Pallas: Novel Sound Classification at the Edge

Sound pollution is becoming an increasingly pressing issue in today’s world. To effectively address it, it must be measured. To this end, Serval was developed, an edge-ai powered sound recognition solution. Its lack of accuracy, however, makes it difficult to deploy. This thesis examines the potential for improving this solution while staying...

Unmasking the Power of Trigger Intensity in Federated Learning: Exploring Trigger Intensities in Backdoor Attacks

Federated learning allows a multitude of contributors to collaboratively build a deep learning model, all while keeping their individual training data private from one another. However, it is not immune to security flaws such as backdoor attacks in which malevolent adversaries manipulate the global model to trigger specific behaviors. In this...

Privacy Analysis of Decentralized Federated Learning

Privacy concerns in federated learning have attracted considerable attention recently. In centralized networks, it has been observed that even without directly exchanging raw training data, the exchange of other so-called intermediate parameters such as weights/gradients can still potentially reveal private information. However, there has been...

Under-Screen Camera Detection

Hidden spy cameras are a growing worldwide threat to people’s intimacy and privacy. With the growing interest in full-screen devices and the underlying development of under-screen cameras, a new type of potential security risk is introduced. Recent smartphones such as the ZTE AXON 40 already demonstrate that it’s infeasible to detect the camera...

A computer-checked library of category theory: Formally verifying currying via the product-exponential adjunction

Existing implementations of category theory for proof assistants aim to be as generic as possible in order to be reusable and extensible, often at the expense of readability and clarity. We present a (partial) formalisation of category theory in the proof assistant Lean limited in purpose to explaining currying, intended to be faithful to the...

A computer-checked library of category theory: Defining functors and their algebras

Category theory is a branch of abstract mathematics that aims to give a high-level overview of relations between objects. Proof assistants are tools that aid in verifying the correctness of mathematical proofs. To reason about category theory using such assistants, fundamental notions have to be defined. Computer-checked libraries contain all...

The monad and examples from Haskell: A computer-checked library for Category Theory in Lean

Category Theory is a widely used field of Mathematics.<br/>Some concepts from it are often used in functional programming.<br/>This paper will focus on the Monad and a few implementations of it from Haskell.<br/>We will also present the computer-checked library we have written to help us in this task.

A Computer-Checked Library of Category Theory: Universal Properties of Category Theory in Functional Programming

Category theory is a branch of mathematics that is used to abstract and generalize other mathematical concepts. Its core idea is to take the emphasis off the details of the elements of these concepts and put it on the relationships between them instead. The elements can then be characterized in terms of their relationships using various...

Introducing Privacy-Enhancing Technologies to Consortium Blockchains

Blockchain technology has revolutionized the way data is stored, managed, and shared across various industries. Its decentralized nature and immutability make it highly attractive in use cases that require transparency, integrity, and accountability. However, some applications demand confidentiality, necessitating the development of permissioned...

Scaling Up, Staying Secure: Assessing the Cyber Risks of Distributed Energy Resources in the Smart Grid

Distributed Energy Resources (DER), like solar panels, are projected to take over power generation responsibilities. This will happen during the transition of the current power grid to the Smart Grid. Due to the importance of this power to society, it is crucial that the grid stays stable.<br/><br/>DER devices are similar to IoT devices in scale...

Attacks on Searchable Symmetric Encryption Systems: Revisiting Similar-data and File Injection Attacks

The amount of data individuals create keeps increasing every year to the point that the data cannot be stored on a single device anymore. Cloud storage provides a solution for this problem, but not everybody wants the cloud storage service providers to peek at their data and they thus encrypt their data before storing it on the service provider...

RPL-based Passive OS Fingerprinting in Low-power and Lossy Wireless Sensor Networks

Since the introduction of networking protocols for Low-power and Lossy Networks (LLN), many implementations have been created in the form of (real-time) Operating Systems (OS), simplifying their usage and making the technology more widely available. The low cost and low complexity of LLNs allow for large-scaled wireless sensor deployments,...

Methodological Considerations in Exploit Prediction Systems

The growing number of software vulnerabilities being disclosed is posing a challenge to many organisations. With limited patching resources and only a fraction of the vulnerabilities posing a real threat, prioritization is key. Current prioritization methods, such as CVSS, are failing and are sometimes no better than random guessing. Exploit...

Approximate Gradient Inversion Attack on Federated Learning

Federated learning is a private-by-design distributed learning paradigm where clients train local models on their own data before a central server aggregates their local updates to compute a global model. Depending on the aggregation method used, the local updates are either the gradients or the weights of local learning models. Unfortunately,...

Early-Warning-Driven Approach for Network Protection Against Earthquakes

Natural disasters can significantly disturb communication networks. There are examples of events causing massive connectivity failures in the past, such as the Great East Japan Earthquake. Network protection mechanisms have been developed to cope with the destructive power of natural disasters and mitigate their impact on connections...

Bubblechain: An IoT authentication system

Authentication of domains has been a crucial part of the growth of web browsing, especially for e-commerce and secure browsing. However, the digital space has expanded from web domains to include devices such as smart cars, smart houses, and other IoT devices. The future for these devices is to communicate autonomously with one another, also...

Multi-Functional Privacy-Preserving Data Aggregation: With Malicious User Detection

In practice, many applications like traffic monitoring and smart grids rely on computing functions on privacy-sensitive data. In order to protect privacy-sensitive data and still keep the ability to compute any arbitrary function, multi-functional privacy-preserving data aggregation schemes have been created. These schemes, however, can be...