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Contact Synchronization for a Private Cloud
Sendler, Jaroslav ; Očenášek, Pavel (referee) ; Trchalík, Roman (advisor)
This masters's thesis is studying the possibility of Create a synchronization tool for device running on Android. It is the ability to sync contacts from portable devices in a private cloud, which is here substituted by Directory server. For working with directory, server uses LDAP server and its implementation of OpenLDAP. The first part is aimed at the description of the structure and directory services. Following is analysis and separation requirements. The whole project is completed by proposals and implementation that relate to the safety and advanced synchronization.
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Extraction of Decrypted Data from SSL Connection
Pastuszek, Jakub ; Veselý, Vladimír (referee) ; Grégr, Matěj (advisor)
Cílem této práce je vyvinout aplikaci schopnou dešifrovat zabezpečená spojení a přeposlat dešifrovaná data na jinou stanici v síti pro další analýzu. Daná aplikace vybízí k nelegálním účelům, avšak zamýšleným použitím výsledného produktu jsou legální odposlechy. Pro tuto práci byla z množiny nástrojů vybrána aplikace SSLsplit díky jejím vlastnostem a výkonnosti. Toto rozhodnutí bylo na základě srovnávacích testů a porovnání vlastností. Pomocí vlastního certifikátu SSLsplit podepisuje certifikáty cílových serverů, které jsou vytvářené za běhu. Spuštěná aplikace běží v režimu transparentní proxy přímo na centrálním prvku dané sítě (routeru). SSLsplit provádí man-in-the-middle útok mezi klientem a serverem bez toho, aby to některá ze stran zaznamenala. Dále umožnuje dešifrovaný obsah odeslat na předem daný uzel v síti pro jeho další zpracování. Pro možnost snažší konfigurace SSLsplitu byla implementována integrace do netc rozhraní. Aplikace byla otestována za účelem zjištění jejich výkonnostních limitů. Výkonnostní testy výsledného řešení ukazují značný pokles počtu transakcí za sekundu (TPS) při použití SSLsplit v porovnání s pouhým přeposíláním provozu. Funkce zrcadlení významně neovlivňuje počet TPS ani neomezuje samotný SSLsplit. Výsledky ukazují, že SSLsplit je schopen reálného provozu s určitým omezením.
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Safe Cryptography Algorithms
Zbránek, Lukáš ; Schäfer, Jiří (referee) ; Chmelař, Petr (advisor)
In this thesis there is description of cryptographic algorithms. Their properties are being compared, weak and strong points and right usage of particular algorithms. The main topics are safeness of algorithms, their bugs and improvements and difficulty of breaching. As a complement to ciphers there are also hash functions taken in consideration. There are also showed the most common methods of cryptanalysis. As a practical application of described algorithms I analyze systems for secure data transfer SSH and SSL/TLS and demonstrate an attack on SSL connection. In conclusion there is recommendation of safe algorithms for further usage and safe parameters of SSH and SSL/TLS connections.
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Analysis of Mobile Devices Network Communication Data
Abraham, Lukáš ; Bartík, Vladimír (referee) ; Burgetová, Ivana (advisor)
At the beginning, the work describes DNS and SSL/TLS protocols, it mainly deals with communication between devices using these protocols. Then we'll talk about data preprocessing and data cleaning. Furthermore, the thesis deals with basic data mining techniques such as data classification, association rules, information retrieval, regression analysis and cluster analysis. The next chapter we can read something about how to identify mobile devices on the network. We will evaluate data sets that contain collected data from communication between the above mentioned protocols, which will be used in the practical part. After that, we finally get to the design of a system for analyzing network communication data. We will describe the libraries, which we used and the entire system implementation. We will perform a large number of experiments, which we will finally evaluate.
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Cryptography on an embedded platform
Korenčiak, Peter ; Hynčica, Ondřej (referee) ; Fiedler, Petr (advisor)
This bachelor thesis deals with adjusting parts of the public domain cryptographic library LibTomCrypt so that it can be used on an embedded platform Rabbit 3000. The hash functions MD5, SHA-1 and RIPEMD-128, the Blowfish cipher and CBC block cipher mode have been successfully ported to this platform. These algorithms have been analysed by measuring of the exectution time for the computational power requirements, especially with regard to the length of the input data. The abovementioned hash functions showed non-linear relationship between the execution time and the length of input, the graph of which is like that of a step function. The non-existence of the relationship to the data values was confirmed. The measurements with Blowfish cipher in CBC block cipher mode showed that inicialization of cipher is time consuming (it lasted almost one second on the hardware used) and that it does not depend on the keysize or length of input. The encryption and decryption itself showed a linear relationship to input data length. In the scope of this thesis there was also verification of correct function of SSL/TLS library from the producer of Rabbit microprocessor by creating a HTTPS server and verifying that secure connection with the web browser has been established. The library worked correctly according to manual without any significant problems.
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Secure peer-to-peer communication system
Eliáš, Luboš ; Koutný, Martin (referee) ; Cvrk, Lubomír (advisor)
The main aim of this master's thesis is to implement a common, secure and peer-to-peer communication system. The system has ability to automatically establish and run a secure end-to-end connection. It has this ability even if a network address translator is in the way to the destination system, without need of any explicit configuration of this translator. The security procedures of this system are in a transparent manner masked from individual applications, which had to solve this challenge in their own way. A responsibility for a security is delegate to an application-independent subsystem working within the core of an operating system. The security of this subsystem is based on capturing the outbound and inbound IP packets and their authentication and encryption. The system was successfully implemented in MS Windows XP operating system, in programming language C++. Transfer rate of communication tunnel in different network bandwidth speeds was measured. Result shows, that in the case of use the system on standard PC sold nowadays is practically no decrease of the transfer rate in comparison to a common channel.
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Secured access for web applications
Humpolík, Jan ; Pelka, Tomáš (referee) ; Doležel, Radek (advisor)
This thesis mainly concerns often neglected security part of each web application, but also secure access users themselves. Describes theoretically and practically modern security technology, on a web application being tested and shows a possible way of defense. Gives instructions for installing its own web server.
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Analysis of Mobile Devices Network Communication Data
Abraham, Lukáš ; Bartík, Vladimír (referee) ; Burgetová, Ivana (advisor)
At the beginning, the work describes DNS and SSL/TLS protocols, it mainly deals with communication between devices using these protocols. Then we'll talk about data preprocessing and data cleaning. Furthermore, the thesis deals with basic data mining techniques such as data classification, association rules, information retrieval, regression analysis and cluster analysis. The next chapter we can read something about how to identify mobile devices on the network. We will evaluate data sets that contain collected data from communication between the above mentioned protocols, which will be used in the practical part. After that, we finally get to the design of a system for analyzing network communication data. We will describe the libraries, which we used and the entire system implementation. We will perform a large number of experiments, which we will finally evaluate.
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Contact Synchronization for a Private Cloud
Sendler, Jaroslav ; Očenášek, Pavel (referee) ; Trchalík, Roman (advisor)
This masters's thesis is studying the possibility of Create a synchronization tool for device running on Android. It is the ability to sync contacts from portable devices in a private cloud, which is here substituted by Directory server. For working with directory, server uses LDAP server and its implementation of OpenLDAP. The first part is aimed at the description of the structure and directory services. Following is analysis and separation requirements. The whole project is completed by proposals and implementation that relate to the safety and advanced synchronization.
|
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Extraction of Decrypted Data from SSL Connection
Pastuszek, Jakub ; Veselý, Vladimír (referee) ; Grégr, Matěj (advisor)
Cílem této práce je vyvinout aplikaci schopnou dešifrovat zabezpečená spojení a přeposlat dešifrovaná data na jinou stanici v síti pro další analýzu. Daná aplikace vybízí k nelegálním účelům, avšak zamýšleným použitím výsledného produktu jsou legální odposlechy. Pro tuto práci byla z množiny nástrojů vybrána aplikace SSLsplit díky jejím vlastnostem a výkonnosti. Toto rozhodnutí bylo na základě srovnávacích testů a porovnání vlastností. Pomocí vlastního certifikátu SSLsplit podepisuje certifikáty cílových serverů, které jsou vytvářené za běhu. Spuštěná aplikace běží v režimu transparentní proxy přímo na centrálním prvku dané sítě (routeru). SSLsplit provádí man-in-the-middle útok mezi klientem a serverem bez toho, aby to některá ze stran zaznamenala. Dále umožnuje dešifrovaný obsah odeslat na předem daný uzel v síti pro jeho další zpracování. Pro možnost snažší konfigurace SSLsplitu byla implementována integrace do netc rozhraní. Aplikace byla otestována za účelem zjištění jejich výkonnostních limitů. Výkonnostní testy výsledného řešení ukazují značný pokles počtu transakcí za sekundu (TPS) při použití SSLsplit v porovnání s pouhým přeposíláním provozu. Funkce zrcadlení významně neovlivňuje počet TPS ani neomezuje samotný SSLsplit. Výsledky ukazují, že SSLsplit je schopen reálného provozu s určitým omezením.
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