. To achieve this, we developed a custom Python simulator to model ray-propagation dynamics and analyze the patterns formed by image sources across different reflection orders. By exploiting these patterns and the distance-preserving properties of reflections (isometries), we formulate a closed-form quadratic equation as a solution. Ultimately, this approach calculates both the shape of the room and the position of the transmitter, providing there is sufficient signal coverage.<\/p>\n\n\n\n
7.09.2026 11:00-12:00 Kevin Niedermaier Bachelor Thesis final presentation<\/strong><\/h4>\n\n\n\nThe market for Low Power Wide Area Network (LPWAN) has seen strong growth in recent years, driven by the increasing demand for low-power, long-range connectivity inInternet of Things (IoT) applications. Within this market, LoRaWAN is widely establishedin the industry, while mioty still lags behind in adoption. This means that many potential customers are locked into the LoRaWAN ecosystem due to their existing infrastructure, even though the mioty protocol might be more suitable for their use case.This thesis attempts to mitigate this by developing an approach for evaluating a new communication protocol within an existing network infrastructure, without requiring a full migration. Using mioty and LoRaWAN as a concrete case, multiple approaches areevaluated that can aid in this kind of evaluation. Each approach shall support basicLoRaWAN features and shall log all available information aiding in the evaluation.Following this evaluation, LoRa Gateway Emulation was selected as the architecture tobe implemented within the project. The resulting Virtual Gateway allows the connectionof a mioty base station to a LoRaWAN Network Server (LNS) by adjusting the formatof messages. After an initial configuration by the user, it can autonomously handle the joining of new devices and can survive a reboot by persistently saving its device registry.All messages, including their transmission statistics, are logged to a file to allow analysis of the mioty protocol.The Virtual Gateway is meant as a temporary means for evaluation, not a permanent one. It was designed with a specific configuration of LNS and mioty base station in mind, and is meant to be run in a local, secure network, since encryption is removed from themessage once it reaches it.<\/p>\n\n\n\n
02.09.2026 14:00-14:30 Maximilian Herych Bachelor Thesis kickoff presentation<\/strong><\/h4>\n\n\n\nTitle: Commitment only shuffle for mental card games \u2013 Implementation of the permutation network encoding into arithmetic circuits<\/strong><\/p>\n\n\n\nAbstract: This thesis is the starting point of an implementation for the commitment only shuffle by M. Bless, which tries to minimize communication by reducing the shuffle to commitments that can then easily be transmitted. The shuffle is based on a permutation network which is converted into arithmetic circuits, the players can then use zero-knowledge proofs on the equations describing these circuits.
The scope of this thesis is limited to the construction of a permutation network that is pruned or expanded to the desired size while limiting bias and the translation into arithmetic circuits. Which is used in the permuting and rerandomization of the deck. The implementation will be in rust to allow integration into existing works in the mental card game repository.<\/p>\n\n\n\n
02.09.2026 14:40-15:10 Lorik Hamza Bachelor Thesis final presentation<\/strong><\/p>\n\n\n\nTitle: Analyse kryptographischer Protokolle f\u00fcr die didaktische Aufbereitung in der gymnasialen Oberstufe<\/strong><\/p>\n\n\n\nAbstract: This thesis explores how the topic of “Mental Card Games” can be used to introduce advanced cryptographic concepts in an educational and accessible way. Mental Card Games are cryptographic protocols that allow players to play card games fairly over a network without relying on a trusted third party. The thesis focuses not only on the underlying cryptographic principles, such as secure shuffling, encryption, and verification, but especially on how these concepts can be simplified and presented to students in an intuitive manner.
As part of the project, teaching materials for two lessons were developed, implemented, and evaluated in an upper-secondary-school setting. A major goal is to examine which concepts are suitable for classroom use, which difficulties occur, and how the teaching approach can be improved. In this way, the thesis aims to make modern cryptography more understandable, interactive, and engaging for beginners and high school students.
The presentation is the final presentation of my bachelor thesis.<\/p>\n\n\n\n
02.09.2026 15:10-15:40 Zeinab Herz<\/h4>\n\n\n\n
Intermediate presentation of her Bachelor Thesis:<\/strong> Objekterkennung und Distanzbestimmung in Verkehrsszenen auf Basis von Time-of-Flight-Kameras<\/p>\n\n\n\n<\/p>\n\n\n\n
02.09.2026 15:50-16:15 Regina Qelibari Bachelor thesis kickoff presentation
<\/strong>
Title : Zero-Knowledge Proofs for RSA Arithmetic in the Exponent of a Composite-Order Subgroup
<\/strong>
Abstract:
In this kick-off talk, I outline my bachelor’s thesis plan, which studies RSA-like arithmetic in a cyclic subgroup of composite order. The project considers the construction of subgroups of order n = pq inside Z*_p\u0302, where p, q, and p\u0302 = 2kpq + 1 are prime, and empirically investigates how frequently suitable parameters occur. Building on this construction, the thesis aims to study whether classical zero-knowledge techniques for proving exponent and multiplication relations can be adapted to verify the correct evaluation of expressions such as Y = g\u0303^(m^e mod n) mod p\u0302. The talk sketches the planned experimental and theoretical methodology and the main evaluation questions concerning composite-order group structure, proof soundness, additional security conditions, and possible cryptographic applications or limitations.<\/p>\n\n\n\n19.08.2026 14:00-14:30 Regina Qelibari project final presentation<\/h4>\n\n\n\n
Title: Attack on Third-degree Polynomial Objects in 3D Visual Cryptography System<\/strong><\/p>\n\n\n\nAbstract:<\/strong> This bachelor project investigates the reconstruction of third-degree implicit polynomial surfaces in a 3D visual cryptography system based on ray tracing. Several polynomial fitting methods are implemented and compared using both monomial and Chebyshev polynomial bases. Their reconstruction accuracy, numerical stability, and robustness are evaluated on representative cubic objects that resemble the polynomial surfaces used in the optical component of the cryptographic scheme. To simulate imperfect surface samples that may occur during a practical reconstruction attack, Gaussian noise and outliers are added to the training data used for polynomial fitting. The performance of the reconstruction methods is evaluated under both ideal and noisy conditions. This work contributes to the analysis of third-degree polynomial surface reconstruction as a building block for future cryptanalysis of the proposed 3D visual cryptography scheme.2.08.2026 14:00-14:30 Alexander Horst Keller Bachelor project final presentation<\/p>\n\n\n\n12.08.2026 14:00-14:30 Alexander Horst Keller Bachelorproject final presenation<\/strong><\/p>\n\n\n\nTitle: An Interpreter for a Card-Game Domain-Specific Language<\/strong><\/p>\n\n\n\nAbstract:<\/strong> Card games have well-defined rules but complex implementations: turn orders, scoring, and conditional logic typically live in hand-coded state machines that are difficult to rule changes, hard to verify, and coupled to their runtime. This project addresses that separation by building a deterministic interpreter for CGDSL, a domain-specific language that describes a game once and derives execution, testing, replay, and visualization from that description. I implemented the interpreter as the cgdsl-engine crate: a Rust FSM engine in which stages become loops, actions mutate a flat game state, and queries read it. A quantifier preprocessor rewrites all\/any\/range edges into concrete edges or player prompts at runtime, so the IR itself is never mutated. Every DSL-reachable failure is a typed, recoverable EngineError – no engine panic is reachable from well-formed input. Hosts interact through an InputSource seam, per-transition trace events with typed payloads, and opt-in file or tracing-based logging. The engine is verified by 518 tests across five layers: unit, interpreter, fixtures, deterministic behavioral games, and randomized 40-seed playthroughs over 73 .cgdsl fixtures, including five complete demo games (Blackjack, War, Crazy Eights, Five-Card Draw, Go Fish). The language and parser predate this project; the engine is currently consumed only by its own binaries and tests, with cryptography, networking, and UI integration as the next projects.<\/p>\n\n\n\n12.08.2026 15:00-15:30 Ben de Boer Bachelor Thesis kickoff presentation<\/h4>\n\n\n\n
Title: Conception, Prototypical Implementation, and Evaluation of Reactive Power Control For Inverters<\/strong><\/p>\n\n\n\nAbstract:<\/strong>
As the distribution grid is adapted for decentralized, bidirectional power flow, voltage-regulation challenges rise, that reactive power (Q) can address at the point of connection. While German regulation converges on EEBus as the minimum standard, its defined use cases cover only active power, reactive power dispatch is absent. This thesis proposes a new EEBus use Case for continuous Q(t) setpoint dispatch from the Distribution Grid Operator to inverters, with local Q(V) droop as failsafe per standard for emergency power limitation of consumer devices.<\/p>\n\n\n\n07.08.2026 13:00-13:30 Mattis Bless Master Thesis intermediate presentation<\/h4>\n\n\n\n
Title : Design and Analysis of Communication Protocols for Mental Card Game Shuffle based on the El Gamal Crypto-System<\/strong><\/p>\n\n\n\nAbstract :<\/strong> In this presentation, we discuss how the zero-knowledge proof of the shuffle’s remasking step can be improved. The remasking step involves creating a ciphertext of the empty message for each card. These ciphertexts are then multiplied to the permuted cards’ existing ciphertexts. The resulting ciphertexts appear random to the other players, and the underlying permutation is hidden from them. The original approach makes use of a large arithmetic circuit to generate the remasking ciphertexts. The circuit’s size results in large vectors, e. g. to represent the edges, as well as many equations to describe the circuit. The number of equations and the vectors’ sizes are reflected in the amount of communication and computation during the zero-knowledge proof. Inspired by a technique used in the shuffle argument by Bayer and Groth in their 2012 paper “Efficient Zero-Knowledge Argument for Correctness of a Shuffle”, we aim at reducing both communication and computation by proving that a single equation holds. The equation shows that the remasking ciphertexts hidden behind a commitment are created using exponents, also hidden behind a commitment, with overwhelming probability. This is achieved by evaluating a polynomial in the exponent of both sides of the equation at a random challenge coming from the honest verifier. In contrast to the former arithmetic citcuit approach, this allows smaller vectors and requires fewer equations to be proven.<\/p>\n\n\n\n07.08.2026 13:45-14:15 Lorik Hamza Bachelor Project final presentation<\/strong><\/h4>\n\n\n\nTitle : Mental Card Games Based on Paillier Encryption<\/strong><\/p>\n\n\n\nAbstract:<\/strong> Mental card games allow several players to play card games over a public network without the need for a trusted dealer. The main challenge is to keep the cards secret while ensuring that all game actions are per- formed correctly and can be verified by every player. This report presents and analyzes a construction of mental card games based on the Paillier cryptosystem. The homomorphic properties of Paillier encryption are used to mask and re-mask cards, while distributed
key generation and zero-knowledge proofs are intended to provide security and public verifiability. In addition, the correctness of the decryption algorithm is explicitly demonstrated when using Euler\u2019s totient function \u03c6(N ) instead of the Carmichael function \u03bb(N ).
Finally, the distributed key construction is analyzed and a critical information leak is identified. The published values g^(\u03c6i) , together with the public decryption factor \u03bc^(\u22121), allow \u03c6(N ) to be recovered. Consequently, the construction does not achieve the intended confidentiality or the n-out-of-n threshold decryption property. The analyzed construction is based on the protocol presented in Mental Poker Revisited.<\/p>\n\n\n\n23.07.2026 11:00-11:30 Nils Steuernagel Bachelor Project final presentation<\/h4>\n\n\n\n
Title : Scaling of 3D Objects relative to Local Bounding Boxes<\/strong>
Abstract<\/strong> : This bachelor\u2019s project addresses the scaling of three dimensional polynomial surfaces within Local Bounding Boxes (LBBs) in a ray tracing based cryptographic framework. The proposed method uses scale free parameters and scaling rules based on the half extent H of each bounding box to preserve the relative geometry of the surfaces across different box sizes. In addition, the parameter ranges were revised, and the plotting functionality and offset generation were improved.<\/p>\n\n\n\n23.07.2026 11:35-12:05 Tom Pfirsig Bachelor Thesis final presentation<\/h4>\n\n\n\n
Title: Der \u00dcbergang zu Post-Quanten-Ringsignaturen in Blockchain-Systemen- Eine Fallstudie am Beispiel von Privacy-Coins (Monero)<\/strong>
Abstract:<\/strong> Privacy-Coins versprechen Vertrauen auf einer ansonsten transparenten Blockchain. Am Beispiel von Monero (XMR) untersucht diese Arbeit, wie tragf\u00e4hig dieses Versprechen unter der Annahme eines kryptographisch relevanten Quantencomputers bleibt. Die drei tragenden Datenschutzschichten von Monero, verkn\u00fcpfbare Ringsignaturen (MLSAG\/CLSAG), Ring Confidential Transactions (RingCT) mit Pedersen- Commitments sowie Stealth-Adressen auf Basis des Elliptic-Curve-Di!e-Hellman-Austauschs ruhen s\u00e4mtlich auf der H\u00e4rte des Elliptic Curve Discrete Logarithm Problem (ECDLP). Genau dieses Problem l\u00f6st Shors Algorithmus in polynomieller Zeit.
Die Arbeit ist als systematische Fallstudie angelegt. Sie f\u00fchrt die ben\u00f6tigten Grundlagen ein (Ringsignaturen, elliptische Kurven, Quantencomputing, Gitterkryptographie), analysiert die Monero-Architektur und leitet schichtweise her, welche Datenschutzeigenschaft unter Shor verloren geht. Besondere Aufmerksamkeit gilt dem Harvest-Now-Decrypt-Later -Szenario (HNDL), das Privacy-Coins r\u00fcckwirkend und unwiderruflich trifft. Anschlie\u00dfend werden publizierte Post-Quanten-Bausteine (RAPTOR, MatRiCT\/MatRiCT+, ML-KEM) auf ihre Eignung gepr\u00fcft, zu einem Integrations- und Migrationskonzept f\u00fcr das Gesamtprotokoll zusammengef\u00fchrt und abschlie\u00dfend zwei Migrationspfade verglichen: ein vollst\u00e4ndig gitterbasierter Pfad
und die vom Monero-Projekt real eingeschlagene FCMP++-Entwicklung.
Die Analyse zeigt, dass keiner der beiden Pfade f\u00fcr sich allein alle drei Datenschutzdimensionen quantensicher l\u00f6st: FCMP++ h\u00e4rtet die Absenderanonymit\u00e4t einschlie\u00dflich retroaktiver Forward Secrecy mit kompakten Beweisen, l\u00e4sst aber Betr\u00e4ge und Empf\u00e4ngerableitung ECC-gebunden; der Gitterpfad deckt alle Schichten ab, scheitert jedoch an deutlich gr\u00f6\u00dferen Transaktionen, einer Vertauschung der Hiding- und Binding-Eigenschaften der Commitments und der ungel\u00f6sten Integration quantenresistenter Stealth-Adressen. Ein vollst\u00e4ndig quantensicheres Monero
erfordert daher die Kombination beider Ans\u00e4tze, deren Schnittstellen offene Forschungsfragen bleiben. Aufgrund des HNDL-Drucks auf den bereits heute archivierbaren On-Chain-Datensatz bleibt eine zeitnahe Migration dringlich.
<\/p>\n\n\n\n23.07.2026 12:10-12:40 Alexander Horst Keller Bachelor Thesis kickoff presentation <\/h4>\n\n\n\n
Title:<\/strong> A Distributed Protocol for Offline-Verifiable Reaction Tests <\/strong>
Abstract:<\/strong> I will be presenting my planned bachelor’s thesis, in which I design and analyze a distributed protocol for reaction tests.<\/p>\n\n\n\n22.07.2026 12:00-12:30 Omar Hegab Bachelor Project final presentation
Title : Approximate Data Aggregation on Star Graphs Using Gossip-Based Protocols<\/h4>\n\n\n\n
Abstract :<\/strong> Distributed systems frequently need to compute global quantities, such as sums or averages, without collecting all data at a central location. This occurs, for example, in sensor networks in which many devices measure local values and communicate through a common
gateway. Gossip-based algorithms are well suited to such settings because they rely only on repeated local exchanges and do not require global coordination. This project studies the Push-Sum protocol, a gossip-based algorithm for distributed averaging, on a star graph. The star topology represents a highly asymmetric communication structure: all communication between the leaves must pass through a single center
node. This asymmetry makes the standard intuition from homogeneous or fully connected networks difficult to apply directly.
We develop a star-specific convergence analysis based on contribution vectors and a potential function measuring the deviation from the correct average. By exploiting the symmetry among the leaves, the evolution of the expected potential is reduced to a two-dimensional recurrence describing the center and leaf contributions separately. We then analyze the mean squared error of the actual ratio estimates and obtain an upper bound of O(n log (1\/\u03b5)) rounds for reducing the expected MSE below a threshold \u03b5, assuming a fixed initial scale. The analysis also explains why the individual sum and weight variables need not converge, although their ratio still approaches the correct average. Finally, numerical
simulations support the theoretical results and illustrate the characteristic difference between potential and estimate convergence.<\/p>\n\n\n\n22.07.2026 12:35 – 13:00 Colin Duchilio Bachelor Project final presentation<\/h4>\n\n\n\nTitle : Node Pairing & Creating a Lobby System for Mental Card Games<\/h4>\n\n\n\n
Abstract:<\/strong> In his Project, Benjamin Schliebitz created a rust-based codebase for Mental Card Games. Absent from this codebase was a way to play games together with others. This project built upon said codebase in order to remedy that, by utilizing the Iroh crate to implement a peer-to-peer connection and communication system, as well as implementing a lobby system for players to come together and play a game, utilizing QR Codes as easy connection entry points.<\/p>\n\n\n\n16.07.2026 12:00-12:30 Jonathan Schmiederer Bachelor Thesis final presentation<\/h4>\n\n\n\nTitle: Human Factors of Key Verification in Encrypted Messengers: A System for Field Studies
<\/h4>\n\n\n\n
Abstract :<\/strong> End-to-end encryption is important for securing private communication in mobile messengers, but an active attacker may break it with a Man-in-the-Middle attack. To defend against this, messengers offer features that let users verify their chat
partners\u2019 public keys. Numerous laboratory studies have examined the usability of these features, yet how users perform key verification outside the laboratory has remained unexamined.
For this thesis I developed a privacy-preserving telemetry system that enables what is, to the best of my knowledge, the first field study on key verification, and implemented it in Delta Chat, a messenger whose unusual approach to key verification makes it especially interesting to study. The system is designed to let users see what data is collected, reflecting the constraints of a secure messenger. It was accepted into the official Delta Chat for Android app.
In a pilot study, I demonstrated that the system makes such a field study feasible and produces meaningful data, while also clarifying which research questions can and cannot be answered by instrumenting the messaging application.<\/p>\n\n\n\n15.07.2026 14:00-14:30 Prof. Dr. Sevil Sen Research Seminar presentation<\/h4>\n\n\n\n
Title: Current Challenges in AI-Driven Cybersecurity<\/strong>
Abstract:<\/strong> This interactive research seminar will focus on current research challenges at the intersection of artificial intelligence, cybersecurity, and computer networks. After a short introduction by Professor Sevil Sen on ongoing research at Hacettepe University, participants are invited to present their own research interests and discuss possible collaborations. Topics include explainable AI, malware analysis, IoT security, federated learning, large language models for security applications, and emerging directions in trustworthy AI for cybersecurity.<\/p>\n\n\n\n15.07.2026 16:00-16:30 Shuran Liu Bachelor Thesis final presentation
Title: Investigating RSA Exponentiation and Its Relationship to Subgroups of Order n<\/h4>\n\n\n\n
Abstract:<\/strong> This presentation studies RSA exponentiation from a group-theoretic perspective. In traditional RSA, the product of two primes is mainly used as the modulus for computation. In this work, it is instead treated as the order of a cyclic subgroup. The main goal is to construct such a subgroup and examine how RSA-like exponentiation behaves inside it.
The construction is based on choosing suitable parameters and generating a cyclic subgroup whose order is equal to the RSA modulus. Experimental tests with different parameter sizes show that suitable parameters can be found for the tested examples. Based on this subgroup, an RSA-like encryption and decryption process is introduced, and its correctness is discussed.
However, because the subgroup has composite order, standard security arguments for prime-order groups cannot be applied directly. Additional conditions are needed, especially when extracting secret values from different protocol transcripts.
Overall, this work provides a framework for connecting RSA-like exponentiation, cyclic subgroups, and zero-knowledge proofs. Future work includes a more detailed implementation of multiplication proofs, the integration of committed primality proofs, and a deeper security analysis of zero-knowledge protocols over composite-order subgroups. Another possible direction is to study whether the hidden-order version of the construction can be developed into a more secure cryptographic scheme.
<\/p>\n\n\n\n08.07.2026 14:00\u201314:45 Luca Diringer <\/strong>Bachelor Thesis kickoff presentation
Title: Characterizing Equal-Distance Point Pairs in Exponential Reflection Trees<\/h4>\n\n\n\nAbstract<\/strong> : In a triangular room containing a sender and a receiver, we aim to determine the sender’s position and reconstruct the geometry of the room using only the Time Difference of Arrival (TDoA) and the Angle of Arrival (AoA), without any additional information. To achieve this, we identify pairs of image points whose mutual distance is equal to that of another pair of image points. These equal-distance relationships provide additional constraints that allow the localization and reconstruction problem to be solved using only a small number of image points.
The primary objective of this thesis is to identify as many such equal-distance conditions as possible and to derive a general characterization of their occurrence within the exponential reflection tree. This characterization enables these patterns to be recognized for arbitrary reflection orders.<\/p>\n\n\n\n01.07.2026 14:00\u201314:45 Lars Schmitt <\/strong>Master Project final presentation
Title : Introducing randomization in the 2D Ray tracing based Cryptographic scheme<\/h4>\n\n\n\nAbstract<\/strong> : This project analyzes the IND-CPA security of a two-dimensional ray-tracing-based cryptographic scheme. Since the original construction is deterministic, identical plaintexts always produce identical ciphertexts, making the scheme insecure against chosen-plaintext attacks. To address this, two non-deterministic variants are proposed: one uses pseudorandom masks derived from a synchronized counter and shared key, while the other applies a fresh random mask during encryption. Both approaches prevent deterministic ciphertexts and achieve IND-CPA security under standard cryptographic assumptions. The encryption and decryption procedures, security properties, and practical trade-offs\u2014including synchronization, randomness, communication overhead, and implementation complexity\u2014are analyzed and compared.<\/p>\n\n\n\n01.07.2026 14:40-15:04 Jonathan Altherr <\/strong>Bachelor Thesis kickoff presentation
Title: Achieving IND-CPA Security in a Ray-Tracing-Based Encryption Scheme<\/strong><\/h4>\n\n\n\nAbstract<\/strong>: This presentation outlines the approach to achieving IND-CPA security in a ray-tracing-based encryption scheme. The existing scheme is currently vulnerable to chosen-plaintext attacks because it is deterministic: two identical plaintexts will always result in the same ciphertext for a given key.<\/p>\n\n\n\nThis Bachelor\u2019s thesis focuses on the practical realization of a counter-based approach to secure the scheme against chosen-plaintext attacks, with special regard to the following topics:<\/p>\n\n\n\n
\n- Developing a robust method to apply a mask to starting rays without breaking geometric validity.<\/li>\n\n\n\n
- Implementing the counter-based method into the existing Python-based 2D project.<\/li>\n\n\n\n
- Investigating whether masks generated by the existing ray-tracing scheme provide sufficient path divergence or if an additional CSPRNG is needed.<\/li>\n\n\n\n
- Evaluating the implementation\u2019s performance, security, and robustness.<\/li>\n\n\n\n
- Ensuring the system remains simple to use and computationally efficient.<\/li>\n<\/ul>\n\n\n\n
01.07.2026 15:15\u201315:45 Zeinab Herz \u2014 Bachelor Thesis Kickoff Presentation
Title: Object Detection and Distance Estimation in Traffic Scenes Using Time-of-Flight Cameras<\/h4>\n\n\n\n
Title:<\/strong>
Close overtaking of cyclists by motor vehicles remains a significant road safety issue. <\/p>\n\n\n\nAbstract:<\/strong>
Das zu enge \u00dcberholen von Fahrradfahrern durch Kraftfahrzeuge stellt ein relevantes Problem f\u00fcr die Verkehrssicherheit dar. Um solche Situationen besser untersuchen zu k\u00f6nnen, besch\u00e4ftigt sich diese Bachelorarbeit mit der automatisierten Analyse von \u00dcberholvorg\u00e4ngen im Stra\u00dfenverkehr. Ziel ist es, Verkehrsteilnehmer zu erkennen, ihre Positionen zu bestimmen und daraus Informationen \u00fcber \u00dcberholsituationen abzuleiten.
Als Sensortechnologie wird eine Time-of-Flight-Kamera (ToF-Kamera) eingesetzt. Diese erm\u00f6glicht die Erfassung der Umgebung durch verschiedene Datenrepr\u00e4sentationen: Intensit\u00e4tsbilder, Tiefenkarten sowie dreidimensionale Punktwolken. Diese Informationen bieten die Grundlage f\u00fcr die weitere Auswertung der Verkehrsszene.
Ein Schwerpunkt der Arbeit liegt auf der Objekterkennung. Dabei sollen insbesondere Fahrradfahrer, Kraftfahrzeuge und Passanten zuverl\u00e4ssig erkannt werden. Die Identifikation der beteiligten Verkehrsteilnehmer ist eine wesentliche Voraussetzung, um \u00dcberholvorg\u00e4nge zu erfassen und festzustellen, welches Objekt ein anderes \u00fcberholt.
Aufbauend auf der Objekterkennung werden erkannte Verkehrsteilnehmer \u00fcber die Zeit verfolgt und ihre r\u00e4umlichen Beziehungen analysiert. Abschlie\u00dfend soll die Distanz zwischen Kraftfahrzeugen und Fahrradfahrern w\u00e4hrend eines \u00dcberholvorgangs bestimmt werden. Die gewonnenen Ergebnisse k\u00f6nnen einen Beitrag zur automatisierten Analyse von Verkehrssituationen leisten.<\/p>\n\n\n\n24.06.2026 14:00\u201314:30 Mattis Bless \u2014 Master Thesis Kickoff Presentation<\/strong>
Title:<\/strong> Efficient Shuffle for Mental Card Games \u2013 Revisited<\/h4>\n\n\n\nAbstract:<\/strong>
In this thesis, we revisit the problem of a communicationally efficient multiplayer zero-knowledge shuffle argument for mental card games without a trusted third party. The original argument is based on permutation networks, which are then transformed into arithmetic circuits. The circuits are described by efficient zero-knowledge arguments, resulting in the desired zero-knowledge argument for the correctness of the shuffle. Other shuffle arguments typically require each player to know the shuffled ciphertexts in order to check the argument’s correctness, causing a large communication overhead. In comparison, the shuffle argument in this thesis only requires the players to know small commitments to the ciphertexts.<\/p>\n\n\n\nHowever, this commitment-only shuffle argument still suffers from several limitations that we aim to address. The first goal is to reduce the original argument’s bias towards certain permutations caused by the chosen permutation network. Besides further reducing the communication requirements, for example in the remasking step of the shuffle, we also investigate what we call a provably secure shuffle<\/em>. In such a shuffle, the applied permutation depends not only on the shuffling player’s choice but also on publicly available input whose value cannot be anticipated or significantly influenced. This ensures that even if all players collude, they cannot intentionally position cards during the shuffle. Such manipulation could not be prevented in the original approach, which assumes that at least one player is honest.<\/p>\n\n\n\n24.06.2026 14:45\u201315:15 Selin Keles \u2014 Master Thesis Kickoff Presentation
Title:<\/strong> Making Flip Networks Secure<\/h4>\n\n\n\nAbstract:<\/strong>
Flip networks are dynamic, connected, regular peer-to-peer overlays whose topologies are continuously transformed through distributed random 1-Flipper operations. Although these transformations can improve the expansion and robustness of the network, an adversary may attempt to manipulate the selection, coordination, or execution of flip operations and thereby influence the resulting topology.<\/p>\n\n\n\nThis thesis investigates the security of flip networks in the presence of colluding malicious peers, churn, and concurrent topology transformations. It defines fundamental security objectives, including soundness, randomness, generality, and convergence, and identifies flip-network-specific attacks that threaten these properties. Based on this analysis, the thesis aims to design protection mechanisms against selected attack models and formally prove their security guarantees, ensuring that the flip network remains secure against the considered attacks.<\/p>\n\n\n\n
24.06.2026<\/strong> 15:25\u201315:55 Nikita Kroh \u2014 Bachelor Thesis Kickoff Presentation<\/strong>
Title:<\/strong> Creating a Hashing Algorithm Based on the 3D Ray-Tracing Cryptographic System<\/p>\n\n\n\nAbstract:<\/strong>
The current 3D ray-tracing-based cryptographic system is well suited for encrypting and decrypting plaintext. In this thesis, our goal is to create a hashing algorithm based on this 3D ray-tracing cryptographic system. To achieve this, we investigate how to derive a valid light ray from a password of arbitrary length, which information should be collected during the ray-tracing process, and how the collected information can be compressed into a fixed-length output. Finally, we evaluate whether the resulting algorithm satisfies the irreversibility requirements of a cryptographic hash function.<\/p>\n\n\n\n24.06.2026 16:00\u201316:30 Alexander Horst Keller \u2014 Research Presentation
Title:<\/strong> The Button Game: A P2P DAG-Based Delayed-Reveal Protocol<\/p>\n\n\n\nAbstract:<\/strong>
In a peer-to-peer reaction game, fair and secure ordering of events while maintaining low latency is a challenging problem. This presentation introduces a DAG-based protocol designed to mitigate frontrunning and censorship by Byzantine participants in a partially synchronous network.<\/p>\n\n\n\nThe protocol combines a delayed-reveal mechanism with threshold cryptography to prevent frontrunning and employs a deterministic linearization algorithm to derive a total order of events from a transcript of the game. The resulting design aims to provide fairness and security while preserving responsiveness in distributed reaction games<\/p>\n\n\n\n
\n- 16.06.2026 14:00-14:30 Omar Hegab Bachelor Thesis Kickoff Presentation<\/strong>
Title: How Tight Are Conductance-Based Bounds for Rumor Spreading on Star-Like Graphs?<\/strong>
Abstract: How tight are the general conductance-based bounds for PUSH-PULL rumor spreading from the paper \u201cAlmost Tight Bounds for Rumour Spreading with Conductance\u201d by Chierichetti, Lattanzi, and Panconesi on star-like graphs?
We start with the star graph and then analyze subdivided stars, also called spider graphs. The idea is to calculate the conductance, derive graph-specific lower and upper bounds for the worst-case source position, and compare them with the general theorem from the paper. This exemplifies the general theorem capturing the runtime on these graph families or whether the hub structure leads to a significant gap. Simulations will illustrate the theoretical results.<\/li>\n\n\n\n- 10.06.2026 14:00-14:30 Muhammed Can Yeni<\/strong> Bachelor Project final presentation<\/strong>
Title: Extending the Gate-Based Ray-Tracing Cryptography with Isotropic and Anisotropic Scattering Mechanisms
<\/strong>Abstract: The gate-based ray-tracing cryptography by Mohanty, Peairs, and Schindelhauer encrypts data through the deterministic tracing of light rays through a two-dimensional scene with polynomial reflection and refraction surfaces. In this project work, the scheme is extended by two scattering mechanisms that introduce a pseudo-random but deterministically invertible deviation from the ideal reflection direction after each reflection, thereby strengthening the diffusion properties of the cipher.
The isotropic scattering is based on an XOR construction with a 64-bit key mask and uses the self-inverse property of XOR (a \u2295 b \u2295 b = a) for recovery. The anisotropic scattering models a Gaussian distribution around the reflection direction via inverse transform sampling and is algebraically invertible through the corresponding cumulative distribution function. Both methods are integrated into the existing system without modifying the non-optical gates (XOR, MatrixMix, NOT-Shift).
Encryption and decryption are functionally implemented in Python. Numerical precision issues along the ray trajectory lead to small deviations in the reconstructed direction; a revised code base addresses these by using the mpmath library (arbitrary precision arithmetic) together with additional buffer bits in the individual encryption steps. The migration of the presented scattering mechanisms onto this revised code base remains as future work.<\/li>\n\n\n\n- 19.05.2026 10:00-10:30 Zeinab Herz Bachelor Project kickoff presentation<\/strong>
Title: Optical particle analysis using an event-driven camera and laser sheet triangulation
<\/strong>Abstract: Dynamic Image Analysis (DIA) refers to the real-time evaluation of image sequences to extract size, shape, and positional information of moving particles. Accurate optical analysis of particles in free fall is challenging because particles do not pass through a perfectly defined plane: their distance to the camera varies. These depth variations lead to significant errors in size estimation, as perspective projection strongly depends on distance. This project investi- gates an approach that combines event-based camera technology with laser-sheet triangulation. Event-based cameras offer extremely high temporal resolution and respond only to changes in the scene, reducing redundant data. A thin laser sheet projected across the falling path allows particle passages to be detected with high temporal precision. The implemented pipeline estimates particle distance from the vertical image position and estimates diameter using distance-condition-specific lookup tables. The initial goal was to reduce the relative size error by a factor of 3. In the experimental evaluation, the mean distance-dependent relative size error was reduced by a factor of 2.15. The target was therefore not fully reached, but the correction substantially reduced systematic size drift across the evaluated recording distances<\/li>\n<\/ul>\n\n\n\n\n- 18.05.2026 12:00-12:30 Hans Albert Bachelor Thesis kickoff presentation
Title: Complexity of Gravity Assist Maneuvers in 2D
<\/strong>Abstract: After we showed in the Bachelor Project that 1D Gravity Assist is NP-complete, this thesis investigates the complexity of 2D Gravity Assist maneuvers. The work focuses on defining suitable models for two-dimensional gravity assist systems and constructing reductions from the 1D problem to the 2D setting in order to establish NP-hardness results.<\/li>\n\n\n\n- 18.05.2026 12:35-13:05 Noah Berg Bachelor Project kickoff presentation
Title: Funhouse Mirror Calculation \u2013 Simulation of a Mirror Representing a Mathematical Function
<\/strong>Abstract: This project presents an initial approach for calculating mirrors that represent a given mathematical function within a two-dimensional Cartesian coordinate system. The mirror shape is approximated by determining the required slope at each individual point along the function. In addition, a graphical application is developed to visualize the resulting mirror and its optical properties.<\/li>\n\n\n\n- 18.05.2026 13:10-13:40 Arthur Diener Bachelor Thesis kickoff presentation
Title: Implementation and Evaluation of the Self-Stabilizing Skip+ Network
<\/strong>Abstract: Peer-to-peer systems are highly dynamic networks in which nodes may join and leave at any time. Without appropriate recovery mechanisms, failures or attacks can drive the overlay network into illegal states, degrading routing efficiency and network stability. Skip graphs provide scalable overlay structures with logarithmic diameter and degree, but their standard implementation suffers from structural challenges in unstable environments.
This thesis investigates the Skip+ network, an extension of skip graphs that is locally checkable and self-stabilizing. Theoretical results show convergence in