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1	Improving the Quality of Multicast Networks by Using the OPNET Modeler / Förbättra kvaliteten på Multicast-nätverk under OPNET Modeler VIENJIPURAM, KRISHNA KUMARAN, ABDUL, ASMEER BABU January 2010 (has links) This thesis presents different Internet Protocol (IP) multicasting design models and together with their implementation methods in OPNET Modeler 14.5. The models presented in this report are designed for handling various types of advanced multimedia applications and services when using the multicast communication paradigm. The architectural models presented in this thesis are independent of the routing protocols used as well as of the underlying networking environment. Several exiting challenges related to high bandwidth requirements, low network delay, and jitter are discussed together with these design models, and are simulated using the OPNET Modeler. The emerging demands for new multicast capable applications, for both real-time and non real-time traffic are considered together in this report in order to better evaluate multicast traffic requirements. Efficient routing methods, group management policies, and shortest path algorithms are also discussed in the proposed models. The pros and cons of IP multicasting are described using the Protocol Independent Multicast Sparse Mode (PIM-SM) method, in the highlight of the proposed design models. Several results related to link utilization, end-to-end delay, packet loss, PIM control traffic, Internet Group Management Protocol (IGMP), and network convergence are obtained by using already available statistical methods and modules from OPNET Modeler. Our major contribution with this thesis work relates to components associated with network convergence, routing delay, and processing delay. These components are illustrated in this thesis using various OPNET metrics. Moreover, several issues related to protocol scalability, supportability, performance optimization and efficiency are also presented by using OPNET’s build in reports, i.e., executive flow and survivability analysis reports. / 0735609277 IGMP PIM-DM PIM-SM MBONE DVMRP BGP EIGRP
2	Modelování multicastových distribučních stromů a klientských protokolů / Multicast Distribution Trees Modelling in OMNeT++ Malik, Adam January 2013 (has links) 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.
3	Protocolo multiciclos para automa??o hospitalar sobre Multicast com IEEE 802.3 utilizando Valentim, Ricardo Alesxandro de Medeiros 31 October 2008 (has links) Made available in DSpace on 2014-12-17T14:54:50Z (GMT). No. of bitstreams: 1 RicardoAMV.pdf: 3496779 bytes, checksum: 5e48ba1a2b67cf4883df0bcfaab403ea (MD5) Previous issue date: 2008-10-31 / The concepts of the industrial automation are being incorporated in the medical area, in other words, they also pass to be applied in the hospital automation. In this sense, researches have been developed and have usually been approached several of the problems that are pertinent to the processes that can be automated in the hospital environment. Considering that in the automation processes, an imperative factor is the communication, because the systems are usually distributed, the network for data transference becomes itself an important point in these processes. Because this network should be capable to provide the exchange of data and to guarantee the demands that are imposed by the automation process. In this context, this doctorate thesis proposed, specified, analyzed and validated the Multicycles Protocol for Hospital Automation (MP-HA), which is customized to assist the demands in these automation processes, seeking to guarantee the determinism in the communications and to optimize the factor of use of the mean of transmission / Os conceitos da automa??o industrial j? est?o a algum tempo sendo incorporados na ?rea m?dica, passando tamb?m a ser utilizados na automa??o hospitalar. Nesse sentido, v?rias pesquisas t?m sido desenvolvidas e geralmente tem abordado v?rios dos problemas que s?o pertinentes aos processos que podem ser automatizados no ambiente hospitalar. Considerando que, nos processos de automa??o, um fator imperativo ? a comunica??o, visto que os sistemas geralmente s?o distribu?dos, a rede para transfer?ncia de dados passa a ser um elemento fundamental desses processos, pois devem ser capazes de prover a troca de dados e garantir ?s exig?ncias impostas pelo processo de automa??o. ? nesse contexto, que a presente tese de doutorado prop?s, especificou, validou e analisou o PM-AH (Protocolo Multiciclos para Automa??o Hospitalar). O PM-AH ? customizado para atender as exig?ncias dos processos de monitoramento de pacientes (redes de controle) em ambientes hospitalares e visa garantir o determinismo nas comunica??es, otimizando o fator de utiliza??o do meio de transmiss?o Automa??o hospitalar IGMP Snooping Tempo real Hospital automation IGMP Snooping Real time CNPQ::ENGENHARIAS::ENGENHARIA ELETRICA
4	Architektury systémů na Internetu se skupinovým adresováním / Architectures of Internet-Based Systems with Multicasting Veselý, Vladimír January 2009 (has links) With rapid expansion of interest in multimedia and distributed computing applications across the Internet increases importance of optimized delivery of group traffic. According to current situation the best practice to achieve this goal is multicasting. This masters thesis summarizes multicasting methods and facts. Also it draws conclusions from practical application of presented information on commercial project.
5	Infrastructure sécurisée de routage multipoint : le point de vue de l'opérateur réseau Khallouf, Zainab 15 March 2006 (has links) (PDF) Le multicast est un mécanisme efficace qui permet à un grand nombre de récepteurs de recevoir le même contenu puisqu'un paquet traverse une fois et une seule un lien donné. Le multicast a été étudié de longue date et pourtant à ce jour aucun déploiement à grande échelle n'a eu lieu. Aujourd'hui l'une des raisons du non déploiement du multicast auprès des opérateurs de réseaux est la problématique de la sécurité. Or, deux niveaux complémentaires de sécurité doivent être considérés : (1) la sécurité applicative qui est essentiellement la préoccupation des clients finaux et les fournisseurs de contenu, et (2) la sécurité de l'infrastructure de routage multicast, qui est la préoccupation de l'opérateur de réseau. <br />Ce travail considère la sécurité de l'infrastructure multicast du point de vue de l'opérateur de réseau. Or, l'opérateur est essentiellement concerné par un problème de « continuité de service en toutes circonstances », même dans le cas ou son réseau est victime d'une attaque.<br />Dans cette thèse nous identifions les attaques possibles, nous les classons selon leur dangerosité pour l'opérateur, et identifions divers mécanismes de sécurité pour y faire face. Cette étude révèle que l'infrastructure est fortement vulnérable aux attaques DoS consommant les ressources de réseau, ce dernier devenant alors lent voir indisponible. Ces attaques sont faciles à lancer de la périphérie de réseau (intentionnellement ou non) en utilisant les protocoles de gestion de groupe IGMP/MLD. Notre étude révèle également les limites des approches proposées pour répondre à ces attaques. A la lumière de l'analyse détaillée de la problématique, des vulnérabilités, et des solutions actuelles, nous proposons une nouvelle approche pour aider le réseau de l'opérateur à se défendre contre les attaques basées sur IGMP ou MLD. Notre proposition suit une approche pragmatique et flexible, qui garantit qu'elle sera facilement déployée dans les infrastructures existantes, et vise également à protéger les clients légitimes en cas d'attaque. multicast protocoles de routage multicast opérateur réseau IGMP/MLD sécurité infrastructure attaques DoS
6	Aplikace pro monitorování multicastových relací / Monitoring Application for Multicast sessions Kopecký, Martin January 2009 (has links) This work deals with a monitoring application for multicast sessions. The general aim is to develop the application for monitoring multicast sessions from network elements of a laboratory computer network. The first part describes possibilities of monitoring computer networks in terms of monitoring techniques and protocols. The second part contains a topology of the laboratory computer network and several basic commands for setting of the multicast in Cisco IOS. The third part is devoted to the developed application for monitoring the multicast in Java language. The last part describes the testing on an actual multicast network and an example of such testing is stated there.
7	Contributions pour la réduction du temps de zapping dans un réseau IPTV Multicast / Contributions for the zapping time reduction in IPTV Multicast network Sarni, Mounir 14 December 2010 (has links) Cette thèse concerne l'investigation détaillée du problème du temps de zapping dans les réseaux d'opérateurs offrant un service IPTY basé sur la technologie multicast. Cette investigation a conduit à plusieurs contributions qui permettent de substantiellement améliorer le temps de zapping dans ce type de réseau. Notre première contribution concerne la partie purement réseau. Nous avons proposé d'optimiser le processus de changement de chaîne et ceci pour chaque version du protocole IGMP. Cette optimisation réduit la latence due au réseau sans pour autant augmenter la consommation de bande passante d'une manière significative. Nous avons modélisé le service IPTV Multicast pour estimer les pics de consommation de la bande passante pour permettre à l'opérateur de dimensionner son réseau. La deuxième contribution concerne la partie traitement du flux IPTV par le récepteur. Dans cette partie, nous avons proposé d'associer au flux principal un flux secondaire, version retardée du principal. La construction du flux secondaire se fait en donnant une priorité élevée aux paquets transportant des éléments d'une I-Frame par rapport à d'autres types d'éléments (P Frame, B-Frame, Voix et Data). Cette nouvelle règle de construction permet de réduire le délai d'attente de la première IFrame nécessaire pour commencer la phase de décodage tout en réduisant le temps de remplissage du buffer. Dans un environnement réel, nous avons évalué cette contribution et constaté une réduction remarquable du temps de zapping. / This thesis involves a detailed investigation of the problem of IPTV zapping time in networks of operators providing IPTV service based on multicast technology. This investigation led to some contributions that can substantially improve the channel change time in this type of network.Our first contribution concerns the pure network. We proposed an optimization of the channels changing process for each version of the IGMP protocol. This optimization reduces network latency without significantly increasing the bandwidth consumption. We proposed also a model of multicast IPTV service that we used to estimate the maximum bandwidth demand. This model enables the operator to size the bandwidth availability in its network.The second contribution relates to the processing part of stream IPTV on the receiver. In this section, we proposed to combine the main flow to a secondary flow, delayed version of the main stream. The construction of the secondary stream is clone by giving high priority to packets carrying elements of an I-frame compared to other types of elements (P-Frame, B-Frame, Voice and Data). This rule of construction can reduce the First I-Frame Delay required to start the decoding phase and at the same time reduce the Buffering Delay. In a real environment, we evaluated this contribution and measured a remarkable decline of the zapping time with our proposal. FTTH IPTV Multicast Zapping IGMP MPEG ERAS Triple play Fiber to the premises Internet Protocol television Multicast Zapping Internet Group Management Protocol MPEG ERAS Triple play
8	Návrh testů komunikace se skupinovým adresováním v IP / Design of IP Multicast Communication Tests Stehura, Igor January 2008 (has links) This masters thesis is about mutlicast. There are explained 2nd and 3th layers of the ISO/OSI model multicast addressing. Routers in a network use multicast routing protocols to optimally route multicast packet through the network, this is also in this project. These multicast protocols are DVMRP, protocol PIM in his two modes, PIM Sparse Mode and PIM Dense Mode. Protocol DVMRP uses protocol IGMP, which is described as well. At practical section of this masters thesis is presented connections, by which tests was executed.
9	4G LTE : eMBMS with MBSFN Service Simulation using OPNET Walid, Abdelrahman January 2014 (has links) Long Term Evolution (LTE) known in the market as 4G LTE, it is an evolution of the GSM/UMTS standard. The overall aim of LTE was to provide a new radio access technology focusing on packet-switched data only. LTE has provided a new peak download rates, low data transfer latencies, and improved the support for mobility. 3Th Generation Partnership Project (3GPP) specialized that LTE released 10 and beyond known as LTE-advanced it is the second evolution of LTE. It has some services such as Coordinated Multipoint Transmission and Reception (CoMP), evolved Multimedia Broadcast and Multicast Service (eMBMS) with Multicast-Broadcast Single-Frequency Network (MBSFN). The development still continuous on LTE-advanced, it is intended to meet the requirement of advanced application that will become common in the wireless marketplace in future. The goals of this project is to simulate one of LTE-A services on LTE standard such as CoMP or/and eMBMS with MBSFN using OPENT LTE, and measure some statistic such as spectral efficiency and also some other statistics, describe centralization vs. decentralization in LTE, and synchronization in the base station in LTE. OPNET LTE support eMBMS with MBSFN, and don’t support CoMP, the simulation has been done by using eMBMS with MBSFN. Finally the objectives of the project has achieved, the result show that when eMBMS with MBSFN is implemented the throughput increased in the downlink to about 5.52 Mbps and in the uplink to about 5.18 Mbps, and also the system spectral efficiency increased in eNB1 from about 10.25 (bits/s/Hz/cell) to about 13.75 (bits/s/Hz/cell) and in eNB2 from about 10.25 (bits/s/Hz/cell) to about 17.25 (bits/s/Hz/cell). The project also answers if it is possible to have centralization in LTE, describe synchronization in the base station in LTE, and if OPNET is useful for big research. 3G 3GPP 4G CoMP CSI CSI-IM CSI-RS eMBMS eNB EPC EPS E-UTRAN GSM HSPA IGMP IGRP ITU-T LTE LTE-A MAC MBSC MBSFN MCE MCS MFN MME OFDM OFDMA OPNET OSPF PDN-GW PDSCH PMCH PUCCH PUSCH QoS SAE SC-FDMA S-GW TDD TD-SCMDA UE UTMS WCDMA. Computer Engineering Datorteknik

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