Understanding the Topological Structure and Semantic Content of Darknet Communities

For over a decade Darknet has been gaining tremendous popularity proportional to the growing concerns fostered by lack of anonymity and privacy on the World Wide Web. In the recent years, illegitimate use of the Darknet has resulted into investigation in the research community that is analogous to a domino effect further adding to popularity of...

Non-intrusive Detection of Compromised PLC's in ICS and SCADA Systems

Classifying scanners: Mapping their behaviour

This thesis focuses on the classification of behavioural aspects of scanners based on unroutable traffic collected from two /16 subnets. Firstly the study determines that the use of a smaller dataset achieves similar results and allows for the same correctness compared to larger ones. Secondly different scanning tools are analysed, and methods...

Last line of defence: Cyber security of industrial control systems

The world is rapidly embracing networked technology and transitioning into one of hyperconnectivity, a term first coined by social scientists Anabel Quan-Haase and Barry Wellman. Increased connectivity provides benefits such as automation and, remote access and control of networks and equipment, thereby decreasing operational costs. Maritime and...

Detecting malicious behaviour using system calls

The emergence of Apple’s Macintosh computers’ popularity introduces new threats and challenges for the security on the Mac. For a long time, OS X security has benefitted from the popularity of Microsoft Windows. The threat landscape for the Mac is rapidly changing as the marketshare of the Mac is approaching 15%1. Malware on Apple’s OS X systems...

DokterService: A Security Information and Event Management System (SIEMS)

KPMG is a multinational firm, which is focused on three pillars: tax advisory, accountancy and advisory. The advisory section, in particular the IT Advisory, required a system that is able to analyze, process and visualize captured network traffic. This network traffic is gathered from the own company or their clients. The goal of this project...

Vulnerability Analysis of Smart Meters

Inferring Private Attributes in Online Social Networks

Online social networks (OSNs) are playing an important role in current world and the way people communicate with each other. Despite the advantage of using online social networks, there are certain privacy risks that can affect users of such services. Since users provide a lot of personal information in OSNs, concerns about how data placed in...

Estimating popularity by sentiment and polarization classification on social media

Mass processing of social media posts has been brought to scientists' attention during the last decade. The massive growth of online social networks, like Twitter and Facebook, have created a need for determining peoples' opinions and moods through these means. This thesis constitutes a research on measuring users' sentiment upon a particular...

Implementing Link-state Update Policies for Quality of Service Routing

This thesis describes the implementation of available bandwidth link-state update policies for Quality of Service routing. Periodic, threshold-based and class-based policies are described and implemented in a QoS router testbed, using Quagga and its OSPF-API for low-level communications. The implementation is thoroughly tested using unit tests...

Efficient Crawling of Community Structures in Online Social Networks

Online social networks showed an enormous growth in the last decade. With the rise of online social networks such as Twitter and Facebook, researchers got the opportunity to access the data of social behavior of millions of people, whereas in the past it was limited to hundreds of people. For these researchers and marketeers it is of great...