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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.
191

Aplicación de cadenas de Markov en protocolos de comunicación

Villanueva Morán, Claudia Isabel 09 May 2011 (has links)
En este trabajo se explica cómo funciona la transferencia de datos y qué políticas de control siguen los protocolos Aloha Puro y el Aloha Ranurado para evitar y gestionar las colisiones. Se realiza la programación de un modelo de cadenas de Markov para cada uno de los protocolos y con ayuda del programa SCILAB se simulan los rendimientos que éstos en diferentes escenarios. / Tesis
192

Medición y análisis de tráfico en redes MPLS / Javier Igor Doménico Luna Victoria García

Luna Victoria García, Javier Igor Doménico 09 May 2011 (has links)
La presente tesis se inicia con el estudio de los parámetros más resaltantes de MPLS (Multi Protocol Label Switching) tecnología que nos permite afrontar los múltiples requerimientos que las nuevas aplicaciones necesitan, en especial, las aplicaciones en línea denominadas en tiempo real bajo los esquemas que la ITUT recomienda. Durante el desarrollo de esta tesis se definen escenarios de redes IP; a los cuales serán sometidos a diversos tráficos; se evaluaran los comportamientos resultantes de la interacción con estos tráficos y se comprobará la mejor alternativa tecnológica para proporcionar QoS, Ingeniería de Tráfico, transmisión óptima de información, uso de recursos de red, entre otras características que son de interés. / Tesis
193

Reliable video transmission over internet.

January 2000 (has links)
by Sze Ho Pong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 50-[53]). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Related Work --- p.3 / Chapter 1.2 --- Contributions of the Thesis --- p.3 / Chapter 1.3 --- Organization of the Thesis --- p.4 / Chapter 2 --- Background --- p.5 / Chapter 2.1 --- Best-effort Internet - The Lossy Network --- p.5 / Chapter 2.2 --- Effects of Packet Loss on Streamed Video --- p.7 / Chapter 2.3 --- Loss Recovery Schemes in Video Streaming --- p.8 / Chapter 3 --- Comparison of Two Packet-Loss Detection Schemes --- p.10 / Chapter 3.1 --- Gap Detection (GD) --- p.12 / Chapter 3.2 --- Time-Out (TO) Detection --- p.14 / Chapter 3.3 --- Mathematical Comparison --- p.17 / Chapter 4 --- The Combined Loss-Detection Algorithm --- p.21 / Chapter 4.1 --- System Architecture --- p.22 / Chapter 4.2 --- Loss Detection and Recovery --- p.23 / Chapter 4.2.1 --- Detecting Data Packet Losses Transmitted for First Time --- p.24 / Chapter 4.2.2 --- Detecting Losses of Retransmitted Packet --- p.28 / Chapter 4.3 --- Buffering Techniques --- p.32 / Chapter 4.3.1 --- Determining Packet-Loss Rate in Presentation --- p.33 / Chapter 4.4 --- Mapping Packet-Loss Rate to Degradation of Video Quality --- p.38 / Chapter 5 --- Experimental Results and Analysis --- p.40 / Chapter 5.1 --- Experimental Setup --- p.40 / Chapter 5.2 --- Small Delay Jitter Environment --- p.42 / Chapter 5.3 --- Large Delay Jitter Environment --- p.44 / Chapter 5.3.1 --- Using Low Bit-Rate Stream --- p.44 / Chapter 5.3.2 --- Using High Bit-Rate Stream --- p.44 / Chapter 6 --- Conclusions and Future Work --- p.47 / Chapter 6.1 --- Conclusions --- p.47 / Chapter 6.2 --- Future Work --- p.49 / Bibliography --- p.50
194

An asynchronous time division multiplexing scheme for voice over IP.

January 2000 (has links)
by Yip Chung Sun Danny. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 52-54). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.2 --- Organization of Thesis --- p.5 / Chapter Chapter 2 --- Background --- p.6 / Chapter 2.1 --- Speech Codec --- p.6 / Chapter 2.2 --- RTP/UDP/IP Header Compression --- p.7 / Chapter 2.2.1 --- Real-Time Transport Protocol --- p.7 / Chapter 2.2.2 --- RTP/UDP/IP Header Compression --- p.8 / Chapter Chapter 3 --- Scenario and Assumptions --- p.10 / Chapter Chapter 4 --- Asynchronous Time Division Multiplexing Scheme --- p.14 / Chapter 4.1 --- Basic Idea --- p.14 / Chapter 4.1.1 --- Bandwidth Efficiency Improvement --- p.16 / Chapter 4.1.2 --- Delay Reduction --- p.18 / Chapter 4.2 --- Header Compression --- p.19 / Chapter 4.2.1 --- Header Compression Process --- p.21 / Chapter 4.2.2 --- Context Mapping Table --- p.23 / Chapter 4.3 --- Protocol --- p.28 / Chapter 4.3.1 --- UNCOMPRESSED_RTP Mini-Header --- p.30 / Chapter 4.3.2 --- SYNCHRONIZATION Mini-header --- p.31 / Chapter 4.3.3 --- COMPRESSED´ؤRTP Mini-header --- p.32 / Chapter 4.4 --- Connection Establishment --- p.33 / Chapter 4.4.1 --- Addressing Phase --- p.34 / Chapter 4.4.2 --- Connection Phase --- p.36 / Chapter 4.5 --- Software Implementation --- p.38 / Chapter Chapter 5 --- Simulation Results --- p.39 / Chapter 5.1 --- Simulation Model --- p.39 / Chapter 5.2 --- Voice Source Model --- p.41 / Chapter 5.3 --- Simulation Results --- p.43 / Chapter 5.3.1 --- Network Utilization and Delay Performance --- p.43 / Chapter 5.3.2 --- Number of Supported Connections --- p.45 / Chapter Chapter 6 --- Conclusion and Future Work --- p.49 / Bibliography --- p.52
195

TCP-friendly video transmission over the internet.

January 2001 (has links)
by Chan Ho Chow. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 65-67). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Background --- p.5 / Chapter 2.1. --- Packet Loss in the Internet --- p.5 / Chapter 2.2. --- Shared Internet --- p.7 / Chapter 2.3. --- Video Streaming --- p.10 / Chapter 2.4. --- Real-time video transmission criteria --- p.11 / Chapter 2.5. --- Existing Video Streaming Protocol --- p.13 / Chapter Chapter 3 --- Transmission Control Protocol (TCP) --- p.16 / Chapter Chapter 4 --- Variable-rate Streaming TCP (VarS-TCP) --- p.22 / Chapter 4.1. --- General Idea --- p.22 / Chapter 4.2. --- Assumptions --- p.25 / Chapter 4.3. --- VarS-TCP Algorithm --- p.26 / Chapter 4.3.1. --- Connection Initialization --- p.26 / Chapter 4.3.2. --- Normal Data Transfer --- p.27 / Chapter 4.4. --- Skipping packets in TCP --- p.32 / Chapter 4.4.1. --- Types of skipped packet --- p.32 / Chapter 4.4.2. --- Acknowledging skipped packets --- p.34 / Chapter 4.4.3. --- Maintaining Normal Data Flow --- p.35 / Chapter 4.4.4. --- Congestion Control --- p.37 / Chapter 4.4.5. --- Packets skipped by receiver --- p.41 / Chapter 4.5. --- Rebuffering --- p.44 / Chapter Chapter 5 --- Simulation Result --- p.45 / Chapter 5.1. --- Accumulating Data --- p.46 / Chapter 5.2. --- Delay Constraints --- p.48 / Chapter 5.3. --- Adapting network situation --- p.50 / Chapter 5.4. --- Sharing bandwidth with TCP --- p.52 / Chapter 5.5. --- Random Traffic --- p.58 / Chapter 5.6. --- Effect of packet skip threshold --- p.59 / Chapter 5.7. --- Effect of round-trip-time --- p.61 / Chapter Chapter 6 --- Conclusion and Future Works --- p.63 / Bibliography --- p.65
196

Congestion control and QoS provisioning in IP networks.

January 2002 (has links)
Hua Cunqing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 53-56). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Congestion Control in the IP Network --- p.1 / Chapter 1.2 --- Quality of Service in the IP network --- p.2 / Chapter 1.3 --- Structure of Thesis --- p.3 / Chapter 2 --- Background --- p.4 / Chapter 2.1 --- TCP and Congestion Control --- p.4 / Chapter 2.1.1 --- Slow Start --- p.4 / Chapter 2.1.2 --- Congestion Avoidance --- p.5 / Chapter 2.1.3 --- "Fast Retransmit, Fast Recovery and Timeout" --- p.5 / Chapter 2.2 --- Active Queue Management --- p.7 / Chapter 2.3 --- Integrated Services and Differentiated Services --- p.8 / Chapter 3 --- The Fairness of TCP Vegas in Networks with Multiple Congested Gate- ways --- p.10 / Chapter 3.1 --- Introduction --- p.10 / Chapter 3.2 --- TCP Vegas and related works --- p.11 / Chapter 3.3 --- Analysis --- p.13 / Chapter 3.4 --- Simulation Results --- p.15 / Chapter 3.4.1 --- Throughput for different number of active cross connections --- p.16 / Chapter 3.4.2 --- Throughput for different number of flows in each connection --- p.17 / Chapter 3.4.3 --- Multiple congestion vs Single congestion --- p.17 / Chapter 3.5 --- Summary --- p.19 / Chapter 4 --- The Joint Congestion Control for TCP/IP Networks --- p.21 / Chapter 4.1 --- Background --- p.21 / Chapter 4.2 --- The Joint Congestion Control --- p.23 / Chapter 4.2.1 --- Path Load Reduction Factor --- p.23 / Chapter 4.2.2 --- The Congestion Control Algorithm --- p.24 / Chapter 4.2.3 --- Probing Interval --- p.26 / Chapter 4.2.4 --- Parameter Setting --- p.26 / Chapter 4.2.5 --- Encoding of R --- p.27 / Chapter 4.3 --- Simulation Results --- p.28 / Chapter 4.3.1 --- Congestion Window Behavior --- p.28 / Chapter 4.3.2 --- Throughput Stability --- p.31 / Chapter 4.3.3 --- Packet Loss Ratio --- p.31 / Chapter 4.3.4 --- Fairness Index --- p.32 / Chapter 4.3.5 --- Fairness in Multiple-hop Network --- p.32 / Chapter 4.3.6 --- Parameter Sensitivity --- p.33 / Chapter 4.3.7 --- Interaction between JCC and Reno flows --- p.35 / Chapter 4.4 --- Summary --- p.35 / Chapter 5 --- S-WTP : Shifted Waiting Time Priority Scheduling for Delay Differ- entiated Services --- p.37 / Chapter 5.1 --- Introduction --- p.37 / Chapter 5.2 --- Scheduling Algorithms for Delay Differentiated Services --- p.38 / Chapter 5.3 --- Shifted Waiting Time Priority Scheduling --- p.41 / Chapter 5.3.1 --- Local Update --- p.42 / Chapter 5.3.2 --- Global Update --- p.42 / Chapter 5.3.3 --- Computational overhead --- p.42 / Chapter 5.4 --- Simulation Results --- p.43 / Chapter 5.4.1 --- Microscopic View of Individual Packet Delay of S-WTP and WTP --- p.43 / Chapter 5.4.2 --- Delay Ratios in Different Timescales --- p.44 / Chapter 5.4.3 --- Effects of aggregate traffic and class load distribution on delay ratio --- p.44 / Chapter 5.4.4 --- Delay Ratios with More Classes --- p.48 / Chapter 5.5 --- Summary --- p.48 / Chapter 6 --- Conclusions --- p.50 / Chapter 6.1 --- Congestion Control --- p.50 / Chapter 6.2 --- Quality of Service Provision --- p.51 / Chapter 6.3 --- Final Remarks --- p.51
197

Modelo de referencia de transición de IPv4 a IPv6 para el sector gobierno de Perú

Tomy Baltazar, Marco Antonio 10 February 2017 (has links)
Ante el inminente agotamiento de las direcciones IPv4, se requiere que las organizaciones inicien la transición de sus redes y contenidos hacia el protocolo IPv6, por lo que la presente tesis tiene como finalidad proponer un modelo de referencia para iniciar el proceso de transición hacia el protocolo IPv6 en las Instituciones Públicas del Gobierno de Perú, debido a que a la fecha de publicado el presente trabajo, a nivel de gobierno, las instituciones públicas que están relacionadas directamente con el desarrollo de las telecomunicaciones y de las tecnologías de información en el Perú, no han considerado la elaboración de una metodología y/o documentos técnicos que permita a las instituciones públicas prepararse para iniciar el despliegue del protocolo IPv6 en sus redes y contenidos. El contar con un modelo de referencia y los documentos técnicos necesarios permite dinamizar la adopción del nuevo protocolo, esto se evidencia en la revisión de las acciones que vienen realizando diversos países como: Argentina, Brasil, Colombia, Chile, Estados Unidos y España, quienes a parte de definir una estrategia nacional de transición hacia IPv6, han elaborado modelos de referencia y documentos técnicos de apoyo específicos para que sus instituciones públicas puedan iniciar la transición hacia el nuevo protocolo IPv6. En ese sentido, el aporte principal del presente trabajo es presentar un modelo de referencia y documentos técnicos que sirvan de apoyo para iniciar la transición hacia el protocolo IPv6 en las instituciones públicas a nivel del Gobierno Peruano. / Tesis
198

Estudio para la implementación de redes de nueva generación (NGN) en Lima-Metropolitana

Manco Araujo, Patricia Norma 04 December 2012 (has links)
El objetivo de la presente tesis es demostrar las ventajas y beneficios de la implementación de la Red Next Generation Network (NGN) en Lima-Metropolitana. La Red NGN está basada en una serie de plataformas y protocolos, los cuales deben trabajar de una manera ordenada y jerárquica para el buen funcionamiento de la red y seguir ofreciendo los servicios actuales así como nuevos servicios de redes avanzadas, todas ellas basadas en plataformas de red IP. Se realizó un estudio mercado de los servicios ofrecidos actualmente por los operadores, en donde se puede apreciar la cantidad de clientes por servicio y la penetración de estos servicios a lo largo de los años 2007-2011. Seguidamente se presentan además los servicios que se podrían ofrecer con el desarrollo de esta tecnología, estos servicios tales como IPTV y teleconferencias, que son ofrecidos en otros países, como México y España, por ejemplo. La Ingeniería del proyecto propone la ubicación de puntos de presencia (PoP) en áreas estratégicas, de tal manera que se atienda las necesidades de los usuarios. Se propone además el tipo de topología a usar así como los elementos de red necesarios para su puesta en servicio. Finalmente se realiza el análisis financiero de los servicios ofrecidos en el sector de telecomunicaciones del mercado de Lima – Metropolitana, basando el estudio en valores obtenidos de los indicadores estadísticos del Regulador Osiptel, permitiendo demostrar la rentabilidad de la implementación de la red propuesta en la presente tesis. / Tesis
199

Diseño e implementación de un equipo electrónico para la tarifación de llamadas telefónicas en locutorios de voz IP / Christian Ricardo Palma Palacios

Palma Palacios, Christian Ricardo 09 May 2011 (has links)
El presente proyecto tiene por título: Diseño e Implementación de un Equipo Electrónico para la Tarifación de Llamadas Telefónicas en Locutorios de Voz IP, donde un locutorio se entiende como un conjunto de líneas telefónicas, Voz IP hace referencia a la tecnología que transmite la voz sobre una red IP y la tarifación es el proceso por el cual asignamos un valor monetario (costo) a una llamada telefónica. / Tesis
200

Defending against low-rate TCP attack: dynamic detection and protection.

January 2005 (has links)
Sun Haibin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 89-96). / Abstracts in English and Chinese. / Abstract --- p.i / Chinese Abstract --- p.iii / Acknowledgement --- p.iv / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Background Study and Related Work --- p.5 / Chapter 2.1 --- Victim Exhaustion DoS/DDoS Attacks --- p.6 / Chapter 2.1.1 --- Direct DoS/DDoS Attacks --- p.7 / Chapter 2.1.2 --- Reflector DoS/DDoS Attacks --- p.8 / Chapter 2.1.3 --- Spoofed Packet Filtering --- p.9 / Chapter 2.1.4 --- IP Traceback --- p.13 / Chapter 2.1.5 --- Location Hiding --- p.20 / Chapter 2.2 --- QoS Based DoS Attacks --- p.22 / Chapter 2.2.1 --- Introduction to the QoS Based DoS Attacks --- p.22 / Chapter 2.2.2 --- Countermeasures to the QoS Based DoS Attacks --- p.22 / Chapter 2.3 --- Worm based DoS Attacks --- p.24 / Chapter 2.3.1 --- Introduction to the Worm based DoS Attacks --- p.24 / Chapter 2.3.2 --- Countermeasures to the Worm Based DoS Attacks --- p.24 / Chapter 2.4 --- Low-rate TCP Attack and RoQ Attacks --- p.26 / Chapter 2.4.1 --- General Introduction of Low-rate Attack --- p.26 / Chapter 2.4.2 --- Introduction of RoQ Attack --- p.27 / Chapter 3 --- Formal Description of Low-rate TCP Attacks --- p.28 / Chapter 3.1 --- Mathematical Model of Low-rate TCP Attacks --- p.28 / Chapter 3 2 --- Other forms of Low-rate TCP Attacks --- p.31 / Chapter 4 --- Distributed Detection Mechanism --- p.34 / Chapter 4.1 --- General Consideration of Distributed Detection . --- p.34 / Chapter 4.2 --- Design of Low-rate Attack Detection Algorithm . --- p.36 / Chapter 4.3 --- Statistical Sampling of Incoming Traffic --- p.37 / Chapter 4.4 --- Noise Filtering --- p.38 / Chapter 4.5 --- Feature Extraction --- p.39 / Chapter 4.6 --- Pattern Matching via the Dynamic Time Warping (DTW) Method --- p.41 / Chapter 4.7 --- Robustness and Accuracy of DTW --- p.45 / Chapter 4.7.1 --- DTW values for low-rate attack: --- p.46 / Chapter 4.7.2 --- DTW values for legitimate traffic (Gaussian): --- p.47 / Chapter 4.7.3 --- DTW values for legitimate traffic (Self-similar): --- p.48 / Chapter 5 --- Low-Rate Attack Defense Mechanism --- p.52 / Chapter 5.1 --- Design of Defense Mechanism --- p.52 / Chapter 5.2 --- Analysis of Deficit Round Robin Algorithm --- p.54 / Chapter 6 --- Fluid Model of TCP Flows --- p.56 / Chapter 6.1 --- Fluid Math. Model of TCP under DRR --- p.56 / Chapter 6.1.1 --- Model of TCP on a Droptail Router --- p.56 / Chapter 6.1.2 --- Model of TCP on a DRR Router --- p.60 / Chapter 6.2 --- Simulation of TCP Fluid Model --- p.62 / Chapter 6.2.1 --- Simulation of Attack with Single TCP Flow --- p.62 / Chapter 6.2.2 --- Simulation of Attack with Multiple TCP flows --- p.64 / Chapter 7 --- Experiments --- p.69 / Chapter 7.1 --- Experiment 1 (Single TCP flow vs. single source attack) --- p.69 / Chapter 7.2 --- Experiment 2 (Multiple TCP flows vs. single source attack) --- p.72 / Chapter 7.3 --- Experiment 3 (Multiple TCP flows vs. synchro- nized distributed low-rate attack) --- p.74 / Chapter 7.4 --- Experiment 4 (Network model of low-rate attack vs. Multiple TCP flows) --- p.77 / Chapter 8 --- Conclusion --- p.83 / Chapter A --- Lemmas and Theorem Derivation --- p.85 / Bibliography --- p.89

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