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System for automatic evaluation of email messages
Frkal, Jan ; Červenka, Vladimír (referee) ; Koutný, Martin (advisor)
This diploma thesis deals with the design and realisation of system for automatic evaluation of e-mail messages. The system works with PHP language and MySQL database. It also allows automatic synchronisation. During the synchronisation e-mail messages are downloaded and saved using IMAP or POP3 protocol. Subsequently, the messages are analysed. During the analysis the reports are classified into types, according to pre-defined keywords. The system also works with black lists and white lists. If the sender of an e-mail is during the synchronisation found in the blacklist, that e-mail will be skipped. On the contrary, if the sender of an e-mail is found within the white list, that e-mail will be excluded from keyword matching and from the list is type and category loaded. Most of the values from the carried out evaluation of the e-mails can be clearly seen in advanced statistics. Pie charts and numerical statistics are available. Access to the system is protected by a login. Therefore, login can only registered users.
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Assesment of the meaning of Polarization Mode Dispersion
Červenka, Vladimír ; Rampl, Ivan (referee) ; Kyselák, Martin (advisor)
This thesis describes the most important types of distortions in fibre optics during transmission. They are divided into two main groups, linear and nonlinear. The linear phenomena consist of internal and external attenuation, different kinds of dispersions and negative effect of signal noise. The special attention is focused on polarization mode dispersion. The impact of the nonlinear phenomena on fibre optics in high date rate is discussed as well. Furthermore, the negative effects in fibre optics and their causes are deeply analyzed on results gathered from simulation of some transmission lines. There are presented many methods for counting the meaning of polarization mode dispersion, for example the theoretical model including implementation on physical layer and reducing power looses. Some examples of designing fibre optic lines are introduced along with calculation for them.
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Design and management of WDM systems for optical networks
Červenka, Vladimír ; Šporik, Jan (referee) ; Tejkal, Vladimír (advisor)
This thesis describes single types of wavelength-division multiplex (WDM) according to the International Telecommunication Union (ITU-T). This work offers an overview of components and evaluation of critical parts of network design utilizing WDM technology. There are depicted typical properties, suitable components and channel spacing for each category. Suitable optic fibers according to ITU-T and characteristics of negative effects can be found in the work as well. Furthermore, there are presented most important optic sources, optic amplifiers, optic detectors with filters their requirements and application. They are especially important for achieving operation of WDM system. The fifth chapter considers impact of negative effects in fiber optics and their influence on the system. Then, a WDM system is designed along with management and monitoring the physical layer. The work also presents 1,33 Tbit/s (32 × 42,7 Gbit/s) WDM transmission over 300 km (with three 100 km spans) of post-compensated non-zero dispersion-shifted fiber (NZDSF) LEAF. The capacity of 400 Tbit/s×km is achieved in a single 25,6 nm C band using non-return-to-zero differential phase-shift-keyed modulation (NRZ-DQPSK), balanced detection and erbium-doped fiber amplification. Together with design of transmission system a several simulative analysis has been carried out in order to find the optimum configuration (such as number and distances between amplifiers, length of spans or the way of dispersion compensation) for a high bit rate optical transmission system. It was used a program OptiSystem 8.0.
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Implementation of Honeypot tool for monitoring and analysis of network attacks
Němeček, Ladislav ; Červenka, Vladimír (referee) ; Bartl, Milan (advisor)
The goal of this thesis is to describe and categorize the malicious software. Thesis deals with the network attacks and the protection against them as well as how to detect and analyze the attack by the eligible tools. The next part of the thesis deals with the honeypot topic and the possibilities of detection using this software, specifically then the Argos tool. The installation, usage, and the methods of detection of the tool are also being described. The next chapter describes how to secure the honeypot against abuse. Last but not least, the thesis also contains the results of the network monitoring, attacks on the honeypot, and describes the log files used by Argos to interpret the results of the attack detection.
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Impact of Communication Parameters on Energy Consumption of Zigbee Devices
Popelka, Jan ; Červenka, Vladimír (referee) ; Šimek, Milan (advisor)
This thesis deals with the energy research and design a simple wireless sensor networks. The data modules with ZigBee wireless communication technology. The main feature of wireless sensor networks is the minimal energy devices at low cost and maximum data reliability. Furthermore, the work describes firmware for communicating nodes with the ability to change parameters of data transmission and thus affect the energy consumption node. Calculations of energy consumption, compared with measured results and discharge characteristics of the battery packs are included in the final chapters of this work.
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Monitoring of communication properties in Internet
Iľko, Pavol ; Červenka, Vladimír (referee) ; Komosný, Dan (advisor)
This thesis deals with measuring transmission parameters of the Internet network, in particular latency of ping, SSH protocol and bandwidth. The thesis is divided into a theoretical and a practical part. Theoretical part describes PlanetLab network, its brief history and contemporary projects. At the same time, tools for data mining from web pages are described. These information obtained from the theoretical part are used for creating PlanetLab nodes list and for programming applications which measure the network transmission parameters. Applications, list of nodes and obtained data are attached on DVD disc.
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Website Design
Dlasková, Jana ; Červenka, Vladimír (referee) ; Koch, Miloš (advisor)
This thesis describes the design and creation of web sites for kindergarten. The goal is to create a functional and dynamic website which will reflect the nature of kindergarten. Website will serve mainly to parents of children.
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Over the Air Firmware Upgrade for Wireless Sensor Networks
Minár, Tomáš ; Červenka, Vladimír (referee) ; Mráz, Ľubomír (advisor)
This diploma thesis is dedicated to one of the problems in wireless sensor networks – over the air upgrade (OTAU) of nodes. The requirements for upgrade and possible ways how to transfer new firmware image to nodes are stated in the first chapter. The second chapter is focused on solving the problem of firmware dissemination to whole network based on analysis of known protocols. The practical part of this thesis deals with OTAU design and implementation in Lightweight Mesh software stack from Atmel. Proposed system was tested on deRFnode platform with plugged in deRFmega128 module. The upgrade process of designed system is evaluated on test network in last part. Practical test results are compared with OTAU solution for BitCloud.
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Energy demands of localization algorithms
Maňák, Jiří ; Červenka, Vladimír (referee) ; Morávek, Patrik (advisor)
This masters thesis deals with technics of localization for wireless senzor networks with a focus on anchor free location algorithm by authors G. Jianquan and Z. Wei. It also describes the available simulations frameworks based on OMNeT++ platform and implementation of the anchor free algorithm in the simulation program Castalia. Furthermore, it deals with the energy demands of this algorithm based on results of simulations that were done for the communication unit IRIS.
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