|
|
VoIP Quality Analyzer
Havelka, Ondřej ; Žádník, Martin (referee) ; Tobola, Jiří (advisor)
This master thesis deals with the design and implementation of an application for analyzing Voice over IP quality using NetFlow. In the beginning, there is summarized basic information about VoIP technology and NetFlow - its principles, the most used protocols, factors that have influence on call quality and call quality rating methods. Later there is presented proposal of application and then described its implementation. The created application was tested on samples, which simulate calls in network with delays and packet-loss. Within testing was made the comparison with commercial application and the results are discussed.
|
|
|
Evaluating the effectiveness of complex protection measures in cadastral area Jerlochovice in Husí potok Watershed
Matoušek, Petr ; Sobotková, Veronika (referee) ; Dumbrovský, Miroslav (advisor)
A subject of this Thesis is the design of the complex system of measures of soil conservation in given catchment area, which will serve as a concept of complex land consolidation in cadaster Jerlochovice. Based on the analysis and the land survey, a feasible solution was designed using the hydrological and erosive tools of ArcGIS. For the identification of areas endangered by erosion and for the identification of runoff conditions, the Universal Soil Loss Equation of Wischmeier-Smith was used (in grid modification). Based on the calculated values, the suitable technical and agrotechnical measures of soil erosion control were designed. Each component was designed for the values of Qn from the model DesQ. Subsequently the efectivity of the designed measures was evaluated by the comparison of results of erosive and runoff conditions before and after the aplication of the soil and water conservation measures.
|
|
| |
|
|
VoIP Quality Analyzer
Krajíček, Michal ; Žádník, Martin (referee) ; Tobola, Jiří (advisor)
This thesis deals with the quality of the IP telephony and its measuring using the netflow technology. It describes individual factors influencing the quality from sampling and quantization over the impairment caused by codecs to the degradation during network transfers. Next part focuses on models allowing to regard quality of IP telephony with emphasis to the E-model and R-factor. It shortly describes the netflow technology and the quality measuring connected with it. Practical part describes the principle of how the quality is measured by the netflow probe nProbe together with offer and implementation of application measuring the quality. The comparison with commercial application is presented and the results are discussed.
|
|
|
Quality Analysis of VoIP Calls
Basel, Martin ; Ryšavý, Ondřej (referee) ; Matoušek, Petr (advisor)
This bachelor's thesis focuses on methods for evaluating quality of VoIP calls. You can read about analysis of RTP/RTCP packets and use this knowledge for computing statistics required for assessing quality of VoIP calls. Also, I explain the method, which is implemented in plugins that work in FlowMon probe. Finally, you will see the results compared to the other programs.
|
|
|
Measuring Quality of Telephone Calls with the Asterisk PBX
Bílek, Petr ; Šilhavý, Pavel (referee) ; Daněček, Vít (advisor)
This thesis contains description of the present methods and algoritms for measuring the quality of telephone call on the PBX Asterisk. Further develop the concept of a system for measuring and implementing the call embbeded system VOIPAC PXA270M. Based on theoretical analysis is carried out discussions between C, Java and PHP,which results in the selection of appropriate programming language suitable for implementation in embedded system. The concept is realized by creating an application written in a particular programming language. Part of this work is verification created application using experimental measurments of telecommunications system. The results of experimental measurements are discussed in the final evaluation.
|
|
|
Analysis of the dependence of communications services to the delay and QoS optimization
Schön, Martin ; Číka, Petr (referee) ; Hošek, Jiří (advisor)
This thesis discusses wireless network standards 802.11a/b/g/n. First part explains basic principles of networks and media access. Next the standard IEEE 802.11, general QoS parameters and their application in wireless networks, according to standard 802.11e are analyzed. Second part of the thesis verifies the acquired knowledge in simulating program Opnet - effects of the delay, jitter and packet loss on VoIP call are tested. In the last part of the thesis a network for video streaming has been designed. The video was streamed in different qualities and the influence of other network traffic (with and without the support of QoS) on the video streaming was tested.
|
|
|
Testing of voice quality of VoLTE/VoWiFi technology
Kráčala, Martin ; CZ, Radek Penížek, T-Mobile (referee) ; Hanus, Stanislav (advisor)
This master’s thesis deals with application of the ITU-T G.107 E-model for objective non-intrusive voice transmission quality measurements in LTE and Wi-Fi networks. The first part presents techniques used for voice quality measurements, particularly algorithm POLQA, analysis of the E-model and overview of the VoLTE and VoWiFi technologies. The main part of this paper consists of design of the R-factor calculation formula using parameters measured by Android OS powered devices. The algorithm design is based on extensive VoLTE measurements and its voice quality prediction successfulness is evaluated by comparison with POLQA measurements. The paper also presents implementation possibilities of the proposed algorithm on devices with Android OS.
|
|
|
Testing of voice quality of VoLTE/VoWiFi technology
Kráčala, Martin ; CZ, Radek Penížek, T-Mobile (referee) ; Hanus, Stanislav (advisor)
This master’s thesis deals with application of the ITU-T G.107 E-model for objective non-intrusive voice transmission quality measurements in LTE and Wi-Fi networks. The first part presents techniques used for voice quality measurements, particularly algorithm POLQA, analysis of the E-model and overview of the VoLTE and VoWiFi technologies. The main part of this paper consists of design of the R-factor calculation formula using parameters measured by Android OS powered devices. The algorithm design is based on extensive VoLTE measurements and its voice quality prediction successfulness is evaluated by comparison with POLQA measurements. The paper also presents implementation possibilities of the proposed algorithm on devices with Android OS.
|
|
|
VoIP Quality Analyzer
Krajíček, Michal ; Žádník, Martin (referee) ; Tobola, Jiří (advisor)
This thesis deals with the quality of the IP telephony and its measuring using the netflow technology. It describes individual factors influencing the quality from sampling and quantization over the impairment caused by codecs to the degradation during network transfers. Next part focuses on models allowing to regard quality of IP telephony with emphasis to the E-model and R-factor. It shortly describes the netflow technology and the quality measuring connected with it. Practical part describes the principle of how the quality is measured by the netflow probe nProbe together with offer and implementation of application measuring the quality. The comparison with commercial application is presented and the results are discussed.
|
guest ::
