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Performing a Relay Attack on Mifare Smart Cards
Činčala, Martin ; Henzl, Martin (referee) ; Malčík, Dominik (advisor)
This thesis deals with performing a relay attack on MIFARE smartcards while using off-the-shelf readers only. These readers are not designed for such attacks therefore implementation of the attack that would succeed against every smartcard was not possible. Since various attacks on smartcards have already been implemented, I have focused on the latest and still insufficiently explored card MIFARE Ultralight C. Relay attack has been implemented with simplified emulation of 4-bytes long UID and successfully tested on MIFARE Ultralight C. With the use of other readers it should be possible to perform attack also on other cards like MIFARE Plus, Desfire and SmartMX. For the purpose of cloning MIFARE Classic open-source tools are introduced.
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Node localization on the Internet using domain name system
Dvořák, Petr ; Müller, Jakub (referee) ; Komosný, Dan (advisor)
This paper describes various systems that are used to predict delay among nodes . It focuses on systems using for prediction delay artificial coordinate systems, and on the systems, which use physical measurements of delay. Primarily, however, it deals with the King method, which uses the system for translation of domain names - DNS (Domain Name System) to predict the delay. Next, the principle of the King method is outlined in detail. Practical part includes a description of the two created simulations in program Matlab. The first application described simulates the King method principle. The second simulation is then tasked with creating 2D geometric space in which nodes and DNS servers are randomly generated. The result is dependence of RTT prediction accuracy on the number of randomly generated DNS servers. Based on this dependency the method King is compared with other methods in the end.
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Implementation of video compression into FPGA chip
Tomko, Jakub ; Fujcik, Lukáš (referee) ; Bohrn, Marek (advisor)
This thesis is focused on the compression algorithm's analysis of MJPEG format and its implementation in FPGA chip. Three additional video bitstream reduction methods have been evaluated for real-time low latency applications of MJPEG format. These methods are noise filtering, inter-frame encoding and lowering video's quality. Based on this analysis, a MJPEG codec has been designed for implementation into FPGA chip XC6SLX45, from Spartan-6 family.
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Optimalization and analysis of communication services latency dependencies
Zikmund, Lukáš ; Škorpil, Vladislav (referee) ; Endrle, Pavel (advisor)
This master’s thesis is focused on ensuring of Quality of Service (QoS) in wireless network for standards IEEE 802.11 a/b/g/n. First part of this thesis is focused on the theory of this issue. It covers methods of data transfer in computer networks and individual transfer parameters especially on parameters needed to ensure quality of service. It also describes standards for wireless data transmission and protocols for real time data transmission. The second part is devoted to OPNET modeler and to simulations created on this program. Simulations are focused on real-time data transfer and compare the standards in terms of delay and jitter.
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Geolocation of Internet nodes based on communication latency
Horák, Michael ; Balej, Jiří (referee) ; Komosný, Dan (advisor)
This thesis covers the topic of determination of geographical location of a host in internet network while utilizing measurement of the end to end delay and implementation of Constraint-Based Geolocation. Gradually I go through issue of the delay in computer networks and ways how to measure it. Next chapter describes a few ways to geolocate host in internet network with emphasis on the CBG method. Another chapter is dedicated to describing a way to project spherical coordinates to the two dimensional space, which has been used in implementation of geolocation method. Chapter about implementation builds upon the facts given in previous chapters while functions of the program written in the JAVA programing language are being explained. Two similar geolocation methods were implemented. By comparing the results gained by implementation, new method of geolocation is proposed and devised. It combines properities of both previous methods. There are results of the implemented methods and their comparation to the one of the source documents used in creation of this thesis in summary section.
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Localization of IP stations based on model of probability delay measurement
Tropp, Peter ; Komosný, Dan (referee) ; Verner, Lukáš (advisor)
The master thesis is dealing with Internet host localization methods, more exactly with determining geographical position of the unknown Internet host connected to the network using RTT delay measuring. The first part is dealing with description of RTT delays that may occur in the network and tools for their measurement. The next is part of thesis is devoted to description of two kinds of localization methods. Ones that are using existing data to determine the position of Internet host also called passive methods, and others that are using RTT delay measurement, also called active methods. The main part is focused on GeoWeight method which is based on geographical localization estimation of Internet host. It is based on RTT delay measurement using the principles of CBG method, enhanced by introduction of the theory of weights according to the probability of the target Internet host. The last part is describing the application that was made to determine the geographic localization of the target Internet host using GeoWeight method. The application was afterwards tested by measuring RTT delay in PlanetLab experimental network. At the end the final measured results were compared with other localization methods (CBG, Octant, SOI, GeoIP).
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Geolocation in Internet using latency measurements
Harth, Petr ; Balej, Jiří (referee) ; Komosný, Dan (advisor)
This diploma thesis is concerned with practical realization of CBG (Constraint-based Geolocation) algorithm, which is one of the IP (Internet Protocol) geolocation technique. IP geolocation determines the localization of a computer workstation location on the basis of on its IP address. The factors causing delays in data transfer are discussed first, followed by discussion of the issue of measuring these delays. The detailed explanation of IP geolocation follows where its contexts as well as the active geolocation techniques (techniques based on delay measurement mentioned above) are described. After that a brief description of PlanetLab experimental network, which was used for geolocation techniques measuring, is presented followed by a section explaining the creation of reference points and targets, which are another necessary prerequisite for practical realization of the method. Then the practical realization is explained in the form of CBGfinder program and its verification on the basis of artificial input data along with an actual example of IP geolocation of a point in the Internet are provided. Last but not least the measurement results of CBG algorithm are introduced, based on the analysis of Bestline parameters of one of the PlanetLab nodes measured in the period of one month, followed by a discussion of the inaccuracy of geological position and the computation speed. The cumulative distribution function as well as the kernel density estimation are also described. Final part of the thesis consists of discussion on measured results compared to results of other geological techniques results implemented by colleagues of the author of this diploma thesis. The results are compared on the basis of average inaccuracy of geological position estimations and its median, computation time, cumulative distribution function and kernel density estimation are also taken into regard.
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Localization of nodes in Internet using King system
Exler, Michal ; Müller, Jakub (referee) ; Komosný, Dan (advisor)
This thesis is focus on problematics of nodes localization in Internet. There are describe methods for prediction latency by using artificial coordinates systems and by using direct measurement. This thesis is primarily focus on method names King, which is estimates latency between arbitrary end hosts by using recursive DNS queries in system for translate domain name.
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Mobile IPv6 handover analysis
Klügl, Richard ; Hošek, Jiří (referee) ; Skořepa, Michal (advisor)
This master’s thesis is focused on IP mobility support for mobile users and their devices in IPv6-based wireless networks. Then the Mobile IPv6 (MIPv6) protocol was proposed for this purpose and that is also the main objective of the thesis. This consists of several basic sections and is organized as follows: The first one deals with the overview of the function of Mobile IP, which enables the mobility of nodes around the Internet, without a change of their original IP address. Moreover there are introduced the primary differences between MIPv6 and its previous version – i.e., MIPv4, proposed for IPv4-based environment. The second chapter of the master’s thesis thereafter describes detailed information about all the most important mechanisms and features of Mobile IPv6 and this way tries to explain principles of its functioning. Further the thesis analyses some of proposed MIPv6 extensions – i.e., Hierarchical Mobile IPv6 (HMIPv6), Mobile IPv6 Fast Handover (FMIPv6) a Fast Handover for HMIPv6 (F-HMIPv6) protocols, and mainly aim at signaling process during the handover of a mobile node. In the last main section of the master’s thesis an analytical method to evaluate the performance of IPv6-based mobility management protocols was proposed. Subsequently, this method is applied on the protocols which were mentioned above and are studied the effects of various network parameters on the performance of these protocols.
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Analysis of the effect of delay and window size on TCP connection efficiency
Kavický, Martin ; Komosný, Dan (referee) ; Molnár, Karol (advisor)
Content of master’s thesis is description field of Sliding window and it’s expansion algorithms, witch are Slow start, Congestion avoidance, Fast Retransmit and Fast Recovery algorithm. Thereinafter is described creation of model in Opnet Modeler’s simulation area. In this simulation area was analyzed reactions of average transfer speed onto variance of data size, lost ratio, latency in short and long time slot and variance of receiver’s buffer size. In last section of this document is method design witch makes it possible of transfer speed control through the use of receiver’s buffer size dynamic setting.
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