The topic of this diploma thesis has been chosen for a discussion and implementation of quality of service on the application and link layer of the OSI model. At the beginning of this thesis the general parameters and basic technologies of the OSI model network layer has been explained. This part was chosen as a resource for explanation of the basic parameters in the quality of services. Basic part is followed by the introduction to the Ethernet technology, which became as a ground for the real model in this diploma thesis. As a part of this section has been written a block which contains a analysis of quality of services in the Ethernet, which means the implementation of IEEE 802.1Q/p. This analysis is followed by structured descrition of the controlling and functionality of quality of services parameters on the link layer with the system tool in the Windows XP, description of Win XP link layer drivers and its modification with system tool tcmon. The end of the theoretical part is represented by introduction to the implementation of quality of service in the wireless networks especially the 802.11e standard. At the beginning of the practical part is specified the description of the topology design which is dedicated to the quality of services implementation. This section is developed to well-founded analysis of applications which were used during topology creating. The last segment of this thesis is dedicated to evolving the practical informations which were obtained during the measurement.

The main aim of my master thesis was to get acquainted with the implementation of quality-of-service support methods in UMTS 3G mobile network and the evaluation of these methods in a simulation environment with main interest in the characteristic features of the traffic classes. The impact of the QoS methods available on different service types were verified in the OPNET Modeler simulation environment. I examined mainly the potentials of the model to support the required quality parameters for the connections. The models of typical network applications, available in real UMTS networks, together with two examples of mobile networks, operating voice and video services in combination with standard data services, were defined in this simulation environment. My work also contains the detailed description of configuration parameters fundamental for correct behavior of the simulation models. The simulation also shows the case, when the transport service is rejected due to the lack of network resources. The key parameters of the model are also described and their effect on the service quality with and without QoS control are compared in separate scenarios. Finally, I investigated the effect of mobility of the end stations on the communication process, especially on the duration of a file transmission.

The Master’s thesis ”The Implementation of the Advanced Filtering Based on the Packets’ Classification using Linux” is intended to the realization of an internet gateway. The gateway serves to make the connection between local network and the internet. The thesis contains a short theoretic description of parameters and types of QoS services. The classful and classless queues are mentioned in detail. The last theoretic part refers to the introducing of LDAP protocol and its usage. The practical part of this thesis captures the configuration of firewall, dns and radius server connected with LDAP databases. The thesis also contains detailed description of the production QoS by HTB with L7-filter including the compilation of system’s core. The end of the thesis contains the series of tests of created scripts.

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.

The diploma thesis addresses facility of QoS control with GNU/Linux tools iptables and iproute. An attention is focused especially on HTB and HFSC traffic shaping methods with regard to utilization in wireless networks. The paper also includes a simulation of ensuring QoS in wireless network with 802.11e amendment.

In this work an interface between network simulator OPNET Modeler and network operations generator IxChariot is described. The goal is to control the generator by data from an OPNET modeler simulation. More accurately the generator is supposed to produce a data flow with desired settings of DSCP field, which is used to support quality of service mechanism. The goal can be achieved by two possible approaches: using IxChariot TCL API or IxChariot C API. Both of these approaches are described and conclusions are made at the end.

The master thesis „IP traffic performance“ is focused on traffic testing in IP networks. Theoretical section explains routing issue in an autonomous system. This work contains a detailed description of OSPF protocol. This work also deals with behavior of a link failure. There are described mechanisms that are used to link failure detection and subsequent traffic rerouting. The next section describes mechanisms to ensure quality of service. In master thesis are explained InterServ and DiffServ mechanisms. A large part is devoted to DiffServ mechanism that ensures distinction of data flows and classification packets into different classes. The routers than can process the individual data streams with different priorities. The practical section includes the design of experimental network and creation of simulation in Opnet Modeler. By using several scenarios are compared the characteristics of routing protocols and impact of QoS on the transmission characteristics of the network. Part of practical section is the improvement of OSPF protocol by adding a new metric and implementing a new metric in software suite Quagga.

In the introduction of this thesis the reasons for transition from older to a new technology called MultiProtocol Label Switching are mentioned – the modern technology enables simple network extension. The theoretical part contains basic principles of this techno- logy and their practical application for supplying private networks to the customers using provider’s network. In practical part packets are analyzed considering the theory. In addi- tion. All the technologies tested on a real network. Experience gained while working on this thesis are assessed during creating laboratory task for class Architecture of Networks intended for students of Bachelor’s study programme.

This thesis deals with the quality of service (QoS) mechanism in Evolved Packet System (EPS). The basic architecture and characteristics of the EPS are introduced. The concept of QoS is defined. Furthermore, QoS related entities, their functions and corresponding procedures are described. The methodology for measuring and evaluating of end-to-end QoS as seen from a user’s point of view is designed. This methodology is used to measure QoS of experimental cellular network at UTKO FEEC BUT. Finally, configuration change for optimizing the QoS support of experimental cellular network is designed.

This diploma thesis deals with OMNeT++, a simulation tool for network traffic simulations. It describes its installation, basic functions and its use together with an extension INET framework. Further it shows construction of a simple simulation, its parts and analysis of the traffic output. Briefly it explains Quality of Service, which is further practically implemented in visual simulations. The paper further contains two laboratory exercises with model protocols.