Degree theses

Ransomware attacks – in contrast to other cyber attacks – must not be detected and especially not blocked or recovered on first sight. This relaxation is supported by the rareness of ransomware attacks. Certainly, the uprising of ransomware families, which are able to circumvent the detection mechanism, integrated into the local machine, prevents the approaches from taking advantage of the relaxation. Justified by the attack isolation, the move to the personal cloud storage is the reasonable way…

In the past years digital communication became an important aspect in every day life. Everything is shared and discussed in groups of friends, family or business part- ners without a proper way to protect that information. This master thesis introduces the first secure robust multi-party communication protocol which mimics a physical conversation with the help of a Diffie-Hellman key tree and social behaviours. Robust- ness against offline group members is reached by taking advantage of…

In this thesis two generic approaches on how to store different datatypes to a cloud storage are proposed, thereby utilizing Treetank. As part of this thesis implementations for the proposed approaches have been implemented to evaluate their practicability and search out strengths as well as weaknesses. Current cloud storage systems, security concerns towards privacy, stability and integrity of data shared with “the Cloud” is discussed. An overview of Treetank, that originally was designed to be…