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Possibilities of connecting the Asterisk softswitch to the 4th generation PBX
Halamík, Zdeněk ; Krajsa, Ondřej (referee) ; Šilhavý, Pavel (advisor)
This master’s thesis dissertate the possibilities of the linkage between Asterisk softswitch and the 4th generation private branch exchange. This should create a new generation’s network, so-called NGN, by the convergence of existing telecommunication networks with an IP computer network. This master’s thesis is divided into several chapters. In introduction is described the evolution of the private branch exchanges as well as the principles of the voice digitizing, codecs and signaling commonly used in both TDM and VoIP networks. The main aim of this project is the configuration of Asterisk software exchange for connection with PBX Alcatel 4400 as well as public phone network PSTN. Another goal of this master’s thesis was the configuration of Alcatel PBX and diagnostics of CCS and CAS signaling on E1 interface. In conclusion there are summarized advantages of NGN networks and their utilization in the future.
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Design of digital switching field animation
Kučerka, Daniel ; Šilhavý, Pavel (referee) ; Kapoun, Vladimír (advisor)
This thesis describes types and parameters of memories used in communication engineering. The memory is a device which is able to record and to save information for the certain period of time. The memory is used in computers, measuring devices, consumer electronics etc. Main parameters of the memory are capacity, data stream speed, price of bit and time of memory cycle. The first part of this thesis deals with two types of memory – external and internal. External memories are removable media such as discs and magnetic tapes used for information saving and data backup for longtime period. Inner memories – in the form of semiconductive components – are mostly attached to the main panel. There are two types of inner memories – RAM (random access memory) and ROM (read only memory). The memories could be further divided according to their dependence on feeding used for memory saving. Types of memories used in switching exchanges are also mentioned in this part. The next part discusses the scheme of T switch for the first level of European PDH E1. The space switch and the time switch T belongs to switches used in digital switching exchange. In this part, the T switch, in particular the switch TR with controlled reading and the switch TW with controlled writing are described into details such as its parameters and methods of control. Furthermore, the calculation of call memory and control memory extant in E1 and E2 hierarchy are presented as well as the memory reading time and writing time of T switch in E1 and E2 hierarchy. The result of this thesis is a design of digital switching field animation that consists of four T switches. All operations, which are used in building linking of digital switching field, are shown in this animation.
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Procedure for the application of a high-speed VDSL2 technology
Coufal, Tomáš ; Šilhavý, Pavel (referee) ; Novotný, Bohumil (advisor)
A bachelor thesis sums up the basic line parameter, it deals with VDSL2 technology and G.fast. The work describes its attributes, profiles, masks and also an utilisation of vectoring. There is a comparation with other used technologies in this work. The last part is focused on simulations which are comparing different types of DSL connections and on an influence of vectoring to achievable effective distance.
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IoT system for conference room control
Kondás, Peter ; Šilhavý, Pavel (referee) ; Krajsa, Ondřej (advisor)
The goal of this bachelor´s thesis was to design and implement a system for monitoring room occupancy by counting the entries and exits of individuals from the room and chair occupancy detection, with the system sending data using the MQTT protocol. A device was designed for the system and components and sensors were then selected to further expand its capabilities. Home Assistant was used as the user interface for this system, providing a clear representation of the current state of the conference room.
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Broadband over powerline modem
Mahút, Michal ; Šilhavý, Pavel (referee) ; Musil, Petr (advisor)
The aim of the diploma thesis is to look into the issues of Broadband Over Powerline Communication, design and construct a BPL modem. The theoretical part of the thesis covers the division and description of Powerline Communication, its standards, and factors affecting communication over electrical wiring. The practical part includes the design of a printed circuit board for the BPL modem with the selection of necessary components for the modem construction. The output of the thesis is a constructed broadband PLC modem, whose transmission properties and interference resistance are compared with commercially available solutions.
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Power over Ethernet
Hykš, Matěj ; Šilhavý, Pavel (referee) ; Koton, Jaroslav (advisor)
The bachelor thesis focuses on the topic of powering network elements using Power over Ethernet shortly PoE. The work focuses more in detail on the functions of the 802.3af and 802.3at standards, which are described in detail and explains their functionality on specific examples of PD chips. Then it summarizes the measurement methodology used for 3 devices belonging to the PSE category and 4 devices from the PD category. In both cases, it focuses on their analog and digital communication.
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DSL analyzer
Hála, David ; Číž, Radim (referee) ; Šilhavý, Pavel (advisor)
This bachelor thesis is devoted to the development of an application for signal analysis using xDSL technology. The first part of the thesis describes the basics of these tech- nologies and the theoretical assumptions that can be expected in later analysis. Also the parameters measured by the resulting application are explained. The second part of the thesis is devoted to the description of the procedure and solution of the practical part of the thesis - program development. Finally, in the last chapter of the thesis, the program was tested in laboratory conditions and graphs were constructed from the results.
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Bonding, the method for increasing DSL data rate
Kratochvil, Tomáš ; Benešl, Lukáš (referee) ; Šilhavý, Pavel (advisor)
This bachelor thesis focuses on characteristics of DSL bonding technology. The basic information about DSL technologies is described at the start of theoretical part of thesis. VDSL2 technology is described more thorougfully in comparision with other DSL technologies, because in this thesis DSL bonding is applied on VDSL2 technology. Next chapter of theoretical part of thesis describes principe of DSL bonding technology. Final chapters of theoretical part of thesis describes recommendations for testing of network characteristics. Specifically these network testing recommendations are described: RFC 2544, RFC 6349 and Y 1564. The results of performed tests are presented in practical part of thesis. Tested DSL technologies are compared based on results of performed tests at the end of practical part of thesis.
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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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SIP security
Tůma, Petr ; Šilhavý, Pavel (referee) ; Ježek, Jiří (advisor)
This bachelor thesis focuses on security issues of the SIP signalling protocol. The goal was to carry out three attacks and design defences against them. The chosen attacks were a flood attack, a modified message attack and a man-in-the-middle attack. The attacks were conducted against the Asterisk PBX and the results show that some attacks were able to prevent communication between the PBX and clients. Defensive measures are described for each attack in the mitigation subchapter.
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