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Simulation and evaluation of scenarios running real-time UMTS services in Opnet Modeler environment
Klimeš, Roman ; Molnár, Karol (referee) ; Novotný, Vít (advisor)
This work deals with the Universal Mobile Telecommunications System problems. It researches the parameters of influencing the UMTS Terrestrial Radio Access Network behaviour where is the Quality of Services support necessary. The aim of this master’s thesis is the simulation and evaluation of scenarios running real-time UMTS services in Opnet Modeler environment. In the first part is the short introduction to this technology problem. The requirements and the aims, the frequency plan, the network architecture and the Quality of Services support in UMTS are described. Creating the mobile network in the OPNET Modeler environment, configuration of the particular elements with the correct functionality and finally the parameters configuration for the Quality of Service at all workstations was the practical part of this work. At last phase was needed to compare the final statistics of the model without QoS support and the model with QoS support. I verified my knowledge in the OPNET Modeler program and the expected simulation results were confirmed. The final part of the thesis was creating the laboratory problem on the basis experience gained.
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QoS Implementation in Access Network
Adámek, David ; Molnár, Karol (referee) ; Filka, Miloslav (advisor)
This diploma thesis deals with computer networks which play a key role in present society. More and more demands are placed on these networks (especially on quality of services and throughput) because of fast-growing developement of services such as voice and video real-time transmissions. All the packets in typical Ethernet networks are equal. Therefore it is sometimes impossible for the application to maintain required throughput speed of a network. For this case it is useful to take some mechanisms into the consideration. These mechanisms (sometimes called QoS) are able to distinguish different types of transmissions and traffic, analyze them and then prioritize them according to some pre-defined set of rules. The most famous mechanisms are Integrated Services and Differentiated Services. The implementation of Differentiated Services is the goal of this thesis.
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Application of TCP in OPNET Modeler simulation environment
Tirinda, Viktor ; Kubánková, Anna (referee) ; Molnár, Karol (advisor)
This diploma thesis describes a possibility of application protocol implementation in OPNET Modeler simulation environment. It presumes that this application protocol is going to use TCP protocol for their communication on transport layer. The first part of thesis is focused on a description of TCP. It is a connection oriented, reliable and confirmed protocol which maintains sequence of transmitted data. This data is after receiving positively confirmed. In the second chapter are described the main functions of OPNET Modeler simulation environment. OPNET is hierarchical divided into four editors. Each editor has a specific function by creating a network and setting his behavior. There is also focused on the two lowest layers of OPNET Modeler and their components in detail, which are participating at usage TCP on transport layer to communication. Implemented applications communicate by sockets, which are created and destroyed on request. Communication is controlled by manager process, whose function is maintenance particular connections and redirect dataflow into relevant process. This manager put in action as well a process, which simulates a single TCP. In the practical part I made two applications: one is a client type and a second one is a server type. Both applications are using TCP on transport layer. The establishment of connection initiates a client, who is sending a request to the server for a data. Then server sends back data in desired quantity. After sending the entire data, client terminates the connection. The result of simulation is statistics, where we pictured the size of the transferred data, a number of transferred packets and other parameters typical for TCP.
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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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Advanced modelling of SNMP behaviour in OPNET Modeler simulation environment
Bezchleba, Josef ; Skořepa, Michal (referee) ; Molnár, Karol (advisor)
The aim of my diploma is to introduce the SNMP protocol designed for remote device management to the readers and present its implementation into the Opnet Modeler simulation environment. For the implementation the DiffServMIB database has been chosen, which describes the components of differentiated services mechanism. My diploma thesis describes in detail the possibilities of application of the DiffServMIB database in traffic management. The design of a simulation model, which represents the differentiated data processing in input and output direction on a router interface, is also introduced. Next, this model is implemented into the Opnet Modeler simulation environment. The goal of this simulation model is the possibility of simple configuration of individual MIB attributes. In my work I also suggest an implementation method able to interconnect the MIB database with the configuration process of the active network element - with focus on output procedures of DiffServ mechanism.
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Development trends of TCP for high-speed networks
Modlitba, Jan ; Molnár, Karol (referee) ; Vyoral, Josef (advisor)
The master's thesis solve the problem of setting new TCP variants for high-speed IP networks. The first goal was to describe in detail the behaviour of TCP and then analyse a problem of utilization the available bandwidth with standard TCP in high-speed network. Work consequently deals with selection and description the most perspective ones. Further the reader is familiarized with reasonable simulation tools of existing problems and their brief description. Main part of this thesis presents examination of performance of new TCP variants for high-speed network. During the examination the aspects on efficiency and fairness of competition flows on shared bottleneck are taken. The results are tabularly displayed plus compared with each other.
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Implementation of parametric models dependent on instantneous values of network traffic in OPNET Modeler simulation environment
Šibík, Štefan ; Hošek, Jiří (referee) ; Molnár, Karol (advisor)
The aim of this diploma thesis was to create an own DiffServ domain model, which is supplemented with stations generating various type of network traffic and implementation of token-bucket mechanism in router´s process model in Opnet Modeler simulation environment. DiffServ domain is made up from two edge and two core routers and includes servers and client stations generating VoIP, FTP, HTTP and database access traffic. It is described a process of distribution of traffic into different classes on edge routers of DiffServ domain along with assurance of separate handling with usage of an Assured Forwarding PHB mechanism. In point of differentiated packet processing is process model completed with generating of various statistics. The process of their creating is used to check a dropper activity, which is implemented together with token-bucket mechanism on ARP layer of the router. The functionality of the model is verified by simulation.
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IP Multimedia Subsystem and its usage for quality-of-services assurance
Betlach, Michal ; Molnár, Karol (referee) ; Hošek, Jiří (advisor)
The aim of this work is to give information about the structure and elements of the IP Multimedia Subsystem, using signaling protocol and transferring messages between the terminal and elements of IMS. Create model, which implements messages transfer between terminal and IMS elements, by environment tools OPNET Modeler. This work describes system function IMS, its architecture, basic elements, architecture of using signaling protocol SIP and its elements, SIP and SDP messages format and the way of ensuring Quality of Services. There is a project of model terminal registration and reservation data flow by terminal in the IMS. These models were realized in a simulation environment called OPNET Modeler by using tools: project editor, node editor and process editor. In the last part of this work, the method of verification correct function of realized models was created by simulation tools called Debbuger. This tool is one of the environment tools OPNET Modeler.
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Comparison of architectures of MIB system databases designed for QoS management in data networks
Jelínek, Tomáš ; Hošek, Jiří (referee) ; Molnár, Karol (advisor)
Bachelor thesis deals with Diffserv mechanism for Quality of Service in data network and goes through several parts of structure MIB database for managing Diffserv mechanism. The first chapter is introduction. I explain SNMP protocol in the second chapter. In the third chapter I deal with Quality of Service (QoS) and in the next chapter I explain Diffserv mechanism and its architecture. In fifth chapter I present possibilities of using Policy Information Base (PIB). I show several parts of MIB database in the sixth chapter. I compare two parts of MIB database and summary whole work in the last chapter.
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Mechanisms of QoS assurance in fixed, wireless and mobile data networks
Václavek, Radovan ; Novotný, Vít (referee) ; Molnár, Karol (advisor)
This bachelor´s thesis deals with mapping technologies and base parameters used to guarantee the quality of systems in the local area networks, including wireless and mobile ones. I have focused mainly on requests and classifications, which are typical for the types of networks on link layer. In Ethernet I focused on the gradual trends in the fore mentioned technologies and IEEE 802.1Q and connected IEEE 802.1p standards included. The next part describes the quality of systems in wireless nets in different types of environments and again uses given standards for quality of systems guarantee in 802.11e and connected 802.11a/b/g standards. The next part focuses on the latest generations of mobile nets, looking at the types and trends of the latest technologies. Here I draw from standard project 3GPP, which describes the problems with these technological developments. The next part focuses on WiMAX technologies. In the penultimate paragraph, the constituent network technologies are compared from the view of securing QoS and I propound possible ways of securing coversion of constituent technologies. The conclusion summarises all the technologies I have mentioned and the future trends including possible problems and challenges with these latest technologies.
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