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Wireless IR sensor for space intrusion detection
Možný, Radek ; Krajsa, Ondřej (referee) ; Škorpil, Vladislav (advisor)
The bachelor thesis deals with design of wireless space breach detection sensor using sensor HC-SR501 and communication module SI4432. In thesis emphasis is on design of device with as low power consumption as possible using sleep modes of microprocessor Atmega328. Thesis includes desighn of temperature measurement, battery state measurement and subsequent broadcasting of gained information to receiving base station. Task of basae station is to evaluate information and among other things decide whether or not is guarded space breached. Two sensor network is further elaborated when sensors are sending periodical notification, person detection alarm, sensor manipulation alarm or warning about low battery state. Base station has regimes guarded and unguarded .
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Design and development of application for position monitoring
Kovář, Petr ; Šilhavý, Pavel (referee) ; Krajsa, Ondřej (advisor)
The aim of the master’s thesis was to implement in the C++ language a software solution of the localization of the mobile phone with Symbian OS in the GSM network. The intended purpose of this solution would be especially the phone localization in the case of its theft or loss. A familiarization with the development process of the Symbian platform and understanding the features of the Symbian version of the C++ language preceded the realization itself, because the Symbian C++ has an original style of the memory manipulation and error handling. The Symbian C++ basic principles and its features used in the implemented software are described in the second chapter of the text part, the first chapter deals with the history and version structuring of the Symbian OS. In the third part of the text is described the created software. The realized solution consists of three parts – server application PhoneLocServer for a mobile device, client application PhoneLocClient for a PC and the web-located part. The server was developed for the Symbian OS in the C++ language in the IDE Carbide.c++ and was tested in the S60 3rd edition SDK MR emulator and on the real device Nokia N73. It is a GUI-less application running in the background, which is run automatically after a smartphone start-up. It controls the incoming SMS over the socket listening and the messages addressed to itself processes before a user can notice them. The control messages body is comprised of a prefix, which identifies them, a password, a sending period value and a state to which application should change. After the receiving of the control SMS server verifies the SMS sender through the use of his telephone number and the password. It compares these values with the data stored for the given IMEI on the web server. If the verification succeeds, the server runs a timer with the period known from the control SMS and on the callback of this timer are transferred the data describing current phone location and state via HTTP protocol to the web server. The GSM localization method “Cell ID” is used for the location determination. After the client user asks for the start of loading the data, he must answer the password and the observed phone’s IMEI and he is verified through the use of the web server again. If the verification succeeds, the periodic download of the server data starts and from the first downloaded file is found out the upload period. Download then continues till the time the client detects the end of sending by the server part or till the client user stops the download himself. The client was developed in the C++ language in the C++ Builder environment. It requires a Windows OS and internet connection for its right function. The web server mediates communication between the server and the client, stores the data for user verification and makes possible the server-side upload by the help of a simple PHP script. In all the used web server directories is present the .htaccess file to improve its security, e.g. it denies the directory listing in a web browser.
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Modelling of the properties of transmission channel for xDSL systems
Nepovím, Pavel ; Číž, Radim (referee) ; Krajsa, Ondřej (advisor)
The aim of the thesis is introduce problems of the modelling transmission properties of the metallic symetric cables that are always the most often transmission cables on access networks where the xDSL systems are installed. At first the structual features of the metallic symetric cables, theirs transmission properties (primary and secondary) and models of these parametres are shown. Then the ABCD transmission parameters that characterized the transmission line as a two-port network are described, by force of that the transfer function is obtained. The aplication which was created in Matlab offers to check of the theoretical knowledges . This aplication makes it possible to choose the character of transmission line and to approximate the obtained transfer function of this transmission line.
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Protection of VoIP networks and their testing
Ulický, Ivan ; Sysel, Petr (referee) ; Krajsa, Ondřej (advisor)
Main goal of creating this diploma thesis is existence of increasingly amount of potential threats against IP voice networks (VoIP). The thesis is devoted to testing of various types of attacks and provides some possible solutions for this systems as well. The work points out to a various types of current attacks against either insecure or very little secure structures. The theoretical part is dedicated to analyse and description of wide spectrum of VoIP protocols including signaling protocols (SIP, IAX2), transport protocols (RTP, RTCP) and security protocols (SRTP, ZRTP, IPsec, SDES). Further attention is dedicated to the one of possible open source IP PBX solutions called Asterisk. There is shown a variety of possible attacks against this system due to its openness, because open systems always tend to be more susceptible for various attacks as they need an advanced administration and endless need for searching of new trends in area of security. The last block of the theoretical part is focused on common threats and types of attacks against VoIP networks. The practical part is about design and creation of web application called ,,VoIP Hacks using PHP” written in PHP scripting language and ist main task is to execute three basic attacks: eavesdropping, call drop and call flood. There is also a possibility of port scanning of selected network which is added as supplementary part of this application. The application can be comfortably managed from web browser user interface. All captured data can be displayed directly into the web browser. Tests of the application were performed on Google Chrome and Mozzila Firefox browsers. There is an accent placed on cooperation between the application and terminal linux programmes such as Tshark, BYE Teardown, INVITE flooder or Nmap, which all accept commands from web interface and interpret gained output values back to the web browser.
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Comparison of SIP implementations used in Asterisk and Kamailio open source PBX's
Rajj, Jakub ; Krajsa, Ondřej (referee) ; Šilhavý, Pavel (advisor)
The diploma thesis deals with the comparison and testing of private branch exchanges Asterisk and Kamailo. It also deals with the comparison of stack SIP and PJSIP. At the beginning of the thesis, there is a theoretical part describing private branch exchanges, SIP protocol and PJSIP. In the next section, the tested PBXs Asterisk and Kamailio are described and there is comparison of it´s functions. The private branch exchanges are installed, configured and tests are performed using the Spirent Testcenter C1. The results of the tests were processed into graphs and at the end there is a discussion about the results.
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Modernization of the master clock for slave clocks controlling
Pokorný, Jiří ; Číž, Radim (referee) ; Krajsa, Ondřej (advisor)
This diploma thesis describes modernization of the master clock HN 50 created by company ELEKON, s.r.o. Master clock can be used for controlling of analog or digital slave clock or for switching school bells. Exact differences between old and new version of the clock are described and ways of synchronization and controlling of slave clock are explained. Main goal of modernization is applying the SMT technology for automation of production. Another problems and shortcomings of previous version are developed, such as new power supply structure, selection of a new microcontroller and usage of several different displays. Every problem is developed and new solutions are chosen. Last part of the document describes the software which is clarified on several flowcharts. Outputs of the thesis are complete schematics, printed circuit boards and 3D models of the modernized device.
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Digital voice communication network with status indication
Pobiecky, Michal ; Šilhavý, Pavel (referee) ; Krajsa, Ondřej (advisor)
The main focus in this diploma thesis is to analyse ARM microcontroller ATSAM3X8E, audio codec TLV320DAC3203 and CAN / RS485 bus for communication possibly used in device design. This device's purpose is to establish communicatio between elevator cabin and central control unit. Finally, there is design made for this communication device and measurement of CAN bus speed on H05VVH6 cable.
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Narroband PLC model
Sekot, Karel ; Krajsa, Ondřej (referee) ; Mišurec, Jiří (advisor)
This thesis is focused on data communication utilizing low-voltage power distribution lines (PLC). It describes interference in narrowband systems commonly used for remote data collecting, for example. Preamble deals with basic priciples of PLC (signal injecting) and describes the measuring workplace, its wiring and used tools. Following sections define different types and possible sources of interference, operation of the equipment in terms of EMC and other characteristics of the transmission path. The text also analyzes practical interference tests, identifies main parameters affecting data transmision and compares teoretical and practical conclusions.
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