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QoS optimization and modern communication services delay analysis
Novák, Přemek ; Škorpil, Vladislav (referee) ; Endrle, Pavel (advisor)
This thesis consists of theoretical and practical parts. The theoretical part contains an analysis of the problems of wireless networkssolutions individual standards and methodologies to ensure quality of service. In the practical part using the OPNET Modeler, a number of different simulation models and their evaluation. It is a model of individual standards, support mobility and interference effects on quality of service.
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Modelling the wireless transmission channel in OPNET Modeler simulation environment
Spiglazova, Světlana ; Koutný, Martin (referee) ; Hošek, Jiří (advisor)
This diploma thesis deals with modeling wireless transmission in simulation environment OPNET Modeler. In theoretical part, there is described the very substance of spreading the signal via electromagnetic wave including impact of the surroundings that affects the spreading. These impacts have an influence on described selected parameters of wireless transmission of the signal characterizing its quality. Furthermore, there is described the OPNET Modeler setting, which allows designing the wireless transmission and by means of simulation verifies its functionality and acquires it is parameters. The transmission of the signal from transmitter to receiver itself is divided to individual steps, which are described in detail considering the implementation in aforementioned environment. In practical part, there is configured the basic model of wireless network and also executed series of simulations with different variants of commonly adjustable basic parameters of the transmission, as signal modulation, antenna types and network topology. Additionally, attention is turned to the stages of transmission itself, philosophy of their cooperation based on sharing the information via data units called TDA and their implementation in source code of the C++ language called transmission models. Based on these foundations is beyond beforehand defined created new user TDA and by means of simulation verified its correct implementation within packet switching. Values of the selected including user TDA are written in the window of simulation console with the help of the C++ language. Acquired results of the simulations are analyzed and documented in the conclusion. Source codes are available in the diploma thesis appendix.
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Analysis of MANET Routing Protocols OLSR and AODV in OPNET Modeler Simulation Environment
Machata, Tomáš ; Růčka, Lukáš (referee) ; Hošek, Jiří (advisor)
The thesis deals with MANET networks and it focuses on the routing process. Most attention is paid to the routing protocols AODV and OLSR. These protocols are described in the detail. The aim of the thesis is to create a simulation model of MANET network in OPNET Modeler environment. In this model the AODV protocol is configured. In order to achieve improved characteristics of the network traffic the routing protocol parameters are optimized. Furthermore the process model of AODV protocol in this environment is studied and extended by a new type of message, which allows a transfer of current transmission speed of MANET station network interface. Current transmission rate of stations is retrieved from the statistics. Every station periodically sends a message to neighboring nodes. The node stores the information into the file when a new message arrives.
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Modelling of advanced 802.11e technology features in OPNET Modeler environment
Šeliga, Michal ; Reichert, Pavel (referee) ; Molnár, Karol (advisor)
This master thesis includes a short review of the structure of WLAN (Wireless Local Area Network) technologies 802.11a/b/g, the description of their physical interface and the description of the basic medium access control mechanisms implementing the PCF (Point Coordination Function) and DCF (Distributed Coordination Function) methods. I mainly focused on the detailed evaluation the new 802.11e standard which was designed to efficiently support real-time services in wireless environment. To provide QoS (Quality of Service) support, this standard specifies the EDCA (Ehanced Distributed Channel Access) and HCF (Hybrid Coordination Function) medium access control methods for the shared wireless environment. The next chapter of my work is devoted to the verification of the theoretical results in OPNET Modeler simulation environment. I studied in details the WLAN model available in OPNET Modeler, the effect of data-flow classification into separate categories and the configuration of several access method parameters. Next, I created my own WLAN model according to the 802.11e standard. This model contains four applications two of them with real-time requirements. The model is divided into several scenarios, each focusing on different aspects of wireless network technologies like QoS support and it´s dependency on the number of clients, mobility of wireless terminals and comparison of the 802.11a/b/g and the 802.11e technology.
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IPTV multicast model with RTP protocol
Ležák, Aleš ; Skořepa, Michal (referee) ; Šimek, Milan (advisor)
This diploma thesis contains questions of simulation data transfer by ASM multicast. In simulation tool Opnet Modeler is proceed design of service IPTV. IPTV means television which is transfered in network by IP protocol. Data of IPTV service are sending by multicast transfer. Multicast is a technology which uses a group transfer. It is actually communication of a one source of data with many users. These users are receiving the same data. A main target of this technology is to decrement loading of source node and transference system in distribution of data towards group of users. Most often is multicast used in distribution of audiovisual data. Relation RTP/RTCP is simulated with a different numbers of users. Observed is interval of transmission of control RTCP packets. This will be reached by two methods which will be confront in the end. One is a theoretic calculation by course of a equation and second is a practical simulation in Opnet Modeler.
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Verification of MANET Routing Protocol potentials in OPNET Modeler environment
Konečný, Daniel ; Skořepa, Michal (referee) ; Hošek, Jiří (advisor)
This bachelor’s thesis called "Verification of MANET routing protocol potentials in OPNET modeler enviroment" is focused on MANET network. The first part is introducing routing protocols that are most used in OM. The second part of that work is strictly aimed to DSR routing protocol, its parametrs and configuration in OM. There is also discribed DSR process model. The most important part of that thesis is extension of data unit of DSR protocol and use that unit for transmision of information that are stored inside of its structure. As the extended unit was chosen Route Request packet that include new variable. The simulations are proving succesfull traffic of extension packet between nods with ability to store/read from RREQ extended structure.
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UMTS radio access network optimization in Opnet Modeler environment
Toman, Petr ; Herman, Ivo (referee) ; Novotný, Vít (advisor)
The differences between networks of mobile operators can be in their achitecture or the optimization of each network. The architecture is standardized which means there will only be differences in the willingness of mobile operators to invest in newer network elements. Network optimization is more important. The way of optimization isn't strictly given and depends on how the operator deals with it. The most important attribute in optimization is balance. The operators try to achieve balance among three important parameters. Those are capacity, coverage and maintaining QoS. Optimization depends on RRM algorithms. The algorithms include various functions such as admission control, congestion control, handover control, power control, etc. These elements don’t only affect the optimization but also affect each other, because they cooperate with each other. For example, an incorrect admission control of the network leads either to frequent network congestion because of a large number of participants in the network (participants are dissatisfied with the services offered by the operator) or to low utilization of the network because of too few participants in the network (the operator is dissatisfied because he is losing the possible earnings). Neither of these posibilities is good for the mobile operator, therefore it is important that the admission control is well balanced.
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Implementation of a simulation model for a simplified DiffServ-MIB database
Zeman, Otto ; Hošek, Jiří (referee) ; Molnár, Karol (advisor)
The aim of this work is to propose feasible solution for the simulation of the SNMP (Simple Network Management Protocol) protocol in the OPNET Modeler simulation environment. This work describes in detail individual procedures, which were chosen for this simulation . The work also contains an introduction to the OPNET Modeler simulation environment, the SNMP protocol, the DiffServ model and the DiffServ-MIB database. The main part of this work describes the algorithms programmed to model the functions of the SNMP protocol. Source codes of the algorithms programmed are included as well. The work deals especially with the functions for obtaining values from different levels of a multilevel model attributes, packet creation functions with dynamically changing length of user-data field, for the implementation process of a simplified DiffServ MIB database and with the functions for statistic creation.
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OLSR routing protocol for MANET networks in OPNET Modeler simulation environment
Hošek, Petr ; Molnár, Karol (referee) ; Růčka, Lukáš (advisor)
The first part focuses on general routing of computer networks. It describes the importance of routing, basic elements, algorithms and protocols. It also describes the so-called MANET networks, where there are discussed routing protocols in these networks. The next chapter deals with the analysis of routing protocols OSPF version 3 and OLSR protocol. For both protocols basic algorithms, their use and structure are described. In OSPF protocol there is also described historical development and differences between versions 2 and 3. The OLSR protocol properly describes the principle of MPR nodes, which is one of the most important parts of the protocol which differs it from the others. Next there is a brief introduction of a powerful simulation tool OPNET Modeler which allows simulating the operation and behavior of almost any computer network with a very extensive possibility of options for the functioning of the entire network, as well as nodes it selves. The practical part is divided into five parts. The first section describes the structure of process models, the basic elements, variables, and block editors OSLR routing protocol in OPNET Modeler program. The second part is devoted to the ICI data structure, which is used for inter-process communication and verify the creation and reception of messages using this function. The third part deals with the process model of OLSR routing model. There is a description of various blocks and functions involved in its function of protocol and significance. The fourth chapter shows an extension of data unit protocol OLSR HELLO messages to other fields, which is able to transmit a numeric value between neighboring stations, and these values print it in the console. The last block of the practical part is dedicated to creating its own message which is broadcast between stations like part of the OLSR packet messages. This message includes the parameter of actual data traffic rate of each communicating stations. These values are for each station exported to an external file for later processing.
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OSPFv3 dynamic routing protocol for MANET networks in OPNET Modeler simulation environment
Henzely, Július ; Skořepa, Michal (referee) ; Růčka, Lukáš (advisor)
This bachelor's thesis includes theoretical knowledge about fundamental informations related to functionality of mobile networks, with focus on MANET routing protocols. The project contains an overview of routing protocols, especially OSPFv3 routing protocol. In the practical section of project, there is a brief description of OPNET Modeler simulation environment and the process of establishing the network with configured routing protocol in it. The project also describes a procedure for extending of the Hello packet structure by a field containing node traffic speed in OPNET Modeler.
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