|
|
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.
|
|
|
Turbo codes and their applications in transmission technologies
Kuvik, Michal ; Číž, Radim (referee) ; Šilhavý, Pavel (advisor)
Purpose of this work is to clarify problems of anti-error security with the help of turbo codes. This work can be divided into two parts. In the first part we look at the theoretical aspect of features of turbo codes, their coding and at various approaches of decoding secure messages for example SOVA and MAP, also at analyzing usage of turbo codes in promising transmission technologies. Second part is focused on creating an application with the help of software Matlab and on verifying attributes of this method in this software.
|
|
|
Provisioning implementation in Asterisk open source PBX
Král, Jan ; Bartl, Milan (referee) ; Šilhavý, Pavel (advisor)
The bachelor's thesis "Implementation of provisioning service in Open source PBX Asterisk" deals with a general description of the provisioning service and the options of it's implementation in Asterisk PBX based on the capabilities of the PBX and the endpoint devices for VoIP telephony connected to it. The theoretical part of the thesis also contains a brief description of all the protocols and services needed for successful operation of the service in the particular scenario of implementation described in the thesis. A short introduction and requirements for the designed application are also described. The practical portion of the thesis is focused on instalation and setup of the Asterisk PBX and the provisioning service itself on a virtual server running the CentOS operating system. It also contains all the settings of the server, additional services run on the server, the Asterisk PBX and also the settings of the endpoint devices needed for correct operation of the service. A thorough description of the designed and developed web application for management of endpoint devices for VoIP telephony is also contained in this part.
|
|
|
The possibilities of SS7 signalling transport over IP network using YATE switch
Al-Anqari, Mhannad ; Novotný, Vít (referee) ; Šilhavý, Pavel (advisor)
This study examines the use of SS7 signaling system over IP networks by using the open source PBX YATE. At first it starts with describing the SS7 followed by an explanation of the function of each of its levels and the messages that are used within the SS7 network. The study then sheds some light on the ways of using SS7 inside IP network with the use of some protocols. It also discusses the architecture of YATE and its files, and how it is installed in Linux operating system. Finally, it describes the important files for delivering this task. The study was commenced by using two virtual machines that have two different open source PBX's which are YATE and Asterisk, and after acquiring some results by establishing communication between them via the means of SIP trunk, furthermore the study was extended to the laboratory in order to test it over real servers that have TDM cards, in order to apply the study by the means of SS7 protocols, SIGTRAN, MGCP gateway and SIP-T. The experiments have almost delivered successful communications after conducting a configuration for the files on multiple sides.
|
|
|
Simple Private Branch Exchange Implementation in OpenWRT
Stračár, Ivan ; Šilhavý, Pavel (referee) ; Bartl, Milan (advisor)
The diploma thesis deals with the system OpenWRT. Installing this system on the router Siemens Gigaset SX762. Describes how to compile and upload the simple package helloworld into this system. The package was tasked invitation simple phrase "Hello World" to the system console of OpenWRT. Package only serve to show that the system OpenWRT allows users to customize it according to their needs. After that it was installed PBX Asterisk into the system OpenWRT. Proper functioning of PBX Asterisk has been verified to make a call between two software phones ZoiPer. Furthermore, the work described telephony application programming interface (TAPI). Some of its fun- ctions, interfaces and packages needed to communicate with the system OpenWRT. In conclusion, the presented test topology and verify the operation of making calls between analog as well as softphones.
|
|
|
Remote data acquisition with the help of GSM modems based on Open AT platform
Otoupalík, Pavel ; Koutný, Martin (referee) ; Šilhavý, Pavel (advisor)
This bachelor's thesis deals with remote data acquisition with the assistance of GSM modems based on Open AT platform. The result of thesis is the realized module which servers as a converter temperature to frequency. This module is connected with Wavecom Fastrack M1306B programmable GSM/GPRS modem. They are intended for temperature measurement from 0 to 40 °C together. With the assistance Open AT platform and C programming language were created two applications. The first application sends data as temperature, date and time on remote FTP server via GSM network as GPRS data. The results of measurement are displayed on website in form of the table and graph. The second application sends a temperature measurement data via SMS message as reply to SMS message.
|
|
|
Demonstration set for basic keying techniques
Žlebek, Lukáš ; Šilhavý, Pavel (referee) ; Číž, Radim (advisor)
This thesis concerns itself with construction of a set of laboratory products, used for demonstrating the basic methods of digital modulation. The primary product, is a generator of carrier and keying signals, which generates cyclically repeated data, and a carrier signal. Another two products are ASK and BPSK modulators. The theoretical part of this thesis describes a basic summary of different kinds of modulation and the design of all the product prototypes themselves. The practical part proves the functionality of individual components of the generator and the functionality of the modulators. In the last part of this thesis, there is a proposal of the laboratory task and its sample solution.
|
|
|
Comparison of decoding algorithms of Reed-Solomon code
Šicner, Jiří ; Krajsa, Ondřej (referee) ; Šilhavý, Pavel (advisor)
The work deals with the encoding and decoding of Reed-Solomon codes. There is generally described algebraic decoding of Reed-Solomon codes, and then described four methods of decoding, namely Massey-Berlekamp algorithm, Euclidean algoritus, Peterson-Gorenstein-Zierler algorithm and the direct method. These methods are then compared, and some of them are implemented in Matlab.
|
|
|
Automation of measurement of disturbance influence on DSL modem transmission
Dvořák, Tomáš ; Šedý, Jakub (referee) ; Šilhavý, Pavel (advisor)
Goal of this work was to develop software to control noise injector DLS-5410DC and noise generator DLS-5800 and be able to perform automatized measurement of tranmission parameters of DSL line.The first part describes different noises on DSL line. In second part is described the software, how it was designed and developed. Software allows user to remote control devices, edit and apply noise profiles and perform automatized measurement of transfer characteristics. Software was programmed in C\# programming language on .NET Framework 4.0 platform. For programming was used Microsoft Visual Studio 2012.
|
|
|
VDSL2 vplus and G.fast technologies and their testing
Vehera, Vladyslav ; Číž, Radim (referee) ; Šilhavý, Pavel (advisor)
This semester work focuses on the basic characteristics of the VDSl2 and G.fast technologies that allow to transfer data using old telephone lines. The theoretical part of the work describes the main parameters of all currently known profiles for VDSL and G.fast. There is also a description of DMT modulation, used in both types of DSL connections. Moreover, the theoretical part presents a vectoring technique that helps to increase the data transfer rate using a twisted pair. The work also provides methods for testing networks using the recommendations of RFC 2455, ITU-T Y.1564 and RFC6349. The practical part of this thesis contains all conducted tests and measuring, which were described in detail. The results od these tests were presented in the format of graphs and tables.
|
guest ::
