|
|
Communications Technology Internet Of Things
In Cisco Packet Tracer
Beneš, Pavel
This work is aimed at simulating the Internet of Things in Packet Tracer. In this work, a network containing IoT devices is created in the Packet Tracer simulation program. In the network, the parameters affecting the quality of the network are subsequently monitored, depending on the number of connected devices, and these measured values are subsequently evaluated.
|
|
|
Optimization of data transit in network
Řezáč, Michal ; Škorpil, Vladislav (referee) ; Kubánková, Anna (advisor)
This bachelor thesis is divided into two parts. The first part deals with and describes necessary teorethical units, together with analyse of ISP network and other input informations. These findings are further used in second part of bachelor thesis. The practical part dealt with testing of optimization mechanisms in the laboratory network. Thereafter has been done a wider tests of optimization mechanisms based on different ways of marking data streams and deploying these rules. The advantages and comparision of these methods were further evaluated.
|
|
|
Verification of stable next generation networks via transmission parameters measurement
Gregor, Lukáš ; Čučka, Milan (referee) ; Grenar, David (advisor)
This thesis deals with the measurement of transmission parameters in the new generation access networks NGA. The aim of the thesis is to build and configure a test network and scenarios for the measurement of service quality parameters and then verify the transmission stability. The theoretical part describes general functioning of NGN networks, the requirements of different telecommunications services on quality parameters, methodology and recommendations for measuring transmission parameters in packet networks. The practical part deals with the configuration of scenarios using mainly MPLS technology and methodology of their testing. Measurements were performed according to recommendations IETF RFC 2544, IETF RFC 6349 with the ExacTCP test and ITU-T Y.1564 with the EtherSAM test. For measurements were used measuring instruments of EXFO brand. In conclusion, the measurement results according to the mentioned standards were evaluated and also the advantages of using the measurement according to the given standard in NGA access networks were discussed.
|
|
|
Implementation of HDLC protocol in network simulators
Polášek, Jaromír ; Mašek, Pavel (referee) ; Pokorný, Jiří (advisor)
This diploma thesis deals with the possibility of using HDLC (High-Level Data Link Control) protocol for communication and addressing of smart metering devices with a data concentrator. The HDLC protocol is used in two DLMS/COSEM (Device Language Message Specification/Companion Specification for Energy Metering) communication profiles. To simulate these communication profiles, the most appropriate simulation program is selected. Using this simulator, the first communication profile is implemented and the second one is designed. Communication profile based on TCP/IP (Transmission Control Protocol/Internet Protocol) has been fully implemented. To implement the three-layer HDLC communication profile, all options have been thoroughly explored. Using these findings, a process was designed to guide the full implementation. For the first communication profile the qualitative parameters are measured, which are then plotted and evaluated.
|
|
|
Laboratory of Quality of Service
Eltahir Ahmadon, Ahmed ; Kolka, Zdeněk (referee) ; Polívka, Michal (advisor)
The Bachelor's work, you are reading, deals with the issue of VoIP calling and measurement its quality. In the following paragraphs the discussion will be about the basics of networking protocols such as TCP, UPD, IP and SIP, after that a preliminary introduction to QoS issues - ways of measuring voice quality for instance MOS and E-Model. Importance of implementing QoS for VoIP, and QoS parameters used in the proposed services (will be called "mechanisms"), such as Best effort service, Integrated and Differentiated services. Based on these fundamentals points with designed laboratory for quality of service. The laboratory will be aimed at testing the quality of codecs with regard to bandwidth, jitter, delay and packet loss. The solution lies in the fact that, which codecs are actually suitable for the service.
|
|
|
A system for monitoring the quality of connectivity
Vyskočil, Vladimír ; Peterka, Jiří (advisor) ; Děcký, Martin (referee)
The aim of the theses is to design a methodology for centralized monitoring of data traffic in an ISP network that would detect individual connection with connectivity problems, and evaluate these problems. The methodology should at least evaluate packet loss and latency between a centrally located monitoring point and endpoints at user premises. A further goal is to implement this methodology, test it and evaluate the results.
|
|
|
Measurement of transfer speeds and delays in computer networks
Bárdossy, Adrián ; Kubánková, Anna (referee) ; Jeřábek, Jan (advisor)
Bachelor thesis is interested in measurement of transfer rate and latency in computer networks. In the first part of thesis is defined, which motodics of measurement we know, various RFC and their specifications, also various parameters about measurement in computer networks like bit rate, capacity of channel, latency. In the second part are prepared users interfaces and softwares for applying the measurement of thesd parameters. In the last part is application of these softwares and creating and testing methodic of network measurement.
|
|
|
Measurement of influence of network impairments on VoIP call quality
Zelenay, Martin ; Krkoš, Radko (referee) ; Šilhavý, Pavel (advisor)
This work explores, analyzes and rates influence of network impairments on VoIP traffic. It describes how voice over IP is carried according to standards. There are described concepts and basics of VoIP networks with orientation on facts necessary to understand analyzed actions and measurements in theoretical part. In practical part, there is described realization of tests according to instructions with orientation on initial checking of devices and rating models and then measurement of influence of network impairments on quality of calls with use of these devices and Opensource PBX Asterisk.
|
|
|
Laboratory of Quality of Service
Eltahir Ahmadon, Ahmed ; Kolka, Zdeněk (referee) ; Polívka, Michal (advisor)
Abstrakt Bakalářská práce se zabývá problematiku IP telefonie, emulace sítě a kvalitou službou (QoS). Kapitol 2 pojednává o model TCP/IP a OSI, síťových protokolech (IP, TCP, UDP) a o protokolu SIP. Kapitole 3 se zabývá problematikou QoS, definicí QoS, QoS ve službách s reálným časem, parametry a způsoby změření kvality hlasu – subjektivními a objektivními testy. Na základě získaných poznatků byla navržena laboratoř kvality služby. Laboratoř je zaměřena na testování kodeků z hlediska kvality přenášeného zvuku, s ohledem na šířku pásma a ztrátovost paketů. Laboratoř kvality služby byla navržena tak, aby byly splněny požadavky na subjektivní testy uvedené v kapitole 3. 4. Návrh laboratoře Schéma navržené laboratoř je zachyceno na obr. 4.1. Návrh je složen ze čtyř hlavních částí – Dvou softwarových IP telefonů (XLite), síťového emulátoru (WANem Wide Area Network emulator), a SIP ústředny (3CX Phone System pro Windows od 3CX Ltd). Sestavování spojení prbíhá podle stejného schématu viz obr. 4.1. Oba koncové uzly jsou připojeny přes emulátor WANem. Počítač, na kterém je emulátor instalován má dvě síťová rozhraní. PC1, resp. PC2 s WANem tvoří lokální síť 1 (LAN1), resp. lokální síť 2 (LAN2). Pakety prochází z jednoho uzlu do druhého přes WANem. WANem emuluje chování skutečné WAN sítě, umožňuje provádět v laboratorním prostředí testy na síti s přesně definovanými parametry. Návrh celé laboratoře je virtualizován. Je využita platform VirtualBox od Oracle. Podrobně je návrh popsán v kapitolách 4.1 a 4.2. QoS měření Během měření byly dva parametry sítě proměnné, resp. přesně určené nastavením WANemu – šířka pásma a ztrátovost. Protože testování probíhalo v místnosti, ve které se nachází elektronická zařízení a jiné zdroje ruchů, byla metoda ACR daná doporučením ITU-T P.800 upravena viz kapitola 4.3.1 Testovanému subjektu byly testovací nahrávky přehrávány do sluchátek. Dle ITU-T Rec. P.800 doporučuje několik metod hodnocení kvality služby – MOSLQ, MOSLE, MOSLP, ACR a CCR. K praktickému ověření funkčnosti navržené laboratoře byla vybrána modifikována verze ACR (M-ACR). Použité náhravky obsahují tři věty, mezi něž jsou vloženy mezery (volný interval – bez zvuku). Výsledky subjektivních testů jsou shrnuty v tab. 4-1 až tab. 4-10. MOS byl vypočítán pomocí rovnice (3. 1), jehož výsledky shrnuty v tab. 4. 11. Závěr Navrhovaná laboratoř byla úspěšně otestována, návrh splnil očekávání. S využitím navržené laboratoře proběhly subjektivní testy kodeku G.711 na 10 osobách.
|
|
|
Open-Source Software Tools for Network Diagnostics
Loffay, Pavol ; Ráb, Jaroslav (referee) ; Matoušek, Petr (advisor)
The aim of this work is to make a research of existing open source tools, which are concerned with the diagnosis of the network transmission in the form of measuring of throughput and other basic parameters. The work is devoted to the construction of methodics for testing and comparing devices between themselves. The result of the work is recommendation to an ordinary customer the right application for measuring of given network transmission parameter.
|
guest ::
