Global ETD Search

121	Uma solução baseada em SNMP para gerenciamento de dispositivos de rede com suporte à virtualização Daitx, Fábio Fabian January 2011 (has links) A virtualização de rede surgiu como uma alternativa para contornar as limitações no uso compartilhado da infraestrutura atual da Internet. Com a virtualização, sob uma mesma estrutura física, ou substrato, é possível a construção de múltiplas redes virtuais, cada uma das quais empregando seus próprios protocolos, mecanismos de endereçamento e políticas de forma independente e isolada. Essas redes são formadas por roteadores, interfaces e enlaces virtuais mapeados sobre componentes reais. Por serem desacopláveis, os elementos virtuais trazem uma grande flexibilidade, sendo possível a construção de múltiplas redes sobrepostas para usuários com demandas distintas, por exemplo. Roteadores virtuais podem migrar de um roteador físico para outro, conforme necessidades de manutenção ou balanceamento de carga. Além disso, a possibilidade de se conduzir experimentos de rede em uma estrutura real, sujeita as condições de utilização e de tráfego que normalmente serão encontradas na prática, sem que se precise interromper a operação da rede, traz a possibilidade de se instalar poderosos e sofisticados ambientes de teste (testbeds ). Nesse ambiente, contudo, existem desafios de pesquisa a serem tratados e questões em aberto, em especial com relação ao gerenciamento de dispositivos. Em uma rede com suporte a virtualização, os roteadores físicos precisam ser gerenciados para que roteadores virtuais possam ser criados, modificados, duplicados, destruídos e movimentados. As interfaces de gerenciamento atuais, porém, não suportam tais ações de forma efetiva, obrigando o administrador dos dispositivos a realizar intervenções manuais através de interfaces de linha de comandos (CLIs) não padronizadas. Existe, assim, a necessidade de se definir uma interface de gerenciamento adequada para roteadores físicos que abrigam roteadores virtuais. Tendo como objetivo abordar estas questões, este trabalho consiste na investigação de uma solução para gerenciar roteadores virtuais. Para isto foram levantadas e definidas as principais ações de gerenciamento necessárias aos dispositivos, de forma integrada, visando a definição de uma interface padronizada de gerencia- mento para cenários heterogêneos de utilização. / Network virtualization emerged as an alternative to overcome limitations on use of the shared infrastructure of current Internet. With virtualization, over the same physical structure, or substrate, it is possible to build multiple virtual networks, each of them employing its own protocols, addressing mechanisms and policies, on an isolated and independent way. These networks are formed by virtual routers, interfaces and links mapped to real components. Because they are detachable, the virtual elements bring a great flexibility, being possible constructing many overlaid networks for users with different demands, for example. Virtual routers can migrate from one physical router to another as needed form maintenance or load balancing. Besides, the possibily of running network experiments in a real structure, subject to the conditions of use and traffic that will normally be encountered in practice, without interrupting network operation, make it possible to install powerfull and sofisticated testbeds. In such environment, however, there are research challenges to be managed and open questions, specially related to devices management. In a network with virtu- alization support, physicall routers must be managed so that virtual routers can be created, modified, copied, removed and moved. Nevertheless, current management interfaces do not support such action in an effictive way, compelling the devices manager to make manual interventions through non standardized command line interfaces (CLIs). So, there exist the need to define an adequate management interface for physicall routers that host virtual routers. Having as an objective to address these questions, this work consist in investi- gating a solution to manage virtual routers. For this, were raised and defined the main management actions required for devices, through an integrated way, aiming to define a standardized management interface for heterogeneous use scenarios. Redes : Computadores Gerencia : Redes : Computadores Virtual router Network virtualization MIB (management information base)
122	Uma solução baseada em SNMP para gerenciamento de dispositivos de rede com suporte à virtualização Daitx, Fábio Fabian January 2011 (has links) A virtualização de rede surgiu como uma alternativa para contornar as limitações no uso compartilhado da infraestrutura atual da Internet. Com a virtualização, sob uma mesma estrutura física, ou substrato, é possível a construção de múltiplas redes virtuais, cada uma das quais empregando seus próprios protocolos, mecanismos de endereçamento e políticas de forma independente e isolada. Essas redes são formadas por roteadores, interfaces e enlaces virtuais mapeados sobre componentes reais. Por serem desacopláveis, os elementos virtuais trazem uma grande flexibilidade, sendo possível a construção de múltiplas redes sobrepostas para usuários com demandas distintas, por exemplo. Roteadores virtuais podem migrar de um roteador físico para outro, conforme necessidades de manutenção ou balanceamento de carga. Além disso, a possibilidade de se conduzir experimentos de rede em uma estrutura real, sujeita as condições de utilização e de tráfego que normalmente serão encontradas na prática, sem que se precise interromper a operação da rede, traz a possibilidade de se instalar poderosos e sofisticados ambientes de teste (testbeds ). Nesse ambiente, contudo, existem desafios de pesquisa a serem tratados e questões em aberto, em especial com relação ao gerenciamento de dispositivos. Em uma rede com suporte a virtualização, os roteadores físicos precisam ser gerenciados para que roteadores virtuais possam ser criados, modificados, duplicados, destruídos e movimentados. As interfaces de gerenciamento atuais, porém, não suportam tais ações de forma efetiva, obrigando o administrador dos dispositivos a realizar intervenções manuais através de interfaces de linha de comandos (CLIs) não padronizadas. Existe, assim, a necessidade de se definir uma interface de gerenciamento adequada para roteadores físicos que abrigam roteadores virtuais. Tendo como objetivo abordar estas questões, este trabalho consiste na investigação de uma solução para gerenciar roteadores virtuais. Para isto foram levantadas e definidas as principais ações de gerenciamento necessárias aos dispositivos, de forma integrada, visando a definição de uma interface padronizada de gerencia- mento para cenários heterogêneos de utilização. / Network virtualization emerged as an alternative to overcome limitations on use of the shared infrastructure of current Internet. With virtualization, over the same physical structure, or substrate, it is possible to build multiple virtual networks, each of them employing its own protocols, addressing mechanisms and policies, on an isolated and independent way. These networks are formed by virtual routers, interfaces and links mapped to real components. Because they are detachable, the virtual elements bring a great flexibility, being possible constructing many overlaid networks for users with different demands, for example. Virtual routers can migrate from one physical router to another as needed form maintenance or load balancing. Besides, the possibily of running network experiments in a real structure, subject to the conditions of use and traffic that will normally be encountered in practice, without interrupting network operation, make it possible to install powerfull and sofisticated testbeds. In such environment, however, there are research challenges to be managed and open questions, specially related to devices management. In a network with virtu- alization support, physicall routers must be managed so that virtual routers can be created, modified, copied, removed and moved. Nevertheless, current management interfaces do not support such action in an effictive way, compelling the devices manager to make manual interventions through non standardized command line interfaces (CLIs). So, there exist the need to define an adequate management interface for physicall routers that host virtual routers. Having as an objective to address these questions, this work consist in investi- gating a solution to manage virtual routers. For this, were raised and defined the main management actions required for devices, through an integrated way, aiming to define a standardized management interface for heterogeneous use scenarios. Redes : Computadores Gerencia : Redes : Computadores Virtual router Network virtualization MIB (management information base)
123	Implementation of data-collection tools using NetFlow for statistical analysis at the ISP level / Implementation av datainsamlingsverktyg med NetFlow på ISP-nivå för statistisk analys av datatrafik Karlström, Daniel January 2012 (has links) Defending against Dos- and DDoS attacks is difficult to accomplish; finding and filtering out illegitimate traffic from the legitimate flow is near impossible. Taking steps to mitigate or even block the traffic can only be done once the IP addresses of the attackers are known. This is achievable by monitoring the flows to- and from the target and identifying the attacker's IP addresses, allowing the company or their ISP to block the addresses itself by blackholing them (also known as a null route). Using the IP accounting and monitoring tool “pmacct”, this thesis aims to investigate whether or not the pmacct suite is suited for larger installations when tracking and mitigating DDoS-attacks, such at an Internet Service Provider (ISP). Potential problems are the amount of traffic that need to be analyzed and the computational power required to do it. This thesis also provide information about the pmacct suite at large. The conclusions are positive, indicating it does scale up to handle larger installations when given careful consideration and planning. / Att försvara sig mot DoS-och DDoS-attacker är svårt att åstadkomma; att hitta och filtrera ut illegitim trafik från det legitima flödet är nästan omöjligt. Att vidta åtgärder när en sådan attack upptäcks kan endast göras när IP-adresserna från angriparna är kända. Detta kan uppnås genom att man övervakar trafikflödet mellan målet för attacken och angriparna och ser vilka som sänder mest data och på så sätt identifierar angriparna.. Detta tillåter företaget eller dess ISP att blockera trafiken ifrån dessa IP-adresser genom att sända trafiken vidare till ingenstans. Detta kallas blackhole-routing eller null-routing. Genom att använda redovisnings- och övervakningsprogrammet pmacct syftar denna uppsats på att undersöka hurvida pmacct-sviten är lämpad för större installationer när det gäller att spåra och förhindra DDoS-attacker, såsom hos en Internetleverantör eller dylikt. Potentialla problem som kan uppstå är att mängden trafik som måste analyserar blir för stor och för krävande. Denna avhandling går även igenom pmacct-verktyget i sig. Slutsatserna är lovande, vilket indikerar att den har potential av att kunna hantera sådana stora miljöer med noggrann planering. pmacct statistical analysis bgp peer peering routing route quagga virtual router virtual router linux graph graphing mrtg database mysql script scripting python bash libpcap mdh data collection data collection collecting ISP internet service provider DoS DDoS attack pmacct statistisk analys bgp peer peering peera routing route quagga virtuell router virtuell router linux graf grafa mrtg databas mysql script scripting python bash libpcap mdh datainsamling insamling data ISP internetleverantör DoS DDoS attack Computer Engineering Datorteknik
124	Návrh laboratorních úloh pro výuku síťových technologií a protokolů / Laboratory exercises explaining network technologies and protocols Coufal, Tomáš January 2019 (has links) Diploma thesis deals with creation of laboratory exercises in ns-3 environment. Each one of three exercises consists of theoretical introduction and instructions to carry out the simulation. The first exercise´s topic is routing protocol BGP. The second exercise is focused on transport protocols TCP, UDP, SCTP. In the last exercise, the basic network devices and topologies are simulated. The ARP and RIPv2 protocols are simulated as well.
125	Spojovací systémy založené na IP telefonii / Communication systems based on IP telephony Zimek, Josef January 2008 (has links) My master’s thesis is focused on designing and creating communication network, which provides communication between two independent networks through encrypted tunnel. My solution is based on routers formed by older personal computers with FreeBSD like a operating system. Between routers is created static encrypted tunnel by using IPSec protocol. Voice services provides packet oriented exchange Asterisk with support of signaling protocol SIP. This solution can be used eg. for connecting remote branch to headquarters of company and then can branch utilize shrared resources. To headquarters can connect also remote workers from their home. In this case are used SSL certificates to authentication of user. This scenario is very required today.
126	Analýza audio kodeků užívaných při IP telefonii / Analysis of Audio Codecs Applied in IP telephony Hlavica, Michal January 2012 (has links) Issue of this diploma thesis is focused on analysis of audio codecs used within IP telephony. Attention of teoretical part is given mostly to audio codecs according to ITU-T recommendations, but also to signaling protocols used here. For practical part of analysis is chosen router Cisco 2821 and IP phones Cisco 7975G. Configuration is done over operating system Cisco IOS. Chosen signaling protocol is SCCP. For analysis itself are chosen 2 analysers – L-580FX and Fluke NetTool. These are used in combination with program Wireshark. Analysed parameters are latency, packet lost, bandwidth, jitter and mean opinion score. Measured values are presented in graphs and tables and they are discussed. Next output of the thesis is laboratory excercise, which deals with analysis of audio codecs.
127	40GbE směrovač pro operační systém GNU/Linux / Towards 40GbE GNU/Linux Router Luštický, Josef January 2015 (has links) Účelem této práce je popis protokolu 40Gb Ethernet, popis směrovacího procesu v jádře Linux a navrhnout a provést testování výkonnosti směrování se síťovým adaptérem pro 40Gb Ethernet. Výsledky a nastavení pro získání maximální výkonnosti směrování jsou dále popsány v této práci.
128	Using Hard Macros to Accelerate FPGA Compilation for Xilinx FPGAs Lavin, Christopher Michael 22 January 2012 (has links) (PDF) Field programmable gate arrays (FPGAs) offer an attractive compute platform because of their highly parallel and customizable nature in addition to the potential of being reconfigurable to any almost any desired circuit. However, compilation time (the time it takes to convert user design input into a functional implementation on the FPGA) has been a growing problem and is stifling designer productivity. This dissertation presents a new approach to FPGA compilation that more closely follows the software compilation model than that of the application specific integrated circuit (ASIC). Instead of re-compiling every module in the design for each invocation of the compilation flow, the use of pre-compiled modules that can be "linked" in the final stage of compilation are used. These pre-compiled modules are called hard macros and contain the necessary physical information to ultimately implement a module or building block of a design. By assembling hard macros together, a complete and fully functional implementation can be created within seconds. This dissertation describes the process of creating a rapid compilation flow based on hard macros for Xilinx FPGAs. First, RapidSmith, an open source framework that enabled the creation of custom CAD tools for this work is presented. Second, HMFlow, the hard macro-based rapid compilation flow is described and presented as tuned to compile Xilinx FPGA designs as fast as possible. Finally, several modifications to HMFlow are made such that it produces circuits with clock rates that run at more than 75% of Xilinx-produced implementations while compiling more than 30X faster than the Xilinx tools. FPGA rapid prototyping design flow hard macros Xilinx XDL RapidSmith HMFlow open source placer router Electrical and Computer Engineering
129	Erkennung und Unterbindung der DDoS-Teilnahme in Heimroutern: Analyse und Implementierung von Erkennungsmechanismen Heinrich, Lukas 22 December 2023 (has links) DDoS-Angriffe und die für diese genutzten Botnetze werden u. a. durch die zunehmende Verbreitung von IoT-Geräten stetig größer. Aufgrund der Vorteile einer frühzeitigen Unterbindung solcher Angriffe ist eine effektive Erkennung der DDoS-Teilnahme in Heimroutern sinnvoll. Diese Arbeit analysiert aktuell verbreitete DDoS-Angriffstypen und entwickelt sowie sammelt verschiedene Erkennungsmechanismen aus der Literatur. Mithilfe ausführlicher Untersuchungen und Tests bezüglich Filterverhalten und Ressourcenbedarf der Erkennungsmechanismen konnten DDoS-Angriffstypen identifiziert werden, welche effektiv im Heimrouter erkannt und unterbunden werden können.:1 Einleitung 1.1 Problemstellung 1.2 Zielstellung 2 Verbreitetste DDoS-Angriffstypen 2.1 Source IP Spoofing 2.2 Reflection/Amplification 2.2.1 SSDP 2.2.2 WS Discovery 2.2.3 QUIC-Reflection 2.3 TCP-Floods 2.3.1 SYN-Flood 2.3.2 RST- und FIN-Flood 2.3.3 SYN-ACK-Flood 2.3.4 ACK-Flood 2.4 UDP-Flood 2.5 Direkte Application-Layer-Angriffe 2.6 Übersicht 3 Erkennung 3.1 Source IP Spoofing 3.2 SSDP & WS Discovery 3.3 TCP 3.3.1 SYN-Flood 3.3.2 RST- und FIN-Flood 3.3.3 SYN-ACK-Flood 3.3.4 ACK-Flood 3.4 UDP 3.5 Allgemeine Erkennung 3.5.1 MULTOPS 3.5.2 TOPS 3.5.3 D-WARD 4 Implementierung 4.1 Source IP Spoofing 4.2 SSDP & WS Discovery 4.3 TCP (ohne SYN) 4.4 SYN-Flood 4.4.1 SYN Paketratenlimitierung 4.4.2 SYN Proxy 5 Untersuchung 5.1 Tests 5.1.1 Implementierungskomplexität 5.1.2 Speicher- und Rechenkapazitätsbedarf 5.1.3 Filterverhalten 5.2 Andere Erkennungsmethoden 5.2.1 Implementierungskomplexität 5.2.2 Speicher- und Rechenkapazitätsbedarf 5.2.3 Filterverhalten 5.3 Diskussion 6 Fazit & Ausblick Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis / DDoS attacks and the botnets used for them are constantly growing due to the increasing spread of IoT devices, among other things. Due to the advantages of stopping such attacks at an early stage, effective detection of DDoS participation in home routers makes sense. This thesis analyses currently widespread DDoS attack types and develops and collects various detection mechanisms from the literature. With the help of detailed investigations and tests regarding filter behaviour and resource requirements of the detections mechanisms, DDoS attack types were identified that can be effectively detected and prevented in the home router.:1 Einleitung 1.1 Problemstellung 1.2 Zielstellung 2 Verbreitetste DDoS-Angriffstypen 2.1 Source IP Spoofing 2.2 Reflection/Amplification 2.2.1 SSDP 2.2.2 WS Discovery 2.2.3 QUIC-Reflection 2.3 TCP-Floods 2.3.1 SYN-Flood 2.3.2 RST- und FIN-Flood 2.3.3 SYN-ACK-Flood 2.3.4 ACK-Flood 2.4 UDP-Flood 2.5 Direkte Application-Layer-Angriffe 2.6 Übersicht 3 Erkennung 3.1 Source IP Spoofing 3.2 SSDP & WS Discovery 3.3 TCP 3.3.1 SYN-Flood 3.3.2 RST- und FIN-Flood 3.3.3 SYN-ACK-Flood 3.3.4 ACK-Flood 3.4 UDP 3.5 Allgemeine Erkennung 3.5.1 MULTOPS 3.5.2 TOPS 3.5.3 D-WARD 4 Implementierung 4.1 Source IP Spoofing 4.2 SSDP & WS Discovery 4.3 TCP (ohne SYN) 4.4 SYN-Flood 4.4.1 SYN Paketratenlimitierung 4.4.2 SYN Proxy 5 Untersuchung 5.1 Tests 5.1.1 Implementierungskomplexität 5.1.2 Speicher- und Rechenkapazitätsbedarf 5.1.3 Filterverhalten 5.2 Andere Erkennungsmethoden 5.2.1 Implementierungskomplexität 5.2.2 Speicher- und Rechenkapazitätsbedarf 5.2.3 Filterverhalten 5.3 Diskussion 6 Fazit & Ausblick Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis
130	Efficient Positioning Technique for Multi-Interface Multi-Rate Wireless Mesh Networks Wang, Junfang January 2010 (has links) No description available. Computer Science Mesh Router Placement Mesh Client Association Multiply Transmission Rate Multiply Transmission Range Virtual Force Wireless Mesh Network

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