Finding Botnets Using Minimal Graph Clusterings

On the computational complexity of finding a minimal basis for the guess and determine attack

Guess-and-determine attack is one of the general attacks on stream ciphers. It is a common cryptanalysis tool for evaluating security of stream ciphers. The effectiveness of this attack is based on the number of unknown bits which will be guessed by the attacker to break the cryptosystem. In this work, we present a relation between the minimum numbers of the guessed bits and uniquely restricted...

On Finding Graph Clusterings with Maximum Modularity

Modularity is a recently introduced quality measure for graph clusterings. It has immediately received considerable attention in several disciplines, and in particular in the complex systems literature, although its properties are not well understood. We study the problem of finding clusterings with maximum modularity, thus providing theoretical foundations for past and present work based on th...

Finding Graph Clusterings with varying coarseness

Density-Constrained Graph Clustering

Clusterings of graphs are often constructed and evaluated with the aid of a quality measure. Numerous such measures exist, some of which adapt an established measure for graph cuts to clusterings. In this work we pursue the problem of finding clusterings which simultaneously feature guaranteed intraand good intercluster quality. To this end we systematically assemble a range of cut-based bicrit...

Generating Significant Graph Clusterings

Many applications such as experimental evaluations of clustering algorithms require the existence of a significant reference clustering. This task is dual to finding significant clusterings of a given graph. We present several generators for pre–clustered graphs based on perturbation and geometry. In an experimental evaluation we confirm the applicability of our generators. Furthermore, the pre...