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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Network Traffic Simulation and Generation / Network Traffic Simulation and Generation

Matoušek, Jiří January 2011 (has links)
Development of computer networks able to operate at the speed of 10 Gb/s imposes new requirements on newly developed network devices and also on a process of their testing. Such devices are tested by replaying synthetic or previously captured network traffic on an input link of the tested device. We must be able to perform both tasks also at full wire speed. Current testing devices are either not able to operate at the speed of 10 Gb/s or they are too expensive. Therefore, the aim of this thesis is to design and implement a hardware accelerated application able to generate and replay network traffic at the speed of 10 Gb/s. The application is accelerated in the FPGA of the COMBOv2 card and it also utilizes the NetCOPE platform. Architecture of the application is modular, which allows easy implementation of different modes of operation. The application implements both capturing and replaying network traffic at full wire speed, but traffic can be limited to a specified value of bitrate at the output. The thesis is concluded by a comparison of the implemented application and the packet generator implemented on the NetFPGA platform. According to this comparison, the implemented application is better than the NetFPGA packet generator.
212

Zefektivnění analýzy počítačové sítě 10Gbit/s / Perfecting the analysis of 10Gbit/s computer network

Ťápal, Tomáš January 2013 (has links)
The master’s thesis consists of several parts. Describes the technology 10 Gbps Ethernet. Analyzer Ixia and Endace presents, especially their use for traffic analysis and stress testing the network devices. It deals with documents RFC concerning the routers and switch testing. Thesis includes the reports of tests switches and router performed by RFC 2544 and RFC 2889 documents. Part of the thesis is dedicated to COMBO FPGA cards. Documentations to the analyzers is created in this thesis and macro is on the CD for presentation of measurement results.
213

A Meta Analysis of Gigabit Ethernet over Copper Solutions for Cluster-Networking

Hoefler, Torsten, Rehm, Wolfgang 28 June 2005 (has links)
The IEEE Standard for Gigabit Networking was accepted in June 1998 and ratified as IEEE 802.3z. This standard uses considers an optical cable for signal transmission. One year later a new standard for Gigabit Ethernet over unshielded twisted pair of the 5th category was certified under the name 802.3ab. Nowadays, there are a couple of younger and older studies about Gigabit Ethernet technology and performance. This Meta Analysis is intended to put the main results altogether into one document suitable for a proper choice of gigabit networking equipment for cluster computers.
214

[en] CATV / GIGABIT ETHERNET / DWDM : NEW TECHNICAL AND ECONOMIC ALTERMATIVES TO THE LAST MILE / [pt] CATV/GIGABIT ETHERNET/DWDM: NOVAS ALTERNATIVAS TÉCNICAS E ECONÔMICAS PARA A ÚLTIMA MILHA

13 August 2002 (has links)
[pt] CATV / Gigabit Ethernet / DWDM : Novas Alternativas Técnicas e Econômicas para a Última Milha tem como objetivo descrever a ativação de novas funcionalidades de uma rede de distribuição de CATV associada à distribuição de dados em faixa larga. A utilização da tecnologia DWDM no domínio óptico, associada a novas topologias de distribuição em cabo coaxial e ao padrão Gigabit Ethernet, permite a obtenção de uma nova concepção em rede de telecomunicações, onde os serviços tradicionais de distribuição analógica são inteiramente preservados. As vantagens desta solução residem na obtenção de uma rede de muito alta velocidade, ideal para aplicações Internet de segunda geração e em um dramático aumento do retorno econômico nas redes CATV já instaladas. / [en] CATV / Gigabit Ethernet / DWDM : New Technical and Economic Altermatives to the Last Mile is aiming at describing the activation of a new family of functionalities applicable to a CATV distribution network together with a delivery of broadband data. Optical domain DWDM technology is used, associated with new coaxial cable distribution topologies and the Gigabit Ethernet standard, allowing for a new telecommunications network concept, where the traditional analogical distribution services are totally preserved. The above proposed solution presents two advantages. The first is such that a very high-speed data network becomes available. This last, is an ideal outfit for second generation Internet. The second advantage is that the obtained data network provides for economic revenues by far greater than those of the traditional CATV networks.
215

Energy Consumption of In-Vehicle Communication in Electric Vehicles : A comparison between CAN, Ethernet and EEE / Energikonsumtion vid intern kommunikation i elbilar : En jämförelse mellan CAN, Ethernet och EEE

French, Kimberley January 2019 (has links)
As a step towards decreasing the greenhouse gas emissions caused by the transport sector, electrical vehicles (EVs) have become more and more popular. Two major problem areas the EV industry is currently facing are range limitations, i.e. being restricted by the capacity of the battery, as well as a demand for higher bandwidth as the in-vehicle communication increases. In this thesis, an attempt is made to address these problem areas by examining the energy consumption required by Controller Area Network (CAN) and Ethernet. In addition, the effects of Energy-Efficient Ethernet (EEE) are reviewed. The protocols are examined by performing a theoretical analysis over CAN, Ethernet and EEE, physical tests over CAN and Ethernet, as well as simulations of EEE. The results show that Ethernet requires 2.5 to four times more energy than CAN in theory, and 4.5 to six times more based on physical measurements. The energy consumption of EEE depends on usage, ranging from energy levels of 40 \% less than CAN when idle, and up to equal amounts as regular Ethernet at high utilisation. By taking full advantage of the traits of Time-Sensitive Networking, EEE has the potential of significantly decreasing the amount of energy consumed compared to standard Ethernet while still providing a much higher bandwidth than CAN, at the cost of introducing short delays. This thesis provides insight into the behaviour of a transmitter for each of the three protocols, discusses the energy implications of replacing CAN with Ethernet and highlights the importance of understanding how to use Ethernet and EEE efficiently.
216

Network Implementation with TCP Protocol : A server on FPGA handling multiple connections / Nätverks implementering med TCP protokoll : En server på FPGA som hanterar flera anslutningar

Li, Ruobing January 2022 (has links)
The growing number of players in Massively Multiplayer Online games puts a heavy load on the network infrastructure and the general-purpose CPU of the game servers. A game server’s network stack processing needs equal treatment to the game-related processing ability. It is a fact that the networkcommunication tasks on the CPU reach the same order of magnitude as the game-related tasks, and the computing capability of the CPU can be a factor that limits the maximum number of players. Therefore, CPU offloading is becoming vital. FPGAs play an essential role in dedicated computation and network communication due to their superiority in flexibility and computation-oriented efficiency. Thus, an FPGA can be a good hardware platform to implement a network stack to replace the CPU in processing the network computations. However, most commercial and open-source network stack IPs support only one or few connections. This thesis project explores a network server on FPGA, implemented in RTL, that can handle multiple connections, specialized in the TCP protocol. The design in this project adds a cached memory hierarchy that provides a filter against port numbers of multiple connections from the same application and an Application Layer Controller, based on an open-source Ethernet, to increase the number of TCP connections further. A proof of concept was built, and its performance was tested. As a result, the TCP server on the FPGA was designed to handle a maximum of 40 configurable connections, but only 25 connections could be maintained during operation due to operational latency constraints. This FPGA server solution provides a latency of 1 ms in LAN. The babbling idiot and out-of-order packet transfer tests from clientswere also performed to guarantee robustness. During testing, poor performance in Packet Loss and Packet Error Handling was noted. In the future, this issue needs to be addressed. In addition, further investigations of methods for expanding the cache need to be done to allow handling more clients. / Det växande antalet spelare i Massively Multiplayer Online-spel belastar nätverksinfrastrukturen och spelservrarnas CPU:er. En spelservers förmåga att bearbeta nätverksstacken måste behandlas lika med den spelrelaterade bearbetningsförmågan. Det är ett faktum att nätverkskommunikationsuppgifterna på processorn når samma storleksordning som de spelrelaterade uppgifterna, och processorns beräkningsförmåga kan vara en faktor som begränsar det maximala antalet spelare. Därför blir avlastning av CPU-viktig. FPGA:er spelar en viktig roll i dedikerad beräkning och nätverkskommunikation på grund av dess överlägsenhet vad gäller flexibilitet och beräkningsorienterad effektivitet. Således kan en FPGA vara en bra hårdvaruplattform för att implementera en nätverksstack, för att ersätta CPU:n vid bearbetning av nätverksberäkningsarna. Men, de flesta kommersiella och öppna källkodsnätverksstack- IP:er stöder dock bara en eller ett fåtal anslutningar. Detta examensarbete utforskar en nätverksserver på FPGA, implementerad mha RTL, som kan hantera flera anslutningar, specialiserad på TCP-protokollet. Designen i detta projekt lägger till en cachad minneshierarki som ger ett filter mot portnummer för flera anslutningar från samma applikation och en Application Layer Controller, baserad på öppen källkod för Ethernet, för att öka antalet TCP-anslutningar ytterligare. Ett proof of concept byggdes och dess prestanda testades. Som ett resultat designades TCP-servern på FPGA:n att kunna hantera maximalt 40 konfigurerbara anslutningar, men endast 25 anslutningar kunde bibehållas under drift på grund av driftsfördröjningar. Denna FPGA-serverlösning ger en latens på 1 ms i LAN. Tester inkluderande den babblande idioten och out-of-order paketöverföring från klienter utfördes också för att garantera robusthet. Under testningen noterades dålig prestanda i paketförlust och paketfelshantering. I framtiden måste denna fråga åtgärdas. Dessutom behöver ytterligare undersökningar av metoder för att utöka cachen göras för att kunna hantera fler klienter.
217

Modern Electrical/Electronic Infrastructure for Commercial Trucks : Generic Input/Output nodes for sensors and actuators in Commercial Trucks

Tomar, Abhineet Singh January 2017 (has links)
The presence of electrical and electronic circuits in commercial trucks has increased at a very fast rate during recent decades. With advancements in embedded systems and the introduction of electric controls in the automotive industry, the design of complex electric systems for the vehicles has become one of the major design challenges. In the commercial truck industry, the development cycles are almost a decade long. Therefore, it is a big challenge to introduce a new architecture to accommodate the modern automotive technologies in the upcoming generation of trucks. Currently, the commercial truck industry relies highly on a federated electrical/electronic (E/E) architecture. In this architecture, Electronic Control Units (ECU) are responsible for computation and Input/Output operations. These ECUs are clustered into different domains based on their respective functions. However, these domains are not isolated from each other. These modules communicate with each other using a vehicular network, which is typically a controller area network in the current trucks. In the automotive industry, automation is increasing at a fast pace. As the level of automation increases, the need for high computation also increases, which increases the overall costs. This study aims to address this problem by introducing an integrated E/E architecture where all the computational power is concentrated at one place (or perhaps two or three places to allow for redundancy). This study proposes to introduce a lowcost replacement for the current ECUs with more limited computational power but with generic input/output interfaces. This thesis provides the reader with some background of the current E/E architecture of commercial trucks and introduces the reader to ECUs. Additionally, the relevant network architectures and protocols are explained. A potential solution, based upon the centralized computation based E/E architecture and its implementation are discussed followed by a detailed analysis of the replacements for ECUs. The result of this analysis, if adopted, should result in a reduction of manufacturing and design costs, as well as make the production and maintenance process easier. Moreover, this should also have environmental benefits by reducing fuel consumption. / Förekomsten av elektronik och elektriska kretsar I kommersiella lastbilar has ökat i en väldigt snabb takt under de senaste decennierna. Med framsteg inom inbyggda system och introduktionen av elektroniska styrsystem i fordonsindustrin så har komplexa elektroniska system blivit en av de största designutmaningarna. I den kommersiella lastbilsindustrin där utvecklingscyklerna är nästan ett decennium, är det en stor utmaning att introducera ny arkitektur som tillgodoser all den nya teknologin som införlivas i fordonet. För närvarande så förlitar sig den kommersiella lastbilsindustrin mycket på en federated elektrisk/elektronisk (E/E) arkitektur. I denna arkitektur är elektroniska styrenheter (ECU) ansvariga för beräkningar och I/O (Input/Output) operationer. Dessa ECU:er är samlade i olika domäner baserade på dess funktioner. Domänerna är dock inte isolerade från varandra. De här modulerna kommunicerar därför med varandra med hjälp av ett fordonsnätverk, typiskt en CAN (Controller Area Network) i nuvarande lastbilar. I fordonsindustrin ökar automatiseringen i en snabb fart. I takt med att automatiseringen ökar så ökar även behovet av snabba och energiintensiva beräkningar, vilket i sin tur ökar den totala kostnaden. Denna studie har som mål att adressera det här problemet genom att introducera en integrated E/E arkitektur där all beräkningskraft är koncentrerad till en plats (eller två eller tre platser för att tillåta överskott). Den här studien föreslår att introducera en ersättning av nuvarande ECU:er till en låg kostnad, med lägre beräkningskraft och generiska I/O gränssnitt. Studien föreslår också ersättningar av nuvarande fordonsnätverk. Den här uppsatsen förser läsaren med viss bakgrund till den nuvarande E/E arkitekturen för kommersiella lastbilar och introducerar läsaren till ECU:er. Dessutom förklaras de relevanta nätverksarkitekturerna och protokollen. En potentiell lösning som baseras på den integrated E/E arkitekturen och dess implementering diskuteras med fokus på en detaljerad analys av ersättningarna till ECU:er. Resultatet av den här analysen skulle, om den adopteras, medföra minskning av tillverknings- och designkostnader samt leda till en förenkling av produktion och underhåll. Utöver det så bör det även ha miljöfördelar genom minskad bränsleförbrukning.
218

Analysis of Data Center Network Convergence Technologies

LeBlanc, Robert-Lee Daniel 01 July 2014 (has links) (PDF)
The networks in traditional data centers have remained unchanged for decades and have grown large, complex and costly. Many data centers have a general purpose Ethernet network and one or more additional specialized networks for storage or high performance low latency applications. Network convergence promises to lower the cost and complexity of the data center network by virtualizing the different networks onto a single wire. There is little evidence, aside from vendors' claims, that validate network convergence actually achieves these goals. This work defines a framework for creating a series of unbiased tests to validate converged technologies and compare them to traditional configurations. A case study involving two different network converged technologies was developed to validate the defined methodology and framework. The study also shows that these two technologies do indeed perform similarly to non-virtualized network, reduce costs, cabling, power consumption and are easy to operate.
219

Combining proprietary real-time Ethernet protocols with Time-Sensitive Networking for avionics : A simulation study in OMNeT++ with INET 4.4 / Kombinering av proprietära Ethernet-baserade realtidsprotokoll med Time-Sensitive Networking i flygplan : En simulerad studie i OMNeT++ med INET 4.4

Ekstedt Karpers, Fredrik January 2023 (has links)
Robust real-time communication is crucial in many safety-critical systems, such as air-crafts. One example of real-time communication within an aircraft is the Ethernet-based protocol called Proprietary Real-Time Ethernet (PRTE), used for sensor data and other hard real-time information exchange. Meanwhile Time Sensitive Networking (TSN) is an emerging group of standards being developed by IEEE, which extends standard Ethernet with real-time capabilities. This thesis investigates the possibility of augmenting a Proprietary Real-Time Ethernet (PRTE) network with TSN functionality, in order to allow for additional, less safety-critical, traffic classes on the same network infrastructure while ensuring real-time correctness of PRTE. A software simulation method through the OMNeT++ 6.0 and INET 4.4 frameworks is used to create and evaluate a small model network. Realistic PRTE traffic is modelled and generated with the help of an XML file with an incomplete PRTE schedule. The same PRTE schedule file is used to calculate an 802.1Qbv schedule for protective TSN windows, used to prevent the PRTE traffic from interference. Additional traffic classes in the form of best-effort traffic are introduced to the network, and multiple network traffic scenarios are considered to evaluate the performance of the network. Both the performance of the PRTE traffic and the non-real-time critical best-effort Ethernet traffic is assessed. The TSN features successfully protect the time-sensitive traffic from interference while inducing a negligible latency increase by introducing the 802.1Q header required by TSN. The best-effort traffic throughput is lowered by a small amount, which is expected as the scheduled traffic reserves bandwidth. The worst-case end-to-end latency of the best-effort traffic is slightly increased across the board, but remains fairly similar to the baseline scenario without TSN windows. Overall, the results are promising and prove that the method can guarantee both PRTE and best-effort performance with minor performance loss. / Robust realtidskommunikation är oumbärligt i många säkerhetskritiska system, som till exempel flygplan. Ett protokoll för realtidskommunikation inom flygplan är det Ethernet-baserade protokollet Proprietary Real-Time Ethernet (PRTE) som används för att skicka bland annat sensordata och annan realtidsinformation. Ett annat exempel är Time Sensitive Networking (TSN), som är en framväxande samling av standarder som utvecklas av IEEE. Time Sensitive Networking (TSN) utökar standard-Ethernet och introducerar realtidsfunktionalitet. Denna rapport undersöker möjligheten att utöka funktionaliteten i Proprietary Real-Time Ethernet (PRTE)-nätverk med TSN-funktionalitet och på så sätt tillåta lägre tidskritiska trafikklasser att kommunicera på samma nätverk, utan att kompromissa på realtids-korrektheten i Proprietary Real-Time Ethernet (PRTE). Mjukvarusimulering med OMNeT++ 6.0 och INET 4.4 används för att skapa och utvärdera små modellnätverk. Realistisk PRTE-trafik modelleras och genereras med hjälp av en XML-fil som innehåller ett ofullständigt PRTEschema. Samma schema-fil används för att generera ett schema med skyddande TSN-fönster enligt 802.1Qbv-standarden. Dessa fönster används för att skydda PRTE-trafiken från lägre prioriterad trafik, och tillåter då så kallad Best Efforttrafik mellan tidskritiska fönster. Olika mönster av Best Effort-trafik genereras och dess effekt på nätverket utvärderas. Både prestandan av PRTE och Best Effort-trafiken tas i beaktning. TSN-funktionerna lyckas med att skydda den tidskritiska trafiken, och leder endast till väldigt låga latens-ökningar på grund av att 802.1Q-headers introduceras. Överföringshastigheten för Best Effort-trafik minskade något, vilket var förväntat då de schemalagda TSN-fönstren tar upp bandbredd. Värstafallsfördröjningen i Best Effort-trafiken ökade något över lag, men höll sig förhållandevis nära grundscenariot utan TSN-fönster. Sammantaget är resultaten lovande och bevisar att metoden kan garantera leverans av PRTE-paket samtidigt som Best Effort-trafik skickas med små prestandaförluster.
220

Soft Real-Time Switched Ethernet: Best-Effort Packet Scheduling Algorithm, Implementation, and Feasibility Analysis

Wang, Jinggang 10 October 2002 (has links)
In this thesis, we present a MAC-layer packet scheduling algorithm, called Best-effort Packet Scheduling Algorithm(BPA), for real-time switched Ethernet networks. BPA considers a message model where application messages have trans-node timeliness requirements that are specified using Jensen's benefit functions. The algorithm seeks to maximize aggregate message benefit by allowing message packets to inherit benefit functions of their parent messages and scheduling packets to maximize aggregate packet-level benefit. Since the packet scheduling problem is NP-hard, BPA heuristically computes schedules with a worst-case cost of O(n^2), faster than the O(n^3) cost of the best known Chen and Muhlethaler's Algorithm(CMA) for the same problem. Our simulation studies show that BPA performs the same or significantly better than CMA. We also construct a real-time switched Ethernet by prototyping an Ethernet switch using a Personal Computer(PC) and implementing BPA in the network protocol stack of the Linux kernel for packet scheduling. Our actual performance measurements of BPA using the network implementation reveal the effectiveness of the algorithm. Finally, we derive timeliness feasibility conditions of real-time switched Ethernet systems that use the BPA algorithm. The feasibility conditions allow real-time distributed systems to be constructed using BPA, with guaranteed soft timeliness. / Master of Science

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