Transport Layer DOS Attack Generator and Protection

Tato bakalářská práce se zaměřuje na problematiku síťových útoků Denial of Service a obranu proti těmto útokům. V práci je vysvětleno fungování počítačových sítí, principy útoků DoS a obrana. Druhá část práce se zabývá návrhem a implementací aplikace, která dokáže generovat síťové útoky SYN flood, UDP flood a ICMP flood. V závěru práce je popsán průběh testování aplikace a zhodnocení dosažených výsledků.This bachelor thesis focuses on the issues of Denial of Service attacks and the defense against them. It explains the inner workings of computer networks, the principles of DoS attacks and the defense against them. The second part of the thesis focuses on the design and deployment of an application that is able to generate network attacks SYN flood, UDP flood and ICMP flood. The conclusion of this thesis describes the process of testing the application and evaluation of the achieved results.

Modelování a simulace komplexních systémů

1 Úvod S: Podívej, pořídil jsem si novou knihu. M: nechápu, proč si v dnešní době ještě kupuješ knihy. Všechno najdeš na internetu. S: To je ta dnešní mládež, všechno by hledala na internetu. Jenže abys něco našel na internetu, nejdřív potřebuješ vědět, co vlastně máš hledat. navíc intelektuální stravování na internetu se podobá stravování ve fast-foodu: rychle, levně, nekvalitně a většinou si k tomu dáš nezdravý zákusek, který jsi původně vůbec nechtěl. M: Přestaň mě poučovat a raději mi řekni, o čem je ta tvoje nová kniha? S: Jmenuje se "Modelování a simulace komplexních systémů'. Modely určitě znáš: třeba mapa jako model terénu nebo autíčko na hraní jako model reálného auta. Tady v té knize se mluví o výpočetních modelech. Představ si třeba počítačový model pohybu koulí na kulečníkovém stolu - model tvoří rovnice popisující pohyb koulí, simulací tohoto modelu dostáváš obrázek na monitoru, který vizualizuje pohyb koulí

Virtual Tour in VR

Tato diplomová práce se zabývá tvorbou virtuálních prohlídek ve virtuální realitě. Věnuje se panoramatickým fotografiím a jejich využití při tvorbě virtuálních prohlídek. V rámci této práce byly navrhnuty a implementovány dvě aplikace. První z nich jako webový editor pro vytváření a druhá jako mobilní aplikace pro prohlížení virtuálních prohlídek. Vytvořené řešení poskytuje komplexní nástroj pro práci s virtuálními prohlídkami.This thesis deals with the making of virtual tours in the virtual reality. It deals with panoramic photographs and their use in creating virtual tours. In this thesis, two applications were designed and implemented. The first one as a web editor for creating and the other as a mobile application for viewing virtual tours. The created solution provides a comprehensive tool for working with virtual tours.

An Analysis of Response Times in Adaptive Practice of Geography Facts

ABSTRACT Online educational systems can easily measure both answers and response times. Student modeling, however, typically focuses only on correctness of answers. In this work we analyze response times from a widely used system for adaptive practice of geography facts. Our results show that response times have simple relationship with the probability of answering correctly the next question about the same item. We also analyze the overall speed of students and its relation to several aspects of students' behaviour within the system

An Efficient Normalisation Procedure for Linear Temporal Logic and Very Weak Alternating Automata

In the mid 80s, Lichtenstein, Pnueli, and Zuck proved a classical theorem stating that every formula of Past LTL (the extension of LTL with past operators) is equivalent to a formula of the form $\bigwedge_{i=1}^n \mathbf{G}\mathbf{F} \varphi_i \vee \mathbf{F}\mathbf{G} \psi_i$, where $\varphi_i$ and $\psi_i$ contain only past operators. Some years later, Chang, Manna, and Pnueli built on this result to derive a similar normal form for LTL. Both normalisation procedures have a non-elementary worst-case blow-up, and follow an involved path from formulas to counter-free automata to star-free regular expressions and back to formulas. We improve on both points. We present a direct and purely syntactic normalisation procedure for LTL yielding a normal form, comparable to the one by Chang, Manna, and Pnueli, that has only a single exponential blow-up. As an application, we derive a simple algorithm to translate LTL into deterministic Rabin automata. The algorithm normalises the formula, translates it into a special very weak alternating automaton, and applies a simple determinisation procedure, valid only for these special automata.Comment: This is the extended version of the referenced conference paper and contains an appendix with additional materia

Parallel Recursive State Compression for Free

This paper focuses on reducing memory usage in enumerative model checking, while maintaining the multi-core scalability obtained in earlier work. We present a tree-based multi-core compression method, which works by leveraging sharing among sub-vectors of state vectors. An algorithmic analysis of both worst-case and optimal compression ratios shows the potential to compress even large states to a small constant on average (8 bytes). Our experiments demonstrate that this holds up in practice: the median compression ratio of 279 measured experiments is within 17% of the optimum for tree compression, and five times better than the median compression ratio of SPIN's COLLAPSE compression. Our algorithms are implemented in the LTSmin tool, and our experiments show that for model checking, multi-core tree compression pays its own way: it comes virtually without overhead compared to the fastest hash table-based methods.Comment: 19 page

Adaptive Forgetting Curves for Spaced Repetition Language Learning

The forgetting curve has been extensively explored by psychologists, educationalists and cognitive scientists alike. In the context of Intelligent Tutoring Systems, modelling the forgetting curve for each user and knowledge component (e.g. vocabulary word) should enable us to develop optimal revision strategies that counteract memory decay and ensure long-term retention. In this study we explore a variety of forgetting curve models incorporating psychological and linguistic features, and we use these models to predict the probability of word recall by learners of English as a second language. We evaluate the impact of the models and their features using data from an online vocabulary teaching platform and find that word complexity is a highly informative feature which may be successfully learned by a neural network model.Cambridge Assessmen

ASAP: An Extensible Platform for State Space Analysis

Abstract. The ASCoVeCo State space Analysis Platform (ASAP) is a tool for performing explicit state space analysis of coloured Petri nets (CPNs) and other formalisms. ASAP supports a wide range of state space reduction techniques and is intended to be easy to extend and to use, making it a suitable tool for students, researchers, and industrial users that would like to analyze protocols and/or experiment with different algorithms. This paper presents ASAP from these two perspectives.