Dissertations / Theses on the topic 'Software router'
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Svantesson, Björn. "Software Defined Networking : Virtual Router Performance." Thesis, Högskolan i Skövde, Institutionen för informationsteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-13417.
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Virtualization is becoming more and more popular since the hardware that is available today often has theability to run more than just a single machine. The hardware is too powerful in relation to the requirementsof the software that is supposed to run on the hardware, making it inefficient to run too little software ontoo powerful of machines. With virtualization, the ability exists to run a lot of different software on thesame hardware, thereby increasing the efficiency of hardware usage.Virtualization doesn't stop at just virtualizing operating systems or commodity software, but can also beused to virtualize networking components. These networking components include everything from routersto switches and are possible to set up on any kind of virtulized system.When discussing virtualization of networking components, the experssion “Software Defined Networking”is hard to miss. Software Defined Networking is a definition that contains all of these virtualized networkingcomponents and is the expression that should be used when researching further into this subject. There'san increasing interest in these virtualized networking components now in relation to just a few years ago.This is due to company networking becoming much more complex now in relation to the complexity thatcould be found in a network a few years back. More services need to be up inside of the network and a lotof people believe that Software Defined Networking can help in this regard.This thesis aim is to try to find out what kind of differences there are between multiple different softwarerouters. Finding out things like, which one of the routers that offer the highest network speed for the leastamount of hardware cost, are the kind of things that this thesis will be focused on. It will also look at somedifferent aspects of performance that the routers offer in relation to one another in order to try toestablish if there exists any kind of “best” router in multiple different areas.The idea is to build up a virtualized network that somewhat relates to how a normal network looks insmaller companies today. This network will then be used for different types of testing while having thesoftware based router placed in the middle and having it take care of routing between different local virtualnetworks. All of the routers will be placed on the same server and their configuration will be very basicwhile also making sure that each of the routers get access to the same amount of hardware.After initial testing, all routers that perform bad will be opted out for additional testing. This is done tomake sure that there's no unnecessary testing done on routers that seem to not be able to keep up withthe other ones. The results from these tests will be compared to the results of a hardware router with thesame kind of tests used with it in the middle in relation to the tests the software routers had to go through.The results from the testing were fairly surprising, only having one single router being eliminated early onas the remaining ones continued to “battle” one another with more tests. These tests were compared tothe results of a hardware router and the results here were also quite surprising with a much betterperformance in many different areas from the software routers perspective.
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Tanyingyong, Voravit. "Performance and Reliability in Open Router Platforms for Software-Defined Networking." Licentiate thesis, KTH, Network Systems Laboratory (NS Lab), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-144285.
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The unprecedented growth of the Internet has brought about such an enormous impact on our daily life that it is regarded as indispensable in modern era. At the same time, the underlying Internet architecture is still underpinned by principles designed several decades ago. Although IP networking has been proven very successful, it has been considered as the cause to network ossification creating barriers to entry for new network innovations. To support new demands and requirements of the current and the future Internet, solutions for new and improved Internet architectures should be sought. Software-defined networking (SDN), a new modularized network architecture that separates the control plane from the data plane, has emerged as a promising candidate for the future Internet. SDN can be described as flow-based networking, which provides finer granularity while maintaining backward compatibility with traditional IP networking. In this work, our goal is to investigate how to incorporate flow-based networking into open router platforms in an SDN context. We investigate performance and reliability aspects related to SDN data plane operation in software on open source PC-based routers. Our research methodology is based on design, implementation, and experimental evaluation. The experimental platform consists of PC-based routers running open source software in combination with commodity-off-the-shelf (COTS) hardware components. When it comes to performance aspects, we demonstrate that by offloading the lookup from a CPU to a network interface card, the overall performance is improved significantly. For enhanced reliability, we investigate bidirectional forwarding detection (BFD) as a component to realize redundancy with fast failover. We demonstrate that BFD becomes unreliable under high traffic load and propose a solution to this problem by allocating dedicated system resources for BFD control messages. In line with this solution, we extend our architecture for next-generation PC-based routers with OpenFlow support by devising a strategy to efficiently map packet forwarding and application processing tasks onto the multi-core architecture on the PC-based router. This extension would make it possible to integrate BFD effectively into the router platform. Our work demonstrates the potentials of open router platforms for SDN. Our prototypes offer not only high performance with good reliability but also flexibility to adopt new software extensions. Such platforms will play a vital role in advancing towards the future Internet.QC 20140416
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Hunt, David. "An implementation of a cross-platform wireless router operating system." [Denver, Colo.] : Regis University, 2007. http://165.236.235.140/lib/DHunt2007.pdf.
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Forgione, Alessandro. "Openflow e software-defined networking: l'evoluzione della rete programmabile." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7919/.
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Il paradigma “Software-Defined Networking” (SDN) ha suscitato recentemente interesse grazie allo sviluppo e all'implementazione di uno standard tecnologico come OpenFlow. Con il modello SDN viene proposta una rete programmabile tramite la separazione dell’unità di controllo e l'unità di instradamento, rendendo quindi i nodi di rete (come ad es. router o switch) esclusivamente hardware che inoltra pacchetti di dati secondo le regole dettate dal controller. OpenFlow rappresenta lo standard dominante nella tecnologia SDN in grado di far comunicare l'unità controller e l'hardware di uno o più nodi di rete. L'utilizzo di OpenFlow consente maggiore dinamicità e agevolazione nella personalizzazione della rete attraverso un'interfaccia utente, includendo svariate funzioni quali la modifica e l’automatizzazione delle regole di instradamento, la creazione di una rete virtuale dotata di nodi logici o la possibilità di monitorare il traffico accrescendo la sicurezza della propria rete.
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Granberg, Tony. "Mjukvara för träning av routersyntax." Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-107736.
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Det här arbetet handlar om en mjukvara vars mål är att tillhandahålla syntaxträning inom routeradministration inriktad mot målgruppen studenter. Mjukvaran har programmerats från grunden i programmeringsspråket Python och är menad att erbjuda ett simplistiskt användargränsnitt. Programmeringen har resulterat i ett program som döpts till Routersyntax och består av två delar: ett klientprogram och ett serverprogram. Både klientprogrammet och serverprogrammet går att installera och köra i flera olika operativsystemmiljöer, med främsta fokus på Windows, Ubuntu Linux och OS X. Det är simplistiskt utformat, enkelt att installera och köra, samt gratis att använda för studenter. Förhoppningen är att användaren med hjälp av syntaxträningsmjukvaran ska få en chans att träna sina färdigheter i att skriva routerkommandon för användning av studenter i universitetskurser.This report explains the implementation and purpose for the computer software called Routersyntax that aims to assist students in exercising router command syntax. Written in Python, the software uses a simplistic command line-driven user interface, designed specifically for routing administration training. The software is divided into two parts: a client and a server. Using the router syntax software, users get an opportunity to try to improve their skills in administering router hardware by exercising router command input in an environment which is free to use for students. The aim is for the software to require nothing but Python and a Python-compatible operating system to run. It supports Windows, Ubuntu Linux and OS X out of the box.
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Luštický, Josef. "40GbE směrovač pro operační systém GNU/Linux." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2015. http://www.nusl.cz/ntk/nusl-234945.
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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.
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Shahzad, Syed Amir. "Route aggregation in Software-defined Networks." Thesis, KTH, Radio Systems Laboratory (RS Lab), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-123977.
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Software-defined Networking (SDN) is an emerging trend in communication networks that facilitates decoupling the control and data plane of multilayer switches. A logically centralized controller hosted on a server configures the forwarding tables (flow tables) of switches in order to route the various data flows. To implement SDN, OpenFlow technology has been adopted by packet switching vendors as it provides increased flexibility for the control and management of a packet switched domain. OpenFlow technology provides flow based switching that is controlled by a network management control application running in an OpenFlow controller. In this thesis work we investigate how an OpenFlow Controller communicates with a legacy network via the OSPF routing protocol, how the size of the OpenFlow network effects the resources (memory and CPU) of a legacy router to whom the controller communicates. Also we examine bandwidth utilization of the link (between the OpenFlow network and legacy router). The main goal of this thesis is to find methods to reduce the consumption of resources of a legacy router. This study shows that the size of OpenFlow network directly affects the usage of the link’s bandwidth, and the memory and CPU usage of a legacy router. Aggregated information from the OpenFlow controller which is sent towards the legacy router can reduce the utilization of these resources. Finally we proposed several algorithms and design models that can be implemented for route aggregation in Software-defined Networks. Implementation of the solutions suggested in this thesis will allow automatic route aggregation in SDN. ISPs deploying SDN architecture could benefit from the proposed design models and route aggregation solution.Software-definierade nätverk (SDN) är en framväxande trend i kommunikationsnät som underlättar frikoppling kontroll och uppgifter plan flerskiktade switchar. Ett logiskt centraliserad styrenhet på en server konfigurerar vidarebefordran tabeller (flödestabeller) av växlar för att dirigera de olika dataflöden. För att genomföra SDN har OpenFlow teknik har antagits av paketförmedlande leverantörer eftersom det ger ökad flexibilitet för kontroll och förvaltning av en påslagen paket domän. OpenFlow teknik ger flöde baserad omkoppling som styrs av ett nätverk ledningens kontroll som körs i en OpenFlow controller. I detta examensarbete undersöker vi hur en OpenFlow Controller kommunicerar med ett äldre nätverk via OSPF routing protokoll, hur storleken på OpenFlow nätverkseffekter de resurser (minne och CPU) av en äldre router till vilken styrenheten kommunicerar. Också vi undersöker bandbreddsutnyttjandet av sambandet (mellan OpenFlow nätverket och äldre router). Det huvudsakliga målet med detta examensarbete är att hitta metoder för att minska konsumtionen av resurser från en äldre router. Denna studie visar att storleken på OpenFlow nätverk direkt påverkar användningen av länkens bandbredd och minne och CPU-användning av en äldre router. Samlad information från OpenFlow styrenhet som sändes mot äldre router kan minska utnyttjandet av dessa resurser. Slutligen föreslog vi flera algoritmer och modeller konstruktion som kan genomföras för route aggregation i Software Defined-nätverk. Genomförandet av de lösningar som föreslås i denna avhandling kommer att möjliggöra automatisk route aggregation i SDN. Internetleverantörer distribuerar SDN arkitektur kunde dra nytta av den föreslagna utformningen modeller och route aggregation lösning.
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Egi, Norbert. "Software virtual routers on commodity hardware architectures." Thesis, Lancaster University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.539674.
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Lepe, Aldama Oscar Iván. "Modeling TCP/IP software implementation performance and its application for software routers." Doctoral thesis, Universitat Politècnica de Catalunya, 2002. http://hdl.handle.net/10803/5975.
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Existen numerosos trabajos que estudian o tratan la realización software de los protocolos de comunicaciones para el acceso a la Internet-TCP/IP. Sin embargo, no conocemos ninguno que modele de forma general y precisa la ejecución de este software.La presente tesis aporta una caracterización detallada de la ejecución de la realización software de los mencionados protocolos sobre un computador personal y bajo un sistema operativo UNIX. Esta caracterización muestra cómo varía el rendimiento del sistema en función de la velocidad de operación de la CPU, las características del subsistema de memoria, el tamaño de los paquetes y otras variables de importancia para la remisión, autenticación y cifrado de paquetes IP.
En otros trabajos se proponen adecuaciones o extensiones a la realización software de los mencionados protocolos que permiten que un software router provea de comunicaciones con diversos niveles asegurados de calidad mediante el uso de mecanismos de planificación para la unidad central de procesamiento. Sin embargo, en dichos trabajos no se contempla la planificación del uso del bus de entrada/salida.
Los resultados derivados de nuestro modelo demuestran que, para sistemas que usan CPUs con frecuencias de reloj superiores a 1 GHz, la planificación conjunta de la CPU y el bus de entrada salida es indispensable para la provisión de comunicaciones con diversos niveles asegurados de calidad. Dichas frecuencias de reloj son comunes en los sistemas comerciales actuales, por lo que consideramos que es un problema de gran interés. En la tesis proponemos un mecanismo que consigue garantías de utilización del bus de entrada/salida mediante la modificación de los drivers de los interfaces de red.
Three are the main contributions of this work. In no particular order:
" A detailed performance study of the software implementation of the TCP/IP protocols suite, when executed as part of the kernel of a BSD operating system over generic PC hardware.
" A validated queuing network model of the studied system, solved by computer simulation.
" An I/O bus utilization guard mechanism for improving the performance of software routers supporting QoS mechanisms and built upon PC hardware and software.
This document presents our experiences building a performance model of a PC-based software router. The resulting model is an open multiclass priority network of queues that we solved by simulation. While the model is not particularly novel from the system modeling point of view, in our opinion, it is an interesting result to show that such a model can estimate, with high accuracy, not just average performance-numbers but the complete probability distribution function of packet latency, allowing performance analysis at several levels of detail. The validity and accuracy of the multiclass model has been established by contrasting its packet latency predictions in both, time and probability spaces. Moreover, we introduced into the validation analysis the predictions of a router's single queue model. We did this for quantitatively assessing the advantages of the more complex multiclass model with respect to the simpler and widely used but not so accurate, as here shown, single queue model, under the considered scenario that the router's CPU is the system bottleneck and not the communications links. The single queue model was also solved by simulation.
Besides, this document addresses the problem of resource sharing in PC-based software routers supporting QoS mechanisms. Others have put forward solutions that are focused on suitably distributing the workload of the CPU-see this chapter's section on "related work". However, the increase in CPU speed in relation to that of the I/O bus-as here shown-means attention must be paid to the effect the limitations imposed by this bus on the system's overall performance. We propose a mechanism that jointly controls both I/O bus and CPU operation. This mechanism involves changes to the operating system kernel code and assumes the existence of certain network interface card's functions, although it does not require changes to the PC hardware. A performance study is shown that provides insight into the problem and helps to evaluate both the effectiveness of our approach, and several software router design trade-offs.
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Jakobson, Fredrik. "Open source routing software : A comparative study of open source software routers." Thesis, Högskolan i Skövde, Institutionen för informationsteknologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-9520.
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As the performance of PCs is increasing it is of great interest to use these cheap devices as routers,which traditionally consisted of more expensive and customized hardware for that purpose. Thesoftware was also traditionally proprietary and thereby costly, but as the open source communityhas grown there have been development of open source solutions that can perform the task ofacting as a router. However as there are so many solutions out there, it can be hard for the potentialusers to choose which particular solution to use, without having to put in too much work intogetting a fully functional router solution. This study achieved this purpose by benchmarking themost popular open source software routers, in terms of performance and scalability as well asproviding a brief analysis of their basic security features. The routers that were studied wasClearOS, Untangle NG Firewall and IPFire, and after the study was complete IPFire was consideredthe superior with ClearOS as the second and Untangle as third and last.
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Prado, Alexandre Barcellos. "Auto-configuration of Cisco routers with application software." Thesis, Monterey, California. Naval Postgraduate School, 2003. http://hdl.handle.net/10945/6285.
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Approved for public release, distribution unlimitedThe context of this research is to facilitate the control of routers with the Server and Agent based Active Network Management (SAAM), to optimize allocation of network resources, and to satisfy user Quality of Service (QoS) requirements. The SAAM network determines the Quality of Service parameters based on current network conditions and user requirements. These parameters are dynamic, so they must be uploaded into the Cisco routers to take effect. The focus is on determining the most efficient way of communicating between the Cisco routers and the SAAM system. This is accomplished by several key components of the proxy-based solution as the first step for integrating with a legacy network. This thesis develops methods and application software to automatically update the configurations of Cisco routers based on the current network condition. These methods are required by any solution that resolves to upgrade the existing legacy network to provide QoS without expensive equipment replacement. As a result users are provided with a network they can expect to function properly.
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Prado, Alexandre B. "Auto-configuration of Cisco routers with application software /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03sep%5FPrado.pdf.
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Herbert, Alan. "Towards large scale software based network routing simulation." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1017931.
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Software based routing simulators suffer from large simulation host requirements and are prone to slow downs because of resource limitations, as well as context switching due to user space to kernel space requests. Furthermore, hardware based simulations do not scale with the passing of time as their available resources are set at the time of manufacture. This research aims to provide a software based, scalable solution to network simulation. It aims to achieve this by a Linux kernel-based solution, through insertion of a custom kernel module. This will reduce the number of context switches by eliminating the user space context requirement, and serve to be highly compatible with any host that can run the Linux kernel. Through careful consideration in data structure choice and software component design, this routing simulator achieved results of over 7 Gbps of throughput over multiple simulated node hops on consumer hardware. Alongside this throughput, this routing simulator also brings to light scalability and the ability to instantiate and simulate networks in excess of 1 million routing nodes within 1 GB of system memory
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Bassey, Ukemeobong Okon. "On iBGP Multicasting in Software Defined Networks." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36871.
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In the Internet today, learnt prefixes are forwarded within autonomous systems (ASs) over internal Border Gateway Protocol (iBGP) sessions. Existing schemes for iBGP routing include the full-mesh (FM) solution, route reflection (RR) solution and confederation. Optimal prefix routing and route diversity are the main strength of the FM solution. However, it is rarely employed in a large networks due to its deficiency in aspects including scalability and large Routing Information Base (RIB) size requirement of routers. This is due to the fact that routers in this topology are required to peer with every other router within the AS. To combat these challenges, the RR scheme provides solution for scalability by decreasing the iBGP sessions requirement. Notwithstanding, the RR solution has its own challenges which includes reduced route diversity, introduction of divergence and forwarding anomalies. Also, the FM optimality may be lost since the Route Reflectors are responsible for reflecting the learnt prefixes to their corresponding clients based on its partial view of the network. The concept of Software Defined Networking (SDN) entails decoupling of the control plane from the forwarding plane such that the control plane is logically centralized benefiting from an overall knowledge of the network for decision making.
In this work, we propose a solution based on multicasting which employs relay nodes in the iBGP message dissemination. Our solution brings session management scalability and minimization of duplicate prefix announcement through elimination of peer sessions deemed unnecessary. SDN controller is employed to configure and coordinate the multicast tree.
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Meacham, Richard J. "High-level design routes for digital systems." Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298949.
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Janura, Dominik. "Návrh softwaru sloužícího k mapování topologie sítě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220628.
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This thesis addresses the issues of network topology mapping, where the network consists of multiple Cisco devices. It includes theoretical knowledge in this field and closely describes possible solutions to this problem. It explains the process of design and implementation of this kind of network mapping software by chosen means. Correct function of the created application is tested on a virtual network.
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Wagner, Laurent. "MINESTIS, the route to resource estimates." Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2015. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-181676.
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Minestis software allows geological domain modeling and resource estimation through an efficient and simplified geostatistics-based workflow. It has been designed for all those, geologists, mining engineers or auditors, for whom quick production of quality models is at the heart of their concerns.
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Söderberg, Fredrik. "Route Planning for Heavy Vehicles on Real World Maps." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-411686.
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Fast route planning for a standard car is well explored, lots of research, and many algorithms exist. For trucks or other heavy vehicles, the available research and quick algorithm alternatives dwindle. This thesis focuses on available alternatives for trucks and other vehicles with attributes hindering them from traversing parts of the road network. Attributes like height are one among many, which can hinder a vehicle on its path. These attributes can vary greatly and is the reason why known solutions can’t be applied. Many well-known solutions rely partially on precalculated data regarding the shortest path for its performance. Precalculating for all possible combinations of attributes is not practical due to the number of possible configurations and the amount of computing needed for each one. The implemented solution is derived from multiple existing solutions and was evaluated on a graph representing Sweden’s road network. The solution is sufficiently fast to allow commercial use and allows changes to the road network with nightly updates. The solution is based on trying to predict which roads are more important when searching for the shortest path. With this knowledge, a search for the shortest path can be said to prioritize the before mentioned roads, which results in it finding its goal faster.Snabb ruttplanering för en vanlig personbil är välutforskat med mycket tillgänglig forskning och många existerande algoritmer. För lastbilar och andra tunga fordon minskar den tillgängliga forskningen och alternativa algoritmer kraftigt. Den här avhandlingen fokuserar på alternativen som existerar för lastbilar, samt andra fordon som har egenskaper vilket blockerar dem från att framföras på delar av vägnätverket. Höjd är ett attribut bland flera som kan hindra ett fordon från att ta sig fram. Dessa egenskaper kan variera kraftigt och är orsaken till varför kända lösningar inte går att applicera. Många välkända lösningar förlitar sig på förberäknad data gällande snabbaste möjliga väg för sin prestanda. Att utföra dessa beräkningar för alla möjliga kombinationer av egenskaper är opraktiskt på grund av antalet möjliga konfigurationer och hur mycket som måste räknas ut för varje. Den implementerade lösningen är en kombination av flera existerande lösningar och utvärderades på en graf som representerar det svenska vägnätet. Lösningen är snabb nog för att tillåta bruk inom det kommersiella och den tillåter förändringar i vägnätet med nattliga uppdateringar. Lösningen bygger på att försöka förutsäga vilka vägar i ett vägnät som är viktigare än andra när det gäller att finna den snabbaste vägen. Med hjälp av det kan man sedan styra en sökning så att den prioriterar dessa vägar och därmed hitta sitt mål fortare.
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Abdulai, Jamal-deen. "Probabilistic route discovery for Wireless Mobile Ad Hoc Networks (MANETs)." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/719/.
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Mobile wireless ad hoc networks (MANETs) have become of increasing interest in view of their promise to extend connectivity beyond traditional fixed infrastructure networks. In MANETs, the task of routing is distributed among network nodes which act as both end points and routers in a wireless multi-hop network environment. To discover a route to a specific destination node, existing on-demand routing protocols employ a broadcast scheme referred to as simple flooding whereby a route request packet (RREQ) originating from a source node is blindly disseminated to the rest of the network nodes. This can lead to excessive redundant retransmissions, causing high channel contention and packet collisions in the network, a phenomenon called a broadcast storm. To reduce the deleterious impact of flooding RREQ packets, a number of route discovery algorithms have been suggested over the past few years based on, for example, location, zoning or clustering. Most such approaches however involve considerably increased complexity requiring additional hardware or the maintenance of complex state information. This research argues that such requirements can be largely alleviated without sacrificing performance gains through the use of probabilistic broadcast methods, where an intermediate node rebroadcasts RREQ packets based on some suitable forwarding probability rather than in the traditional deterministic manner. Although several probabilistic broadcast algorithms have been suggested for MANETs in the past, most of these have focused on “pure” broadcast scenarios with relatively little investigation of the performance impact on specific applications such as route discovery. As a consequence, there has been so far very little study of the performance of probabilistic route discovery applied to the well-established MANET routing protocols. In an effort to fill this gap, the first part of this thesis evaluates the performance of the routing protocols Ad hoc On demand Distance Vector (AODV) and Dynamic Source Routing (DSR) augmented with probabilistic route discovery, taking into account parameters such as network density, traffic density and nodal mobility. The results reveal encouraging benefits in overall routing control overhead but also show that network operating conditions have a critical impact on the optimality of the forwarding probabilities. In most existing probabilistic broadcast algorithms, including the one used here for preliminary investigations, each forwarding node is allowed to rebroadcast a received packet with a fixed forwarding probability regardless of its relative location with respect to the locations of the source and destination pairs. However, in a route discovery operation, if the location of the destination node is known, the dissemination of the RREQ packets can be directed towards this location. Motivated by this, the second part of the research proposes a probabilistic route discovery approach that aims to reduce further the routing overhead by limiting the dissemination of the RREQ packets towards the anticipated location of the destination. This approach combines elements of the fixed probabilistic and flooding-based route discovery approaches. The results indicate that in a relatively dense network, these combined effects can reduce the routing overhead very significantly when compared with that of the fixed probabilistic route discovery. Typically in a MANET there are regions of varying node density. Under such conditions, fixed probabilistic route discovery can suffer from a degree of inflexibility, since every node is assigned the same forwarding probability regardless of local conditions. Ideally, the forwarding probability should be high for a node located in a sparse region of the network while relatively lower for a node located in a denser region of the network. As a result, it can be helpful to identify and categorise mobile nodes in the various regions of the network and appropriately adjust their forwarding probabilities. To this end the research examines probabilistic route discovery methods that dynamically adjust the forwarding probability at a node, based on local node density, which is estimated using number of neighbours as a parameter. Results from this study return significantly superior performance measures compared with fixed probabilistic variants. Although the probabilistic route discovery methods suggested above can significantly reduce the routing control overhead without degrading the overall network throughput, there remains the problem of how to select efficiently forwarding probabilities that will optimize the performance of a broadcast under any given conditions. In an attempt to address this issue, the final part of this thesis proposes and evaluates the feasibility of a node estimating its own forwarding probability dynamically based on locally collected information. The technique examined involves each node piggybacking a list of its 1-hop neighbours in its transmitted RREQ packets. Based on this list, relay nodes can determine the number of neighbours that have been already covered by a broadcast and thus compute the forwarding probabilities most suited to individual circumstances.
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Lomba, Ana Cristina Galvão de Oliveira. "Estudo da implementação de um software de optimização de rotas numa empresa portuguesa de distribuição." Master's thesis, Instituto Superior de Economia e Gestão, 2013. http://hdl.handle.net/10400.5/11183.
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Mestrado em Gestão e Estratégia IndustrialO objetivo deste trabalho é avaliar as melhorias do serviço de entregas de uma empresa de distribuição após a implementação de um software de planeamento e otimização de rotas. Nos dias de hoje, a capacidade de reduzir custos e manter a competitividade, tem ganho cada vez mais importância. Assim, a ELPOR, uma empresa de distribuição de material elétrico, decidiu melhorar o seu serviço de entregas e simultaneamente reduzir os custos associados ao transporte implementando um software de planeamento de rotas chamado TourSolver. A partir da comparação do número retornos na rota otimizada e na rota não-otimizada iremos concluir que as rotas otimizadas apresentam geralmente menos retornos que as rotas não otimizadas.
The purpose of this project is to evaluate the improvements in the delivery service of a distribution company after the implementation of a vehicle routing software. Nowadays, the capacity to reduce costs, and improve competitiveness is gaining more importance than ever. So, ELPOR, an electric material wholesaler, decided to improve their deliveries service and simultaneity reduce the transport costs by implementing a vehicle routing software named TourSolver. By comparing the number of returned packages in the optimized and non-optimized route, we will conclude that optimized routes generally have less returned packages than non-optimized routes.
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Venmani, Daniel Philip. "Multi-operator greedy routing based on open routers." Phd thesis, Institut National des Télécommunications, 2014. http://tel.archives-ouvertes.fr/tel-00997721.
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Revolutionary mobile technologies, such as high-speed packet access 3G (HSPA+) and LTE, have significantly increased mobile data rate over the radio link. While most of the world looks at this revolution as a blessing to their day-to-day life, a little-known fact is that these improvements over the radio access link results in demanding tremendous improvements in bandwidth on the backhaul network. Having said this, today's Internet Service Providers (ISPs) and Mobile Network Operators (MNOs) are intemperately impacted as a result of this excessive smartphone usage. The operational costs (OPEX) associated with traditional backhaul methods are rising faster than the revenue generated by the new data services. Building a mobile backhaul network is very different from building a commercial data network. A mobile backhaul network requires (i) QoS-based traffic with strict requirements on delay and jitter (ii) high availability/reliability. While most ISPs and MNOs have promised advantages of redundancy and resilience to guarantee high availability, there is still the specter of failure in today's networks. The problems of network failures in today's networks can be quickly but clearly ascertained. The underlying observation is that ISPs and MNOs are still exposed to rapid fluctuations and/or unpredicted breakdowns in traffic; it goes without saying that even the largest operators can be affected. But what if, these operators could now put in place designs and mechanisms to improve network survivability to avoid such occurrences? What if mobile network operators can come up with low-cost backhaul solutions together with ensuring the required availability and reliability in the networks? With this problem statement in-hand, the overarching theme of this dissertation is within the following scopes: (i) to provide low-cost backhaul solutions; the motivation here being able to build networks without over-provisioning and then to bring-in new resources (link capacity/bandwidth) on occasions of unexpected traffic surges as well as on network failure conditions for particularly ensuring premium services (ii) to provide uninterrupted communications even at times of network failure conditions, but without redundancy. Here a slightly greater emphasis is laid on tackling the 'last-mile' link failures. The scope of this dissertation is therefore to propose, design and model novel network architectures for improving effective network survivability and network capacity, at the same time by eliminating network-wide redundancy, adopted within the context of mobile backhaul networks. Motivated by this, we study the problem of how to share the available resources of a backhaul network among its competitors, with whom a Service Level Agreement (SLA) has been concluded. Thus, we present a systematic study of our proposed solutions focusing on a variety of empirical resource sharing heuristics and optimization frameworks. With this background, our work extends towards a novel fault restoration framework which can cost-effectively provide protection and restoration for the operators, enabling them with a parameterized objective function to choose desired paths based on traffic patterns of their end-customers. We then illustrate the survivability of backhaul networks with reduced amount of physical redundancy, by effectively managing geographically distributed backhaul network equipments which belong to different MNOs using 'logically-centralized' physically-distributed controllers, while meeting strict constraints on network availability and reliability
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Uskay, Selim Onur. "Route Optimization For Solid Waste Transportation Using Parallel Hybrid Genetic Algorithms." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612942/index.pdf.
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The transportation phase of solid waste management is highly critical as it may constitute approximately 60 to 75 percent of the total cost. Therefore, even a small amount of improvement in the collection operation can result in a significant saving in the overall cost. Despite the fact that there exist a considerable amount of studies on Vehicle Routing Problem (VRP), a vast majority of the existing studies are not integrated with GIS and hence they do not consider the path constraints of real road networks for waste collection such as one-way roads and U-Turns. This study involves the development of computer software that optimizes the waste collection routes for solid waste transportation considering the path constraints and road gradients. In this study, two different routing models are proposed. The aim of the first model is to minimize the total distance travelled whereas that of the second model is to minimize the total fuel consumption that depends on the loading conditions of the truck and the road gradient. A comparison is made between these two approaches. It is expected that the two approaches generate routes having different characteristics. The obtained results are satisfactory. The distance optimization model generates routes that are shorter in length whereas the fuel consumption optimization model generates routes that are slightly higher in length but provides waste collection on steeply inclined roads with lower truck load. The resultant routes are demonstrated on a 3D terrain view.
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Dong, Yu Lin. "The formal development of a railway station route management system." Thesis, University of Macau, 1995. http://umaclib3.umac.mo/record=b1636969.
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Kaske, Axel. "Contribution à la détection des bords de route imprécis : implantation sur le robot ROMANE." Vandoeuvre-les-Nancy, INPL, 1997. http://www.theses.fr/1997INPL039N.
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Les deux premiers chapitres de la thèse présentent un état de l'art de la vision artificielle pour la robotique mobile et décrivent le projet de robot ROMANE. La structure matérielle et les logiciels utilisés y sont présentés. La calibration du système de vision est décrite en détail dans le chapitre III. Le cœur de la thèse (chapitre IV et V) est consacré à la présentation de 2 méthodes différentes de détection de bords de route. Toutes les deux sont fondées sur le même modèle de type hyperbolique, mais elle différent par le concept utilisé pour adapter les paramètres du modèle suivant des images de scènes réelles étudiées. La première fait appel à une fonction de vraisemblance pour évaluer l'écart entre le modèle et le système réel. Une recherche aléatoire est mise en œuvre pour trouver le modèle le mieux adapté. La seconde met en œuvre une statistique du 2e ordre (co-occurence) associée à une recherche d'extrema pour adapter les paramètres du modèle aux points extraits de l'image, elle utilise un critère fonde sur le X2. Une série de résultats établis à partir d'images vidéo de scènes réelles permet de valider les approches proposées
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Marcantoni, Giulio. "integrazione di una piattaforma software («ptv route optimizer») a supporto dell’attività di pianificazione dei viaggi del settore chiamato volante. il caso unilog group spa." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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Il lavoro di questa tesi mira ad analizzare alcune delle problematiche derivanti dalla pianificazione dei viaggi e dalla gestione delle volumetrie della merce passante per i magazzini della Società Unilog Group S.p.A. la cui sede risiede ad Anzola dell’Emilia (BO).
Il suo principale obiettivo è quello di introdurre il software di pianificazione PTV Route Optimizer per la creazione automatica dei viaggi per il ritiro e consegne della merce affidata dalla Grade Distribuzione Organizzata ad Unilog. Alla base di questo, si è quindi resa necessaria una approfondita analisi dei processi direttamente o indirettamente correlati a quello di pianificazione in modo da individuare fin da subito sia altre aree di miglioramento slegate all'introduzione del nuovo software sia per effettuare una migliore progettazione del nuovo processo di pianificazione stesso. A questo si è affiancata anche un'attività di analisi delle volumetrie delle merci trasportate dai mezzi della società in modo da poter incrementare la precisione di dati di input del software e quindi anche quella dei risultati stessi in termini di saturazione dei mezzi e numero di questi generati. Sono infine riportati i risultati dei test fatti una volta personalizzato il software alle esigenze dell'azienda e le considerazioni finali sulle criticità da superare per iniziare ad utilizzarlo in produzione
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Hartikka, Alice, and Simon Nordenhög. "Emission Calculation Model for Vehicle Routing Planning : Estimation of emissions from heavy transports and optimization with carbon dioxide equivalents for a route planning software." Thesis, Linköpings universitet, Energisystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-178065.
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The transport sector is a major cause of emissions both in Sweden and globally. This master thesis aims to develop a model for estimating emissions from heavy transport on a specific route. The emissions can be used in a route planning software and help the driver choose a route that contributes to reduced emissions. The methodology was to investigate attributes, like vehicle-related attributes and topography, and their impact on transport emissions. The carbon dioxide, methane and nitrous oxide emissions were converted into carbon dioxide equivalents, which were incorporated as one cost together with a precalculated driving time as a second cost in a multi objective function used for route planning. Different tests were conducted to investigate the accuracy and the usability of the model. First, a validation test was performed, where the optimized routes were analyzed. The test showed that the model was more likely to choose a shorter route in general. The fuel consumption values largely met expectations towards generic values and measurements, that were gathered from research. A second test of the model made use of the driving time combined with the emissions in a multi objective function. In this test, a weighting coefficient was varied and analyzed to understand the possibility to find a value of the coefficient for the best trade-off. The result showed that the model generates different solutions for different coefficients and that it is possible to find a suitable trade-off between the driving time and emissions. Therefore, this study shows that there is a possibility to combine emission with other objectives such as driving time for route optimization. Finally, a sensitivity analysis was performed, where attribute factors and assumptions were varied to see how sensitive they were and, in turn, how much a change would impact the calculated emissions. The result from the sensitivity analysis showed that the changes in topography-attributes had less impact than changes on vehicle-related attributes. In conclusion, this thesis has built a foundation for route planning, based on the environmental aspect, for heavy transports.
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Heathcote, Jonathan David. "Building and operating large-scale SpiNNaker machines." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/building-and-operating-largescale-spinnaker-machines(6151916a-ed71-42e4-97d2-2993a4caf5f6).html.
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SpiNNaker is an unconventional supercomputer architecture designed to simulate up to one billion biologically realistic neurons in real-time. To achieve this goal, SpiNNaker employs a novel network architecture which poses a number of practical problems in scaling up from desktop prototypes to machine room filling installations. SpiNNaker's hexagonal torus network topology has received mostly theoretical treatment in the literature. This thesis tackles some of the challenges encountered when building `real-world' systems. Firstly, a scheme is devised for physically laying out hexagonal torus topologies in machine rooms which avoids long cables; this is demonstrated on a half-million core SpiNNaker prototype. Secondly, to improve the performance of existing routing algorithms, a more efficient process is proposed for finding (logically) short paths through hexagonal torus topologies. This is complemented by a formula which provides routing algorithms with greater flexibility when finding paths, potentially resulting in a more balanced network utilisation. The scale of SpiNNaker's network and the models intended for it also present their own challenges. Placement and routing algorithms are developed which assign processes to nodes and generate paths through SpiNNaker's network. These algorithms minimise congestion and tolerate network faults. The proposed placement algorithm is inspired by techniques used in chip design and is shown to enable larger applications to run on SpiNNaker than the previous state-of-the-art. Likewise the routing algorithm developed is able to tolerate network faults, inevitably present in large-scale systems, with little performance overhead.
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Picanço, Angelo Furtado. "Uma técnica híbrida para geração de rotas em espaço geográfico com obstáculos." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=8264.
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Este trabalho está inserido no campo da Geomática e se concentra, mais especificamente, no estudo de métodos para exploração e seleção de rotas em espaços geográficos sem delimitação prévia de vias trafegáveis. As atividades que poderiam se beneficiar de estudos desse tipo estão inseridas em áreas da engenharia, logística e robótica. Buscou-se, com as pesquisas realizadas nesse trabalho, elaborar um modelo computacional capaz de consultar as informações de um terreno, explorar uma grande quantidade de rotas viáveis e selecionar aquelas rotas que oferecessem as melhores condições de trajetória entre dois pontos de um mapa. Foi construído um sistema a partir do modelo computacional proposto para validar sua eficiência e aplicabilidade em diferentes casos de estudo. Para que esse sistema fosse construído, foram combinados conceitos de sistemas baseados em agentes, lógica nebulosa e planejamento de rotas em robótica. As informações de um terreno foram organizadas, consumidas e apresentadas pelo sistema criado, utilizando mapas digitais. Todas as funcionalidades do sistema foram construídas por meio de software livre. Como resultado, esse trabalho de pesquisa disponibiliza um sistema eficiente para o estudo, o planejamento ou a simulação de rotas sobre mapas digitais, a partir de um módulo de inferência nebuloso aplicado à classificação de rotas e um módulo de exploração de rotas baseado em agentes autônomos. A perspectiva para futuras aplicações utilizando o modelo computacional apresentado nesse trabalho é bastante abrangente. Acredita-se que, a partir dos resultados alcançados, esse sistema possa ajudar a reduzir custos e automatizar equipamentos em diversas atividades humanas.This research is placed in the field of Geomatics and focuses more specifically on the study of methods for exploration and route selection in geographic areas without prior definition of trafficable roads. Activities that could benefit from such studies are embedded in areas of engineering, logistics and robotics. This study aimed to develop a computational model able to select information from a terrain, explore a lot of viable routes and select those routes that offer the best possible path between two points on a map. It was built a system from the proposed computational model to validate its effectiveness and applicability in different case studies. For this system to be built concepts of agent-based systems, fuzzy logic and route planning in robotics were combined. The information about land were organized, presented and consumed by the system created using digital maps. All features of the system were built using open source. As a result, this research provides an efficient system for the study, planning or route simulation on digital maps, using a fuzzy inference module applied to the classification of routes and a module to operate routes based on autonomous agents. The perspective for future applications using the computational model presented in this study is quite comprehensive. It is believed that from the results, this system can help reduce costs and automate equipment in various human activities.
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Hussein, Ali Abdulsattar. "Photonic Integrated Circuits Utilizing Nano-Electromechanical Systems on Silicon-on-Insulator Platform for Software Defined Networking in Elastic Optical Networks: New Insights Into Phased Array Systems, Tunable WDM, and Cascaded FIR and IIR Architectures." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39592.
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Optical communications systems operate at the limits of their margins to respond to increasing capacity demands. Some of the signal processing functions required must soon operate at speeds beyond electronic implementation. Optical signal processors are fundamentally analog which requires precise control of the operating state. Programmable optical components are consequently essential. The thesis explores and elucidates the properties of meshes of generalized Mach-Zehnder interferometers (GMZIs) amenable to silicon (Si) photonics integration that are based on multimode interference couplers with programmability achieved via voltage controlled phase-shift elements within the interferometer arms to perform a variety of finite impulse response (FIR) and infinite impulse response (IIR) signal processing functions.
The thesis presents a novel class of integrated photonic phased array systems with a single-stage, multistage, and feedback architectures. The designed photonic integrated systems utilize nano-electromechanical-system (NEMS) operated phase shifters of cascaded free suspended slot waveguides that are compact and require a small amount of power to operate. The structure of the integrated photonic phased array switch (IPPAS) elements is organized such that it brings the NEMS-operated phase shifters to the exterior sides of the construction; facilitating electrical connection. The transition slot couplers used to interconnect the phase shifters to the rest of the silicon structure are designed to enable biasing one of the silicon beams of each phase shifter from an electrode located at the side of the phase shifter. The other silicon beam of each phase shifter is biased through the rest of the silicon structure of the fabric, which is taken as a ground. Phased array processors of 2×2 and 4×4 multiple-input-multiple-output (MIMO) ports are conveniently designed within reasonable footprints native to the current fabrication technologies. The response of the single-stage 4×4 broadband IPPAS element is determined, and its phase synthesis states required for single-throw, double-throw and broadcast routing operations are predicted. The transmission responses of the single-stage wavelength division multiplexing (WDM) processors of 2×2 and 4×4 MIMO ports are simulated. The wavelength steering capability of the transmission interferograms by applying progressive phase shifts through the array of NEMS-operated phase shift elements of the single-stage 4×4 WDM (de)multiplexer is demonstrated.
The advantages of cascading broadband and WDM phased array sections are articulated through several study cases. Five different cascaded phased array architectures are trialed for the construction of non-blocking 4×4 IPPAS broadband switches that are essential elements in the construction of universal photonic processors. A cascaded 2×2 WDM (de)multiplexer that can set the bandwidth of the (de)multiplexed cyclic channels into a binary number of programmable values is demonstrated. The envelope and wavelength modulations of the transmission responses utilizing a cascaded forward structure of three 2×2 sections that can be utilized for the (de)multiplexing of different bandwidth channels are demonstrated providing individual wavelength steering capability of the narrowband and wideband channels and the individual wavelength steering capability of the slow envelope and wavelength modulating functions. Innovative universal 2×2 and 4×4 cascaded phased array processors of advanced high-order architectures that can function as both non-blocking broadband routers and tunable WDM (de)multiplexers with spectrum steering and bandwidth control of the (de)multiplexed demands are introduced.
The multimode interference (MMI) coupler is utilized for the construction of several IIR feedback photonic processors. Tunable photonic feedback processors have the advantage of using less number of MMI couplers compared to their counterparts of FIR forward-path processors saving on the footprint and loss merits. A passive feedback 2×2 (de)multiplexer made of a 4×4 MMI coupler and two loopback paths is proposed. The inclusion of an imbalance in the lengths of the loopback paths of the same symmetrical feedback (de)multiplexer is demonstrated to achieve wavelength modulation of the (de)multiplexed transmission responses that are useful for the (de)multiplexing of different bandwidth channels. Several newly introduced IIR feedback architectures are demonstrated to function similarly as their counterparts of FIR forward-path processors as binary bandwidth variable (de)multiplexers, envelope and wavelength modulation (de)multiplexers, and universal feedback processors.
The investigation provided in this thesis is also supported with dynamic zero-pole evolution analysis in the complex plane of analysis of the studied FIR and IIR photonic processors to enhance understanding the principle of operation. This research expands the prospective for constructing innovative silicon-on-insulator (SOI) based optical processors for applications in modern optical communication systems and programmable elastic optical networks (EONs).
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Chiang, Hung-Yi, and 江鴻毅. "Comparing IPv6 and NAT on Software-based Router Performance." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/94491772571592939939.
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碩士國立宜蘭大學
資訊工程學系碩士班
103
Current IPv4 (Internet Protocol version 4) address space does not fulfill the Internet requirement. There are two major solutions which are IPv6 (Internet Protocol version 6) and NAT (Network Address Translation). IPv6 not only solves the IP address shortage problem but also provides new functions such as address auto-configuration and mobility. Therefore, IPv6 is more and more important in the next generation Internet. In the existing articles, most researchers investigate the performance of the IPv4 and IPv6. However, the performance of NAT and IPv6 should be measured and compared for selecting the suitable solution for the next generation Internet. This thesis adopts Linux to build a software router for NAT or IPv6. Then we utilize SmartBits 600B to test the throughput, the Maximum throughput, the latency and the packet loss rate for the NAT and IPv6 software router. Finally, we use IPv4 as the base line to discuss the performance.
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Hsu, Chin-Ying, and 許晉熒. "An Implementation of a Diff-Serv-aware Software Router on Linux." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/17806500935365915673.
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碩士國立雲林科技大學
電機工程系碩士班
89
A Quality of Service (QoS) guarantee has become a must and a challenge for the ever-blocking Internet. A variety of strategies have been proposed ever since. Intergrated Service formulated by Internet Engineering Task Force (IETF) facilitates a better QoS, but its Resource reSerVation Protocol (RSVP) suffers a drawback of poor scalability. Therefore, a new strategy called Differentiated Server has been formulated by IETF to improve Integrated Service and reduce the complexity in implementations. Thanks to its openness, Linux operating system has been adopted by many researchers as their operating platform. The ever-updating Linux has developed many traffic control functions, which are indispensable elements in implementing Diff-Serv on Linux. In this paper we design a program on the user-space of Linux to exploit traffic control functions to implement Diff-Serv-aware software core routers and edge routers. Furthermore, we examine the functions of the software routers through ten experiments. Experimental results show that both our core router and edge router can correctly deal with the differentiated services codepoint (DSCP) within packets and offer Diff-Serv-aware service.
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CIANFRANI, ANTONIO. "Software router: OSPF performance evaluation and enhancement through a new multi-path incremental algorithm." Doctoral thesis, 2008. http://hdl.handle.net/11573/916977.
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Ghonaim, Fahad A. "Adaptive router bypass techniques to enhance core network efficiency." Thesis, 2018. https://dspace.library.uvic.ca//handle/1828/9283.
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Internet traffic is increasing exponentially, driven by new technologies such as Internet of Things (IoT) and rich streaming media. The traditional IP router becomes a bottleneck for further Internet expansion due to its high power consumption and inefficiency in processing the growing traffic. Router bypass has been introduced to overcome capacity limitations and the processing costs of IP routers. With router bypass, a portion of traffic is provisioned to bypass the router and is switched by the transport layer. Router bypass has shown to provide significant savings in network costs. These advantages are limited by a reduction in the statistical multiplexing associated with the subdivision of the available bandwidth typically into bypass and traditional portions thus limiting the interest in bypass techniques.
This thesis will explore multiple techniques to enhance the efficiency of router bypass. The main goals are to address the issue of the reduction in statistical multiplexing and to add a dynamic approach to the router bypass mechanism. The recent advancements in the Optical Transport Network (OTN) play a major role in the transport network. This proposal takes full advantage of OTN in the router-bypassing context by applying recent developments such as Hitless Adjustments ODUflex (HAO), which
allow the provisioned channels to be adjusted without re-establishing the connections.
In addition, it will allow the bypassing mechanism to be flexible enough to meet the traffic behaviour needs of the future. This thesis will study multiple approaches to enhance the router bypass mechanism including: an adaptive provisioning style using various degrees of provisioning granularities and controlling the provisioning based on traffic behaviour. In addition, this thesis will explore the impact of automation in Software-Defined Networking (SDN) on router bypass. The application-driven infrastructure in SDN is moving the network to be more adaptive, which paves the way for an enhanced implementation of router bypass. Many challenges still face the industry to fully integrate the three layers (3, 2, and 1) to transform the current infrastructure into an adaptive application driven network. The IP router (layer 3) provisions and restores the connection regardless of the underlying layers (layer 2 and 1) and the transport layer does the same regardless of the IP layer. Although allowing every layer to develop without being constrained by other layers offers a huge advantage, it renders the transport layer static and not fully aware of the traffic behaviour. It is my hope that this thesis is a step forward in transforming the current network into a dynamic, efficient and responsive network. A simulation has been built to imitate the router bypassing concept and then many measurements have been recorded.Graduate
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"Modeling TCP/IP software implementation performance and its application for software routers." Universitat Politècnica de Catalunya, 2002. http://www.tesisenxarxa.net/TDX-0216104-094559/.
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Wu, Chien-chan, and 吳建璋. "Software Implementation of a Configurable Design of Interconnection Routers." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/16683721511454782922.
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碩士國立中山大學
電機工程學系研究所
101
In the development process of hardware system designs, effective design integration and design reuse can reduce system development time. Our previous research on configurable design method plays one way to support such design capability. In this research, we apply our configurable design method in designing and implementing configurable design of hardware router designs. We systematically decomposed a router design into a number of hierarchical functional module units. We also designed various parameterized functional designs of different functional characteristics for each kind of configurable module unit. They form basic units and organization of the configurable router design. Design engineers can plan detailed router functional composition according to specific system requirements of router designs. Then, they can map planned design composition onto design parameters of various composed module units and perform the configuration task to generate the required router design. In this research, we implemented configurable designs and organization of configurable module units of router designs. We also performed configuration experiments of module units and integrated routers to validate that the implementation effectively achieves the goal of this research.
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Hwang, Po-Chun, and 黃柏鈞. "Intelligent Route Selection with Congestion Avoidance in Software Defined Networks." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/8vr8bn.
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碩士國立高雄科技大學
電機工程系
107
Nowadays, network is getting more popular, how to improve the efficiency of data transmission is an important issue. In Software Defined Network(SDN), the research of routing is divided into static path routing and dynamic path routing. Static path routing does not change path during data transmit, causing single link burden is too large and packet loss. Dynamic path routing get data plane information through control plane period monitor data plane and change path according different situation, it solve the problem of static path routing, but there is not a better monitor period setting rule in related research. Otherwise, new path configuration needs reaction time, before new path is configured, packet loss is still happened. In addition, dynamic path routing can not modify the routing decision based on the past experience. Artificial neural network use training data to train the neural network model iteratively, help the neural network model have the ability to predict result based on new data. In the paper, we proposed an Intelligent Route based on Network Traffic(IRNT), adding neural network into SDN control plane, and select more suitable path selected according different load, decreasing the impact of monitor period and path configure time to improve network performance.
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Brata, Adam Hendra, and 韓亞當. "Software Development of Automatic Data Collector for Bus Route Planning System." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/25571508336093832941.
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碩士國立中央大學
資訊工程學系
102
Public transportation is important issue in Taiwan. Recently, mobile application named Bus Route Planning was developed to help the user to get information about public transportation using bus. But, this application often gave the user inaccurate bus information and this application has less attractive GUI. To overcome those two problems, we need two kinds of solutions. First, we need a more accurate time prediction algorithm to predict the arrival time of bus. Second, we can use augmented reality technology to make an GUI improvement. In this thesis, we proposed a Automatic Data Collector system that have ability to gave a support for those two solutions at once. This proposed system has two main functionalities. First, data collector function to provide us data set that can be further analyzed as an base of time prediction algorithm. Second, data updater function to provide us the most updated bus information to used in augmented reality system. Additionally, beside those two mentioned functions, we add one additional data management function to give our system better functionality to support those two related systems. We developed this proposed system using batch data processing scenario and SQL native query in Java programming language. Finally, after we done some testing, we conclude that our proposed system is better than the current server system and the data processing scenario that used in our proposed system was very effective to made database manipulation especially for large-sized data. Keywords : Automated System, Bus Route Planning, Java Server Application, Data Collector
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Pan, Dung-Yuan, and 潘東元. "Implementation of Software Routers on Obsolete Light Computers in Campuses Based on BrazilFW Linux-based Embedded Systems." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/98941309712133922362.
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碩士淡江大學
資訊工程學系碩士在職專班
98
Embedded systems stress maximum utilization of limited hardware for specific purposes. BrazilFW is a free and powerful Linux-based software router. It supports L7 firewall and offers QoS management without using a large amount of hardware resources. This study attempted to make use of old and obsolete computers by implementing BrazilFW on them to provide routing and firewall services in elementary school campuses. The purpose of this study was to make use of old computers in elementary schools, especially those located in remote areas and having limited funds and resources. BrazilFW is free software, so it can be downloaded for free and modified without restrictions. Moreover, it is also easy to use. Therefore, BrazilFW can help schools save a huge amount of costs of procuring and maintaining routers and firewall systems and also be modified according to the environmental needs of each school. Customization of this software can be realized through installation and application of optional applications needed by campuses in different scales.
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Boughzala, Bochra. "Netlang : un langage de haut niveau pour les routeurs programmables dans le contexte des réseaux SDN." Mémoire, 2013. http://www.archipel.uqam.ca/5800/1/M12992.pdf.
Full textAbstract:
Développer des applications réseaux pour des routeurs programmables basés sur les Network Processors (NPs) implique l'utilisation de langages de bas-niveau et d'outils propriétaires fortement dépendants des architectures matérielles sous-jacentes. Le code source, généralement écrit en langage assembleur, n'est pas facile à écrire et cause des problèmes de maintenance. Les applications résultantes sont également difficiles à déboguer. Dans ce mémoire nous proposons NETLANG, un nouveau langage de programmation de haut-niveau dédié aux NPs. De plus d'être un langage simple et élégant, de réduire les coûts de développement et de la maintenance, et d'améliorer la réutilisation du code, NETLANG a pour objectif essentiel de décrire le comportement des paquets dans un NP. NETLANG est un langage qui permet de développer des applications de traitement de paquets. Il établit deux niveaux. Le premier niveau du langage offre une abstraction et une description du routeur à travers un pipeline de tables OpenFlow et des règles de forwarding ayant l'aptitude d'être modifiées dynamiquement et donc de permettre de changer le comportement du routeur à la volée. La sémantique du langage est inspirée du protocole OpenFlow qui a permis d'exprimer les principales tâches de traitement de paquets telles que le parsing, le lookup et la modification. Le langage est bâti en respectant le modèle des Software Defined Networks (SDNs) qui définit un nouveau plan de séparation entre le control plane et le data plane. Le deuxième niveau de NETLANG est traduit en matériel et permet l'adaptabilité du langage à plusieurs plateformes. Des adaptateurs spécifiques à des plateformes différentes sont intégrés au compilateur de NETLANG et permettent de rendre le langage portable. En effet, nous avons utilisé deux environnements pour l'implémentation de NETLANG ; le NP4 d'EZchip caractérisé par sa structure de TOPs (Task Optimized Processors) en pipeline et le NFP-3240 de Netronome connu pour son parallélisme et l'exploitation du multithreading. La validation de NETLANG s'est basée sur un ensemble d'applications réseau ayant des complexités et des domaines différents. A travers ce mémoire nous avons démontré qu'on est capable d'avoir aujourd'hui un langage pour les routeurs programmables. La sémantique d'OpenFlow, sur laquelle nous avons basé notre langage NETLANG, est suffisante et même pertinente en termes de description de comportement des paquets dans un NP.
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MOTS-CLÉS DE L’AUTEUR : langages à domaine spécifique, réseaux programmables, processeurs de réseau.
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Криськова, Світлана Андріївна, and Svitlana Kryskova. "Дослідження та побудова геоінформаційної карти «Видатні українські вчені»." Bachelor's thesis, 2021. http://elartu.tntu.edu.ua/handle/lib/35761.
Full textAbstract:
Кваліфікаційна робота присвячена побудові та дослідженню геоінформаційної карти «Видатні українські вчені».
Мета роботи: побудова та дослідження геоінформаційної карти «Видатні українські вчені».
В першому розділі кваліфікаційної роботи розглянуто основні характеристики геоінформаційних систем. Також описано історію виникнення та розвитку геоінформаційних систем у світі. Для якісного використання та розуміння принципів роботи даних систем досліджено їхнє застосування та функції. Представлено основну та додаткову класифікацію геоінформаційних систем.
В другому розділі кваліфікаційної роботи розглянуто програмне забезпечення для роботи з геоінформаційними системами та проведено їх аналіз. Складено основні вимоги до програмного забезпечення та на їхній основі обрано найкраще, а саме Google Maps. Далі відбулась робота з електронними таблицями, а саме створення бази даних із відомостями про вчених. На основі бази даних створено геоінформаційну карту «Видатні українські вчені» з використанням програмного забезпечення.Qualification work is devoted to the construction and research of geographic information map "Outstanding Ukrainian scientists". Purpose: construction and research of geographic information map "Outstanding Ukrainian scientists". The first section of the qualification work considers the main characteristics of geographic information systems. The history of the origin and development of geographic information systems in the world is also described. For high-quality use and understanding of the principles of operation of these systems, their application and functions have been studied. The basic and additional classification of geographic information systems is presented. In the second section of the qualification work the software for work with geographic information systems is considered and their analysis is carried out. The basic requirements for the software are made and based on them the best one is chosen, namely Google Maps. Then there was work with spreadsheets, namely the creation of a database with information about scientists. Based on the database, a geoinformation map "Outstanding Ukrainian scientists" was created using software.
ВСТУП 7 Розділ 1 Загальні теоретичні відомості про геоінформаційні системи 9 1.1 Характеристика геоінформаційних систем 9 1.1.1 Історія виникнення та розвитку геоінформаційних систем 10 1.1.2 Класифікація геоінформаційних систем 13 1.1.3 Різновиди карт 16 1.2 Застосування геоінформаційних систем 20 1.3 Функції роботи геоінформаційних систем 22 1.4 Висновок до першого розділу 24 Розділ 2 Створення геоінформаційної карти «видатні українські вчені» 26 2.1 Аналіз існуючого та вибір оптимального програмного забезпечення для ГІС 26 2.2 Створення бази даних «Видатні українські вчені» 28 2.3 Побудова геоінформаційної карти «Видатні українські вчені» 32 2.4 Висновок до другого розділу 39 Розділ 3 Безпека життєдіяльності, основи охорони праці 40 3.1 Долікарська допомога при переломах 40 3.2 Оцінка стану охорони праці на підприємстві 43 3.3 Висновок до третього розділу 45 ВИСНОВКИ 46 СПИСОК ВИКОРИСТАНИХ ДЖЕРЕЛ 48
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Santos, Ângelo Filipe da Silva dos. "Sumarização automática de texto." Master's thesis, 2012. http://hdl.handle.net/10400.6/3738.
Full textAbstract:
O acto de sumarizar ou resumir, isto é, tornar mais sucinta a descrição de uma ideia ou conceito, é uma actividade bastante trivial. As pessoas produzem constantemente, este tipo de representações sucintas para algo que pretendam descrever ou comunicar, sendo que, uma forma muito comum de síntese são os sumários escritos. Tradicionalmente este tipo de sumários são manualmente produzidos por pessoas que analisam textos e tentam identi car os principais conceitos
presentes nos mesmos. A chamada sobrecarga de informação , em muito potenciada pela explosão da Internet, tem instigado a disponibilidade de um cada vez maior volume de informação, que torna esse trabalho manual bastante difícil, senão mesmo impossível. Vários
têm sido os esforços realizados na tentativa de resolução deste problema, procurando desenvolver técnicas que possibilitem obter o conteúdo mais relevante de documentos, de maneira condensada, sem alterar o seu signi cado original, e com a mínima intervenção humana.
O trabalho desenvolvido no âmbito desta dissertação visou explorar diversas abordagens de sumarização extractiva de texto através da implementação de métodos computacionais baseados em estatísticas textuais e teoria de grafos. Foi ainda implementado um método baseado na fusão das abordagens anteriores com outras características como a procura de palavras- -chave e a posição das frases no texto, o que resultou na denominação de método híbrido. A sumarização realizada é puramente extractiva, ou seja, a composição do sumário gerado é baseada na classi cação das frases do texto original e posterior selecção do subconjunto das frases mais informativas, por forma a satisfazer determinada taxa de compressão.
Numa abordagem puramente estatística, foi desenvolvido um método que pretende avaliar a
relevância de termos do texto com base nos valores das suas frequências, no texto fonte e num corpus. A abordagem baseada em teoria de grafos foi utilizada para levar a cabo duas tarefas distintas, a classi cação de frases através da avaliação da sua centralidade, e a extracção de palavras-
chave. A abordagem híbrida utiliza as várias características descritas numa combinação
linear, mediada por um conjunto de pesos associados às diversas componentes.
O desempenho das diferentes abordagens exploradas é avaliado utilizando colecções de textos noticiosos. Estes dados são provenientes das Document Understanding Conferences (DUC). Para avaliar a qualidade dos sumários produzidos, foi utilizada a ferramenta ROUGE. Os diversos métodos propostos foram, então, comparados entre si avaliando-se intrínseca e automaticamente
o nível de informação dos extractos produzidos. Os resultados obtidos evidenciam que o método híbrido é o que apresenta melhor desempenho aquando da comparação da sua pontuação ROUGE com os demais, cando esta tendência a dever-se essencialmente à utilização de uma heurística posicional que atribui maior importância a frases que ocupem uma posição cimeira no texto, sendo que este modelo se adequa especialmente bem à estrutura textual de artigos noticiosos.
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Pamulapati, Santhan. "Link failure detection in OSPF network using OpenFlow protocol." Thesis, 2014. http://hdl.handle.net/1805/4443.
Full textAbstract:
Indiana University-Purdue University Indianapolis (IUPUI)The study of this thesis is focused on reducing the link failure detection time in OSPF network. When a link failure occurs, OSPF protocol detects it using RouterDeadInterval time. This timer is fired only after a predefined time interval, thus increasing the time of convergence after the link failure. There are previous studies to reduce the RouterDeadInterval time, but they introduce other effects which are discussed later in the thesis. So, a novel approach is proposed in this thesis to reduce the link failure detection time with the help of emerging network architecture Software Defined Networking (SDN) and OpenFlow Protocol.