The diploma thesis deals with analysis and modeling of power line communication using NS-3. The introduction part summarizes basic information about PLC technology, distribution grids, and broadband standards. This is followed by the analysis of the transmission line and modulation method. Furthermore, the simulation tool and possibilities of its extension are described. The influence of different cross-section and type of line on channel capacity is examined in the practical part of this paper. The influence of repeaters on bitrate is examined as well. The medium-voltage line was implemented and further scenarios dealing with bitrate or optimal level of noise. The focus of the last part is to find the repeaters on the path and to determine the capacity and bitrate on the path of the large topology.

Tato diplomová práce se zabývá technologii blockchain se zaměřením na konsenzus protokoly, zvláště protokoly typu proof-of-stake. V této práci naleznete popis těchto protokolů následovaný popisem konsenzu v technologii blockchain. Prvotní kapitoly detailněji popisují a porovnávají jednotlivé proof-of-stake protokoly na základě teoretických znalostí. Druhá část práce se zaobírá návrhem a implementací testbedu, který je následně použitý pro praktické porovnání proof-of-stake protokolů. V závěrečné částí práce je diskutováno nad zjištěnými výsledky pozorováním testbedu a zjištěnými vlatnostmi protokolů. Na tomto základě práce ve svém konci naznačuje další směřování consesus protokolů, ba jejich případné zlepšení, a zvláště proof-of-stake typu protokolů.

The diploma thesis focuses on the description of LPWAN (Low Power Wide Area Network) technologies for use in IoT (Internet of Things) communication scenarios. The theoretical part compares communication technologies operating in the license-exempt frequency band, i.e. Sigfox and LoRaWAN (Long Range Wide Area Network). Furthermore, technologies using the licensed frequency spectrum are discussed, specifically, attention is focused on NB-IoT (Narrow Band IoT). Emphasis is placed on LoRaWAN technology and the properties of the unlicensed frequency band below the 1 GHz, which is utilized by this technology. The practical part of the thesis consists of the evaluation of simulation scenarios using an integrated module in the simulation environment NS-3 (Network Simulator 3). Attention is focused mainly on the analysis of data transmission success using selected communication parameters of LoRaWAN technology. The obtained simulation outputs with a focus on mMTC (massive Machine-Type Communication) communication scenarios confirm the relationship between the number of end devices and gateways, communication distance and transmission reliability, or the limit value for the duty cycle.

The diploma thesis "QoS model for Mobile ad hoc network" focuses on the quality of services in MANET (Mobile Ad-hoc) networks. It describes MANET networks and covers the theoretical analysis of routing protocols with QoS (Quality of Service) support. Furthermore, there is processed the creation process of model MANET networks with the routing protocol DSDV (Destination-Sequenced Distance Vector) in the simulation environment NS-3 (Network Simulator 3) and its extension of QoS support. The used QoS model is subsequently modified to improve core operating parameters. The implementation of QoS parameters as well as the improvement of delay and jitter (the delay between selected packets) is verified by the functional simulation.

The main task of this master’s thesis is to simulate the routing protocol AODV (Adhoc On-Demand Distance Vector Routing) to the Network Simulator ns-3 environment, and to realize a model of MANET (Mobile Ad-hoc Network) network with the support of Quality Of Service (QoS). Further implement the protocol AODV in real devices and the involvement of such nodes in the simulation process using the simulator ns-3. This work provides the theoretical basics: it deals with the primary characteristics of MANET, describes in detail the routing protocols MANET with support of QoS, provides information about the Network Simulator ns-3 simulation environment, describes in detail the existing implementation solutions of the protocol AODV in to real devices and provides information about the methods of involvement real devices to the simulation.

This thesis deals with the powerline communication focusing on the simulations of channel transfer functions. The introduction summarizes basic information about PLC followed by the analysis of the available PLC Software simulator (implemented in NS-3) and the analysis of implemented noises and interferences and its extensions. One chapter is devoted to possibilities of link capacity calculation. Within the thesis, various methods of calculation of primary parameters of transmission line were implemented and the simulator was compared with other freely available simulators. Subsequently, simulations were carried out focused on channel transfer functions in different topologies, on the impedance changes of branch, on the lengths of branch, and changes in the direct path between communicating nodes.

The theoretical part of the thesis focuses on history and development of M2M com- munication, Wireless M-Bus protocol and NS-3 Network Simulator. It briefly describes characteristics of M2M communication, Wireless M-Bus and NS3 simulator. Physical and link layer of Wireless M-bus protocol are described in great detail to provide basics needed for understanding and orientation in the topic. Practical part of the thesis is focused on structure of used Simple Wireless module and basic simulation scenerio is built. The scenerio demostrates basic functions of the module.

This thesis focuses on the description of nanocommunication networks, models for wireless communication networks and the description of motion in nanocommunication networks. The practical part describes the settings of the simulation scenarios for the definition of Brownian motion. Description is made for the simulation software NS-3 and N3Sim. In this thesis, the measured results of the simulations are summarized in tables and graphs. From the measured results the regression analysis is prepared. General summary of the results is provided at the end of thise thesis.

Key tasks of this work are to create the simulation of a wireless network in ns-3 and to stream a video over this network by using MPEG-DASH technology. It describes the tools and methods how to encode a video according to MPEG-DASH. It is explained what is needed to run video server, which uses MPEG-DASH technology to stream videos. Then, it is described how a simulation of wired and wireless WiFi and LTE networks is created. The simulation starts a server and shows how it works, how many nodes can be used and chooses suitable segment duration.

The diploma thesis deals with the issue of data transmission over power lines, focusing on simulation transmission functions. The theoretical part summarizes basic information on PLC technology and distribution networks, followed by analysis PLC simulator implemented in NS-third In the practical part of the thesis is described implementation of individual types of underground and overhead lines to the PLC simulator. Also been carried simulation scenarios for a simple topology and were designed own simulation scenarios for extended topology and simulations have been carried out various kinds of interference on communication.