The thesis deals with simulation of routing protocols. The aim is to create a functioning model of OSPF link-state protocol in the simulation framework OMNET++. OMNET++ is a discrete simulation environment which was created to provide means to build models of various network protocols and technologies. Chapters in the first part of the thesis focuson the theoretical foundation of OSPFv2 and OSPFv3 and their differences. Important data structures, finite state automata and communication techniques are described and the information is later used to implement the model itself. The chapters in the second part deal with the implementation of the model in C++. The created model reflects the functionality of OSPF on Cisco devices.

WirelessSensor Networks have emerged among the different wireless technologies sharingthe ISM spectrum band. This band sharing between the technologies started toraise coexistence issues in accessing the overpopulated spectrum. The WSN powerconstrains make them vulnerable to higher power devices, such as WLAN.Simulation studies are of great importance in predicting the coexistencephenomena in heterogeneous scenarios. Simulations allows us to have aprediction on how a network will behave without the need to physically deploy thenetwork. We address the coexistence phenomena between WSN and WLAN devices and demonstratea performance comparison. We evaluate the capability of the MiXiM simulator to predictthe coexistence issues in heterogeneous networks, raised by WLAN and WSNdevices. We state the importance of having an accurate simulator to predict thephenomena. In this work, we propose a new framework for MiXiM to allow morerealistic simulation results in heterogeneous networks, when evaluating theinterference phenomena between concurrent technologies. We implement a newdefinition of custom transmission power and custom reception filter. Further,we evaluate simulation results provided by MiXiM in simulating WSN homogeneous scenariosand compare its prediction with analytical models. We implement a newsimulation paradigm in MiXiM, cross networks simulation sharing the same ISMspectrum band. We evaluate and analyse the coexistence phenomena of WLAN andWSN devices. Finally, we complete our work with the implementation of a channelsensing module, based on a fixed a priori false alarm probability, for WSNdevices. We evaluate its sensing results by comparing it with MiXiMsimplementation for channel sensing and conclude that our simple analytic modelfor sensing comply with MiXiMs implementation.

<p>Real-time networks are traditionally built on proprietary standards, resulting in a interoperability issues between different real-time netork implementations and traditional data networks mainly used in back office operations.</p><p>Continuity and supplier independence are a cause of concern with current</p><p>proprietary real-time networks.</p><p>This project evaluates the capability of providing real-time traffic over</p><p>switched Ethernet with EDF scheduling algorithm implemented at both the</p><p>switch and the node. By using OMNET simulation tool at packet level, it</p><p>is shown that the EDF implementation in switched Ethernet can guarantee</p><p>real-time traffic over the network and at the same time supporting non real-time traffic.</p>

IEEE 802.15.4 is a standard defined for wireless sensor network applications with limited power and relaxed throughput needs. The devices transmit data during two periods: Contention Access Period (CAP) by accessing the channel using CSMA/CA and Contention Free Period (CFP), which consists of Guaranteed Time Slots (GTS) allocated to individual devices by the network coordinator. The GTS is used by devices for cyclic data transmission and the coordinator can allocate GTS to a maximum of only seven devices. In this work, we have proposed two algorithms for an efficient GTS allocation. The first algorithm is focused on improving the bandwidth utilization of devices, while the second algorithm uses traffic arrival information of devices to allow sharing of GTS slots between more than seven devices. The proposed schemes were tested through simulations and the results show that the new GTS allocation schemes perform better than the original IEEE 802.15.4 standard.

Real-time networks are traditionally built on proprietary standards, resulting in a interoperability issues between different real-time netork implementations and traditional data networks mainly used in back office operations. Continuity and supplier independence are a cause of concern with current proprietary real-time networks. This project evaluates the capability of providing real-time traffic over switched Ethernet with EDF scheduling algorithm implemented at both the switch and the node. By using OMNET simulation tool at packet level, it is shown that the EDF implementation in switched Ethernet can guarantee real-time traffic over the network and at the same time supporting non real-time traffic.

North-East Pacific Undersea Network Experiments (NEPTUNE) is a multi-node cabled ocean observatory linked by 818 kilometers of powered fiber optic cable off-shore from Vancouver Island across the northern Juan de Fuca tectonic plate. It includes a Data Management and Archive Station (DMAS) at the University of Victoria (UVic) and a shore station at Port Alberni, BC, Canada. The core of the network consists of 6 branching units, 6 node stations, 13 junction boxes and more than 130 instruments. In this paper, we explore the costs and benefits of constructing a simulator for NEPTUNE using the OMNeT++ simulation platform---a C++ based discrete-event simulator. In this context, we present the design and implementation of a simple simulator that can work with a variety of configurations of instruments, where the instruments are connected to DMAS via junction boxes and branching units, and generate TCP and UDP traffic following certain patterns. The simulator is designed for supporting \emph{what-if} scenario analysis, particularly with respect to system evaluation and discovery of limits associated with network traffic behaviors. Our study reveals that, although building the simulator in OMNeT++ has many advantages such as ease of tuning and calibration, capturing sufficient details regarding the working behavior of the actual NEPTUNE environment is still challenging. A survey of alternative tools, including NS-2/NS-3, OPNET, JiST/SWANS, J-Sim, SSFNet, and Qualnet reveals that these nuances would not be any less challenging within these simulation environments. / Graduate

The aim of this Thesis is giving information about the network simulating system OMNeT++ and its extension INET framework and explore possible solution to implement missing protocol RIP. OMNeT++ is a discrete-event simulation environment. Source code is available and free for teaching and research purposes. Its primary application area is the simulation of communication networks, but because of its generic and flexible architecture, is successfully used in other areas like the simulation of complex IT systems, queueing networks or hardware architectures as well. The first part of Thesis decribes RIP protocol operations and conception of OMNeT++. At the second part of Thesis the implementation design and discussion of created modules and component is presented here. The final part of the Thesis was creating the laboratory problem on the basis experience gained. Implementation is realized in C++ programming language.

The Master's Thesis presents a theoretical introduction, familiarization with the issue and a implementation for a solution of a "network parameter validation" tool, which is founded on principle of network traffic monitoring. Firstly, the current development of computer network setup is analyzed with its limitations. This is an initial point for an introduction of a new approach for implementation and verification of required network setting, which uses techniques of verification, simulation and validation. After the introduction into the context, validation techniques are specifically examined. The Thesis main contribution lies in the capacity to determine appropriate parameters, which can be used for validation and also for implementation of the tool, which ensures validation process. The network traffic, which characterizes the behavior of the network, is collected by NetFlow technology, which generates network flows. These flows are consequently used by the designed tool used for validation of required network parameters. This process overall verifies whether the main computer network requirements have been met or not.

Support of multicast routing and its implementation is one of the main goals in nowadays computer networks. Adapting new technology could be often challenging and connected with difficulties. For this reason its better to try it in some simulating enviroment and implement it only after successful results of tests and simulations. The aim of this diploma thesis is to familiarize the reader with the multicast routing, describe the possibilities of network testing in OMNeT++ and come up with new multicast routing framework for this discrete simulation tool.

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.