Controlled DDoS Attack on IPv4/IPv6 Network Using Distributed Computing Infrastructure

The paper focuses on design, background and experimental results of real environment of DDoS attacks. The experimental testbed is based on employment of a tool for IT automation to perform DDoS attacks under monitoring. DDoS attacks are still serious threat in both IPv4 and IPv6 networks and creation of simple tool to test the network for DDoS attack and to allow evaluation of vulnerabilities and DDoS countermeasures of the networks is necessary. In proposed testbed, Ansible orchestration tool is employed to perform and coordinate DDoS attacks. Ansible is a powerful tool and simplifies the implementation of the test environment. Moreover, no special hardware is required for the attacks execution, the testbed uses existing infrastructure in an organization. The case study of implementation of this environment shows straightforwardness to create a testbed comparable with a botnet with ten thousand bots. Furthermore, the experimental results demonstrate the potential of the proposed environment and present the impact of the attacks on particular target servers in IPv4 and IPv6 networks

Vibration of the cantilever beam using a piezoelectric actuator.

This paper deals with experimental and finite element analysis of vibration of the aluminum beam excited by a piezoelectric thin film actuator. One beam's end was fix supported and vibration of the beam's free end was measured using laser displacement sensor. Finite element model of the beam with piezoelectric actuator was created and three types of analyses were performed: modal, transient and harmonic. Results from finite element analyses were compared with data from experimental measurements

NOVÉ POZNATKY O DEVÍNSKONOVOVESKOM SÚVRSTVÍ (VIEDENSKÁ PANVA, SLOVENSKO)

Coarse-grained sediments of the Devínska Nová Ves Formation (Middle Badenian) are cropping out at the western margin of the Malé Karpaty Mts., between Devínska Nová Ves and Kuchyňa villages. In the studied area, this formation is represented by various lithofacies. The most abundant are breccia, gravel and sand. Less abundant is the presence of shale and coaly shale with lignite seams. In one place, south of the Kuchyňa village, also a presence of volcanic tuff was examined in this formation. The breccia is built by chaotic, nonstratified, mostly angular blocks and debris of granitoid rocks. Less frequent is poorly rounded debris of crystalline schists, vein quartz and quartzite in the breccia. Its matrix is silty sand and represents a material of fossil weathering rind. Locally, the Devínska Nová Ves Fm. is represented by gravel with well rounded pebbles of granitoids, quartzite and crystalline schists in the Marianka village and south of the Lozorno village. All these rock types can be derived from the Tatric units of the Malé Karpaty Mts., but their vertical distribution (MKZ-1 well) show an inverse trend, than awaited from normal stratigraphic superposition. This is an evidence of the existence of a crystalline nappe unit (Bratislava nappe), above the Mesozoic successions (Borinka unit). Most of the sediments were deposited in the lateral debris apron and alluvial fan environments. In the terminal part of the coarse grained formation, a part of the rounded gravel shows reworking by sea waves in the littoral zone, beyond the frontal part of the alluvial fans.Sand represents a very common lithotype in the Devínska Nová Ves Formation, containing also thin intercalations of fine gravel, and 1–2 cm thick interbeds of shale. The sand is genetically related mostly to the distal alluvial sand skirt deposits, but the distal part of them, cross stratified, with reworked pebble trains, clearly show the deposition in littoral environment of alluvial deltas. Shale lithofacies is present only rarely in the Devínska Nová Ves Formation. It is represented by pale greenish grey, rusty variegated noncalcareous clay. It contains an abundant association of palynomorphs, documenting hydrophilous and riparian paleoflora.The shales were accumulated on alluvial interfluve plains, and more distally they transit into similar delta plain facies. The tuff, found south of the Kuchyňa village, is of white and grey white color. It is matrix supported, and consists of clasts and fragments of glass. It is a product of an ash-fall of rhyolite composition. On the tuff`s bedding planes we have found imprints of leaves and lithocarps. This tuff can be probably derived from the Central Slovakian neovolcanic area, from where rhyolite volcanism isknown from the Early Badenian time only, that forces us to consider also to the Lower Badenian age of the basal part of the Devínska Nová Ves Fm., similarly like it is in the Austrian part of the Vienna Basin

Zu slowakischen Übersetzungen der deutschsprachigen Literatur seit 1990

Die gesellschaftliche Wende 1989 hatte u. a. einen grundsätzlichen Umbau der bisherigen Verlagslandschaft in der Slowakei zur Folge. Wenn die Lage davor und danach verglichen wird, erscheinen markante Unterschiede, die neben anderen herausgegebenen Büchern auch die Übersetzungen aus der deutschsprachigen Literatur betreffen

Nachruf Milan Žitný (1948–2019)

Am 16. April 2019 starb unser hervorragender Kollege und Freund, Literaturwissenschaftler, Hochschulpädagoge und Literaturübersetzer, Dr. habil. Milan Žitný, PhD. Der Absolvent des Studiums der Germanistik und Nordistik an der Philosophischen Fakultät der Comenius-Universität Bratislava begann seine wissenschaftliche Laufbahn als Mitarbeiter des Instituts für Weltsprachen und Literatur an der Slowakischen Akademie der Wissenschaften. Hier promovierte er mit einer Dissertation über junge nonkonformistische DDR-Lyrik

Controlled DDoS Attack on IPv4/IPv6 Network Using Distributed Computing Infrastructure

The paper focuses on design, background and experimental results of real environment of DDoS attacks. The experimental testbed is based on employment of a tool for IT automation to perform DDoS attacks under monitoring. DDoS attacks are still serious threat in both IPv4 and IPv6 networks and creation of simple tool to test the network for DDoS attack and to allow evaluation of vulnerabilities and DDoS countermeasures of the networks is necessary. In proposed testbed, Ansible orchestration tool is employed to perform and coordinate DDoS attacks. Ansible is a powerful tool and simplifies the implementation of the test environment. Moreover, no special hardware is required for the attacks execution, the testbed uses existing infrastructure in an organization. The case study of implementation of this environment shows straightforwardness to create a testbed comparable with a botnet with ten thousand bots. Furthermore, the experimental results demonstrate the potential of the proposed environment and present the impact of the attacks on particular target servers in IPv4 and IPv6 networks

Neural Gas Clustering Adapted for Given Size of Clusters

Clustering algorithms belong to major topics in big data analysis. Their main goal is to separate an unlabelled dataset into several subsets, with each subset ideally characterized by some unique characteristic of its data structure. Common clustering approaches cannot impose constraints on sizes of clusters. However, in many applications, sizes of clusters are bounded or known in advance. One of the more recent robust clustering algorithms is called neural gas which is popular, for example, for data compression and vector quantization used in speech recognition and signal processing. In this paper, we have introduced an adapted neural gas algorithm able to accommodate requirements for the size of clusters. The convergence of algorithm towards an optimum is tested on simple illustrative examples. The proposed algorithm provides better statistical results than its direct counterpart, balanced k-means algorithm, and, moreover, unlike the balanced k-means, the quality of results of our proposed algorithm can be straightforwardly controlled by user defined parameters