National Repository of Grey Literature 6,117 records found  beginprevious6098 - 6107next  jump to record: Search took 0.33 seconds. 

Design and realization of client application for cooperation with ONET Modeler
Polak, Martin ; Jelínek, Mojmír (referee) ; Molnár, Karol (advisor)
The bachelor thesis „Design and realization of client application for cooperation with OPNET Modeler“ is about trying to bring a client to easier and better communication with the server. Open new opportunities for effective work in the network. Goal of this work is to interconnect two communication stations, which will together communivate. OPNET communicates with an external program which redirects the data to the network layer. The work describes the individual steps in creating a model client. Part of the work is introduction to the OPNET Modeler simulation environment, whereupon it is tied together a detailed desciption of programming of an external application.

Laboratories with CCENT Network Visualiser
Kadlčík, Michal ; Pelka, Tomáš (referee) ; Burda, Karel (advisor)
This work describes design and practical realization of three laboratory works for students of MNSB. These works are aimed to practice basics of computer networks, especially the configuration of LAN, IP addressing and routing. Local desktop simulator of computer networks CCENT Network Visualizer is used as a training program. Networks are created with the help of several graphical objects, which are configured and diagnosed as a part of this lab work. Additionally there is software that supports studying in the form of web pages, where the lab tasks are mentioned with correct results and some examples. Also the possibility of taking included tests and evaluation of answers. The simulator combined with the software is run by students on VMware virtual machine, so the work deals as well with the implementation on computer workstations.

UMTS network simulation in Opnet Modeler environment and real network operation
Kuchár, Peter ; Molnár, Karol (referee) ; Novotný, Vít (advisor)
This bachelor thesis is devoted to mobile networks and specially to UMTS. First part contains theoretical information about mobile networks, history and present of mobile communication. It continues with comparasion between Node-B specification in the Opnet Modeler 14.5 and real node by 3GPP international community. Second part describes works on simulation and results of measured parameters. Simulation is focused on sensitive services like a VoIP or video. In simulation voice service is used VoIP and few data services running in background. Measurement in real network was executed in several networks which belong to different providers and supports different techniques. In real networks IxChariot was used. IxChariot is the industry’s leading test tool to predict device and system performance under realistic load conditions. Real network results and results from Opnet Modeler 14.5 simulation are practically equal. Aplication of Hamachi in real network did not have influence on the results measured.

Evaluation of influence of UMTS radio access network parameters on network performance using Opnet Modeler simulation environment
Konečný, Zbyněk ; Škorpil, Vladislav (referee) ; Novotný, Vít (advisor)
This bachelor thesis deals with testing the effect of various parameters and their subsequent influence on the operation of the entire UMTS access network. Each simulation will be implemented in Opnet Modeler, which is used for network testing based on packet switching. The aim of this work is the most effective operation of UMTS networks. Since the UMTS network uses a shared radio environment for all users close to one transmitter, the total capacity of one cell is dependent on the size of interference produced by mobile terminals in the cell. Increasing the capacity of cells can be done by properly elected handover. The first part of this work will therefore concern different types of handovers and their impact on the network operation. Nowadays communication through mobile packet networks is becoming more and more important and that is why the second part of this work will focus on the simulation of traffic UMTS networks. It will be simulated by the behavior of individual applications without the use of QoS. Then the application will be assigned to different quality classes and the quality of service will be compared with simulations without using QoS. The conclusion of this work will contain laboratory work, which should partly make the students familiar with the data traffic in the UMTS network through a simulation program – Opnet Modeler.

Experimental network for QoS support testing
Fogl, Miroslav ; Mácha, Tomáš (referee) ; Novotný, Vít (advisor)
The work specifies problems with support of qualitative requirements in IP network services on the network and link layer. There are also described options of qualitative support of individual networking components in the UTKO laboratory (routers, L3 switches). Created experimental network is loaded by various types of service (VoIP, FTP, HTTP, Video). Data services realization is ensured by available terminals (IP phones, IP cameras, IP video-phones, servers, client stations). Metering is targeted on the manipulation with packets in the router. Options which Cisco router offers are verified by packet analysis. Available methods of dropping are compared on the base of metering and evaluated. Optimal handling with output queue after metering in experimental network is LLQ mechanism. It is able to prefer packets according to their priority in the IP header. Further the difference of link overloading by huge dataflow after QoS policy using is simulated. To reach availability of data services in the whole network is necessary to deal with mechanisms for qualitative services support in all the network components in the network.

Software based optical cable documentation
Martínek, Michal ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
The focus of this work is a description of search-optic cables and cables stored in the Earth's surface suitable method and the possibility of registration of the optical paths and components in the ArcGIS geographic information system. The work set out in detail the different types of optical fibers and principles listed in the wiring examples most commonly used cables. There are additional elements used in the construction of optical networks, whether the individual connectors, hubs, etc., as well as protection features most often used for distribution of optical cables. There are also examples given options stowages routes and laying cables, and most currently with the possibility to discover a practical listing and description of these search engines non-metallic elements. The work also focuses on how these elements efficiently record to go to them quickly and easily access and simplify their close location in real space, to ensure unwanted destructive interruption, or any repair, expansion, etc.

QoS implementation in access network
Hauser, Václav ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
My bachelor thesis deals with the implementation of quality of service in the access network. My bachelor thesis describes at first the concept of quality of service and its characteristics. In addition, it makes the reader familiar with various implementations models. At first with integrated services, which are based on the RSVP reservation protocol. The task of this protocol is to establish the route through the reserve RESV and PATH messages. The second implementation model contains the differentiated services. There is no reservation protocol, quality of service is ensured by using the classification of individual data flows. Accordingly, as packets are classified, they are assigned according to a priority, which is crucial for the packets travel through the network. Next part of this thesis describes the implementation of any different types of configuration of two implementation models of quality of services. There is configuration of RSVP protocol, MQC, AutoQos and MLS QoS. Final chapter describes the configurations examples.

QoS in a computer network of VŠE
Kalina, Tomáš ; Pavlíček, Luboš (advisor) ; Beneš, Jiří (referee)
The diploma thesis is focused on analysis and deployment of Quality of Services (QoS) in a computer network of The University of Economics in Prague (VŠE). The thesis describes the main QoS technologies focusing on technology Diffserv and its deployment with using available network devices in computer network of VŠE. In thesis the needs of network services and protocols for quality of services with division into different classes of services according to priority are discussed. The thesis explains the benefits and drawbacks of deploying QoS in the environment of VŠE with regard to wired and wireless network. In the practical part recommendations are applied to the production network and subsequently the benefits of modification are evaluated.

Principals, switching functions and routing techniques in computer networks
Dvořák, Pavel ; Pelka, Tomáš (referee) ; Polívka, Michal (advisor)
This bachelor thesis consider main principles and function of active network components. Mainly is intent to component working on the third level of referential model ISO/OSI, router. There are described its main parts and more closely charactered routing protocols. Then is verified the ability of dynamic routing to react to failure in the network and there is measured the reaction time of crossing to secondary route when using different routing protocols. Another part of the thesis is focused on the questions of Quality of Service (QoS) and its support in computer networks. There are explored various ways of the QoS configuration on the routers and the proper of them is chosen and applied to the test network.

Measurement of the fiber optical transport links
Ambrož, Jan ; Škorpil, Vladislav (referee) ; Reichert, Pavel (advisor)
This thesis deals with the measurement of optical transport links. In particular, the measurement of attenuation, chromatic and polarization mode dispersion. Specic me- asurement systems using a WDM and passive optical networks. Within each chapter are listed the causes and eects restrictive factors and methods of measurement. In chapter Attenuation measurements are described radiation and material loss as the main causes of depression. Methods whitch are described two lengths, insert loss and reectometri. Chromatic dispersion at dierent speeds of various wavelengths limits systems with high transfer rate. Methods of measuring the phase shift, dierential phase shift, pulse time delay and interference. Polarization mode dispersion is a random phenomenon caused double refraction, must be measured after completion of the route. Scanning wavelen- gth, traditional and general interference, reectometri and the polarimetric are methods of measurement. It described the measurement of WDM systems in three stages of its build. In brief PON networks are presented, with the specicities of the measurement over splitter. Most chapters are supplemented by the results and conclusions of practical measurements. At the end of the work are given by the two standards deal with the measurement of optical transport links.