This master’s thesis describes the general information about cryptocurrencies, what principles are used in the process of creation of new coins and why mining cryptocurrencies can be malicious. Further, it discusses what is an IP flow, and how to monitor networks by monitoring network traffic using IP flows. It describes the Nemea framework that is used to build comprehensive system for detecting malicious traffic. It explains how the network data with communications of the cryptocurrencies mining process were obtained and then provides an analysis of this data. Based on this analysis a proposal is created for methods capable of detecting mining cryptocurrencies by using IP flows records. Finally, proposed detection method was evaluated on various networks and the results are further described.

This master's thesis is aimed how can be network traffic monitored using IP flows. The description of NEMEA framework that can be used to build complex intrusion detection system. Following chapters describes port scanning methods and SSH protocol which can be used for remote login to the system, which can be exploited by an attacker. These two areas are intended to be detected in a slow attack manner, when attacker using low attack speed, which he can evade multiple detection methods. Proposed method for detection such attacks is using information from the last few connections. Finally, proposed detection method results are further described.

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The goal of the thesis was an analysis of IoT communication protocols, their vulnerabilities and the creation of a suitable anomaly detector. It must be possible to run the detector on routers with the OpenWRT system. To create the final solution, it was necessary to analyze the communication protocols BLE and Z-Wave with a focus on their security and vulnerabilities. Furthermore, it was necessary to analyze the possibilities of anomaly detection, design and implement the detection system. The result is a modular detection system based on the NEMEA framework. The detection system is able to detect re-pairing of BLE devices representing a potential pairing attack. The system allows interception of Z-Wave communication using SDR, detection of Z-Wave network scanning and several attacks on network routing. The system extends the existing detector over IoT statistical data with more detailed statistics with a broader view of the network. The original solution had only Z-Wave statistics with a limited view of the network obtained from the Z-Wave controller. The modular solution of the system provides deployment flexibility and easy system scalability. The functionality of the solution was verified by experiments and a set of automated tests. The system was also successfully tested on a router with OpenWRT and in the real world enviroment. The results of the thesis were used within the SIoT project.

The thesis describes a design and implementation of Nemea system module purposed on generation of records about simulated network attacks. This thesis also contains brief description of Nemea system and several network attacks. Finally, part of this work is description of simulated attacks and methods of simulations.

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Malgré leurs divisions politiques, les Grecs reconnaissaient l’existence de sanctuaires qui leur étaient communs. Or, à côté de leurs fonctions religieuses, ces grands sanctuaires jouèrent aussi un rôle indéniable dans la politique internationale aux Ve et IVe siècles avant notre ère. En effet, les quatre plus grands, les sanctuaires de Delphes, de l’Isthme, de Némée et d’Olympie, organisaient des concours panhelléniques et recevaient des offrandes venues de tout le monde grec. Certes, les sanctuaires communs pouvaient aussi rassembler tout ou partie des Hellènes, dans le cadre de koina ou d’alliances militaires, mais ils étaient avant tout des lieux de mise en scène des rivalités entre les États grecs. C’est pourquoi ceux-ci cherchèrent à exercer un contrôle plus ou moins direct sur eux. Ainsi, lorsque le caractère commun du lieu sacré s’était traduit par la mise en place d’institutions, celles-ci pouvaient voir s’exprimer des rapports de force entre les différents membres. Surtout, en particulier dans le cas des sanctuaires se situant sur des confins, la volonté de maîtriser des sanctuaires communs pouvait donner lieu à des conflits mêlant politique et religion, le contrôle d’un sanctuaire étant alors la clé de l’hégémonie sur la région dont il était le centre cultuel. Néanmoins, les grands sanctuaires ne furent pas que des enjeux entre puissances  : les oracles et les familles sacerdotales qui y étaient responsables du culte pouvaient incontestablement prendre position dans les luttes pour l’hégémonie en Grèce. De plus, ces sanctuaires pouvaient parfois servir d’interfaces entre la civilisation hellénique et les cultures voisines (Perses, Étrusques, Libyens…). / Despite their political divisions, Greeks knew the existence of sanctuaries who were common to them. However, in addition to their religious functions, these great sanctuaries played too an undeniable in international policy in the 5th and 4th centuries BC. The four greatest sanctuaries (Delphi, Isthmia, Nemea and Olympia) organized panhellenic games and received consecrations from all the Greek world. Moreover, common sanctuaries could gather all the Hellenes or a part of them in koina or military alliances, but they were above all places for rivalries between Greek states. That is why these tried to control them more or less directly. Thus, when the common characteristics of the sacred place had resulted in specific institutions, these could be the scene of conflicts between different protagonists. Above all, particularly with sanctuaries on the borders, the will of control of great sanctuaries coul result in both political and religious wars. The control of a sanctuary was then the key of the hegemony on the country of which it was the religious center. Nevertheless, great sanctuaries were not only stakes between powers: oracles and priestly families who were in charge of the temple could unquestionably intervene in struggles for hegemony in Greece. Moreover, these sanctuaries could sometimes be places of contact between Hellenic civilization and neighbouring cultures (Persians, Etruscans, Libyans, etc.).

The aim of this master's thesis is to design a language through which it would be possible to monitor a stream of network flows in order to detect network policy violations in the local network. An analysis of the languages used in the data stream management systems and an analysis of tasks submitted by the potential administrator were both carried out. The analysis specified resulted in the language design which represents pipelining consisting of filtering and aggregation. These operations can be clearly defined and managed within security rules. The result of this thesis also results in the Policer modul being integrated in the NEMEA system, which is able to apply the main commands of the proposed language. Finally, the module meets the requirements of the specified tasks and may be used for further development in the area of monitoring network policies.