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

Internet Protocol based Mobile Radio Access Network Architecture for Remote Service Areas

Shahzad, Hamid, Jain, Nishant January 2007 (has links)
When it comes to their Radio Access Network (RAN) infrastructure, no two Mobile Operators, serving remote service areas, are alike. Despite situations and technologies being diverse, a well designed optimized RAN solution must adapt itself to the existing networking technologies, both with regard to legacy core networks and modern telecommunication networks in order to produce the best network which is possible subject to many constraints. There is a misconception in technical circles that an optimized internet protocol (IP) enabled RAN architecture is more theoretical than practical. On the contrary, the aforesaid is highly dependent on the technology used. Packet optimized IP- GSM Radio Access Network (GRAN) architecture is proposed in this thesis, it uses Internet Protocol (IP) rather than proprietary protocols for communication between Base Transceiver Stations (BTS), Base Station Controllers (BSC), and the Network Switching Subsystem (NSS). This architecture must deliver carrier-grade mobility, scalability, and reliability; while being optimized for efficient roaming, routing and backhauling from remote service areas. In a geographic arena that spans across the globe, classical circuit-switched networks are not cost efficient due to their integrated call control (signaling) and switching architecture. A solution to this may be soft-switching which separates the call control (Media Gateway Controller (MGC)) and switching (Media Gateway (MG)) into separate nodes. This methodology would fundamentally change the way circuit-switched services, such as traditional voice telephony, are handled. For a service provider this enables a much more efficient network, because it allows optimized equipment location for voice termination into other carrier networks. Co-location of media gateways with satellite ground stations enables local termination to the public switched telephone network (PSTN), thus offloading a great deal of the traffic from the backhaul transmission network of the mobile operator. This thesis adopts soft-switching as part of the call routing processes. The thesis considers the problem of transporting voice and signaling from-to the remote service areas, efficient routing and backhaul to the location of most suitable operator’s point of presence. The thesis explores an alternative which uses a packet switched backbone (e.g. IP based) to transport the media as close (geographically) to the dialed party as possible before terminating it at the PSTN network, thus achieving optimal routing of voice and signaling. Considering the aforesaid, the thesis describes a detailed network architecture and an operational system prototype for maritime GSM network deployment, as a befitting and challenging example of remote service area. / När det gäller deras Radio access nät, finns det inte två Mobiloperatörer, som betjänar avlägsna områden, som är lika. Trots olika omständigheter och teknologier, ett väl designat optimerat RAN måste anpassa sig till den existerande nätverks teknologin, både med avseende på äldre befintlig teknologi och på moderna telekomnät, för att kunna skapa bästa möjliga nätverk givet många begränsningar. Det är en missuppfattning i tekniska kretsar att en optimerad IP anpassad RAN arkitektur är mer teoretisk än praktisk. Å andra sidan så är det ovan sagda väldigt beroende på vilken teknologi som har använts. En paket optimerad IP-GSM Radio Access Nätverks (IPGRAN) arkitektur är föreslagen i denna masters uppsats, den baseras på Internet Protokollet (IP) snarare än något egenutvecklat proprietärt protokol för komunikation mellan Basstation (BTS), Basstationscontroller (BSC), och nätets switchade subsystem (NSS). Denna arkitektur måste leverera carrier-grade (operatörs klassad) mobilitet, skalbarhet och tillgänglighet och samtidigt vara optimerat för effektiv roaming, routing och anslutning från avlägsna områden. På ett geografiskt område som sträcker sig runt hela jordklotet är inte klassiska kretskopplade nätverk kostnadseffektiva beroende på deras integrerade signallerings och samtals arkitektur. En bättre arkitektur kan vara en sk “softswitch” lösning som separerar samtalet i en (Media Gateway Controller (MGC)) och signaleringen (Media Gateway (MG)) i separata noder. Denna metod skulle på ett fundamentalt vis ändra det sätt på vilket traditionella kretskopplade tjänster som traditionell telefoni hanteras. För en tjänsteleverantör möjliggör detta ett mycket effektivare nätverk då det möjliggör optimerad utplacering av utrustning för terminering av rösttrafik in i andra operatörers nät. Samlokalisering av media gateways (MG:s) med jordstationer för satellitkommunikation möjliggör lokal anslutning till det allmänna telenätet (PSTN), vilket kraftigt minskar den trafik som behöver transporteras genom operatörens stomnät. Denna mastersuppsats behandlar “softswitching” som en del av metoden att växla och transportera samtalstrafik. Uppsatsen behandlar problemet med att skicka samtalstrafik och signalering från avlägsna områden, effektiv routing och transport av trafiken till den operatör som har den närmaste(alt. mest optimala) anslutningspunkten. Uppsatsen undersöker ett alternativ som använder ett paketförmedlat (IP baserat) transportsätt för att transportera trafiken geografiskt sett så nära den uppringda parten som möjligt innan den termineras i det allmänna telenätet (PSTN) varvid man uppnår optimal växling (alt. routing) av rösttrafik och signalering. I beaktande av ovanstående beskriver uppsatsen en detaljerad nätverksarkitektur och en funktionsduglig systemprototyp för ett maritimt GSM nät som ett utmanande exempel på ett avlägset beläget nät.
212

Flots de liens pour la modélisation d'interactions temporelles et application à l'analyse de trafic IP / Link streams for modelling interactions over time and application to the analysis of ip traffic

Viard, Tiphaine 29 September 2016 (has links)
Les interactions sont partout : il peut s'agir de contacts entre individus, d'emails, d'appels téléphoniques, de trafic IP, d'achats en ligne, d'exécution de code, etc. Les interactions peuvent être dirigées, pondérées, enrichies d'informations supplémentaires, cependant, dans tous les cas, une interaction signifie que deux entités u et v ont interagi du temps b au temps e : par exemple, deux individus u et v se rencontrent du temps b au temps e, deux machines sur un réseau démarrent une session IP du temps b au temps e, deux personnes u et v se téléphonent du temps b au temps e, etc.Dans cette thèse, nous explorons une nouvelle approche visant à modéliser les interactions directement comme des flots de liens, c'est-à-dire des séquences de quadruplets (b,e,u,v) signifiant que u et v ont interagi du temps b au temps e. Nous posons les fondations du formalisme correspondant. Afin de valider notre travail théorique, nous nous concentrons sur l'analyse de trafic IP. Il est en effet crucial pour nous d'effectuer des aller-retours constants entre théorie et pratique : les cas pratiques doivent nourrir notre réflexion théorique, et, en retour, les outils formels doivent être conçus de façon à être appliqués de la manière la plus générale.Nous appliquons notre formalisme à l'analyse de trafic IP, dans le but de valider la pertinence de notre formalisme for l'analyse de trafic IP, ainsi que comme méthodologie de détection d'événements. Nous élaborons une méthode permettant d'identifier des événements recouvrant plusieurs échelles de temps, et l'appliquons à une trace de trafic issue du jeu de données MAWI. / Interactions are everywhere: in the contexts of face-to-face contacts, emails, phone calls, IP traffic, online purchases, running code, and many others. Interactions may be directed, weighted, enriched with supplementary information, yet the baseline remains: in all cases, an interaction means that two entities u and v interact together from time b to time e: for instance, two individuals u and v meet from time b to time e, two machines on a network start an IP session from time b to time e, two persons u and v phone each other from time b to time e, and so on.In this thesis, we explore a new approach consisting in modelling interactions directly as link streams, i.e. series of quadruplets ( b, e, u, v ) meaning that u and v interacted from time b to time e, and we develop the basis of the corresponding formalism. In order to guide and assess this fundamental work, we focus on the analysis of IP traffic. It is particularly important to us that we make both fundamental and applied progress: application cases should feed our theoretical thoughts, and formal tools are designed to have meaning on application cases in the most general way.We apply our framework to the analysis of IP traffic, with the aim of assessing the relevance of link streams for describing IP traffic as well as finding events inside the traffic. We devise a method to identify events at different scales, and apply it to a trace of traffic from the MAWI dataset.
213

Longitudinal Characterization of the IP Allocation of the Major Cloud Providers and Other Popular Service Providers : An analysis of the Internet Plane projects collection / Karaktärisering av IP adresser allokerade till moln- och andra populära tjänstleverantörer

Girma Abera, Hyab, Grikainis, Gasparas January 2022 (has links)
With the growth of the internet and exhaustion of IPv4 addresses, the allocation of IP addresses and routing between autonomous systems is an important factor on what paths are taken on the internet. Paths to different destinations are impacted by different neighbouring autonomous systems and their relations with eachother are important in order to find an optimal route from source to destination. In this thesis we look at a longitudinal change of IP observed on the internet that is owned by large organizations. To achieve this we build tools for extracting and parsing data from a dataset from iPlane where we then compare this to the largest domains and cloud providers. From our results we conclude that large domains and cloud providers are found more often as time has passed and they seem to not peer with eachother. We also find that the routing policies within different autonomous systems varies.
214

Diameter : Next generations AAA protocol / Diameter : Nästa generations AAA protocol

Ventura, Håkan January 2001 (has links)
<p>The need for AAA protocols in the world are increasing and todays most common protocols RADIUS and TACACS+, cannot cope with the fast advances in fields benefiting from the use of AAA protocols. This is why IETF has developed the protocol Diameter as a next generations AAA protocol. The objective of this thesis is to account for the work conducted with Diameter as well as to determine if it is going to become the major AAA protocol of the next generation. In this thesis, I describe what Diameter is, its close integration with the Mobile IP protocol and its other uses. As Diameter is based on RADIUS an introduction to AAA and RADIUS is given in order to comprehend where we are today and where we are going as well as to why. I also compare today’s protocols (RADIUS, TACACS+, Kerberos and COPS) against the next generations AAA protocol Diameter. From this comparison, the Mobile IP integration capabilities and an analysis of the support of the Diameter protocol I have come to the conclusion that Diameter is going to become the major AAA protocol of the next generation.</p>
215

Diseño de un sistema de videovigilancia IP para la Autoridad Nacional del Servicio Civil

Perlacios Gastelú, Antonio, Rivera Cardenas, Juan Ramón January 2015 (has links)
El objetivo de la presente tesina es el estudio técnico para la Autoridad del Servicio Civil - Lima, orientado a diseñar un sistema de Videovigilancia IP, lo cual es una tecnología de vigilancia visual con las ventajas digitales de las redes de comunicación IP (Internet Protocol), lo cual permite la supervisión local y/o remota de imágenes y audio así como el tratamiento digital de las imágenes. Existe una gama muy amplia de cámaras con diferentes funcionalidades para satisfacer todas las necesidades y presupuestos. El objetivo es diseñar un sistema de Videovigilancia IP, el cual permita vigilar y controlar a todo el personal para así poder disminuir las pérdidas de los activos. 1. Diseñar un sistema de Videovigilancia IP para una supervisión continua de los datos enviados por la cámara IP. 2. Diseñar la red lógica y física de la Videovigilancia IP. 3. Propuesta de un plan de capacitación de personal involucrado en el manejo de los equipos de Videovigilancia IP, alcanzados en este trabajo. The aim of this thesis is the technical study for the Civil Service Authority - Lima, guied at designing an IP video-surveillance system, which is a visual surveillance technology with digital advantages of IP communication networks (Internet Protocol), allowing the local supervision and/or remote images and audio; and the digital image processing. There is a wide range of cameras with different features to satisfy all needs and budgets. The goal is to design an IP video-surveillance system, which allows monitoring and controlling all personnel in order to reduce losses of assets. 1. Design an IP video-surveillance system for continuous monitoring of the data sent by the IP camera. 2. Design the logical and physical network of video-surveillance IP. 3. Proposal of a training plan for staff involved in the management of IP video-surveillance equipment, made in this work.
216

Avaliação de desempenho de algoritmos de compressão de cabeçalho cooperativos para aplicações VoIP em redes sem fio / Performance evaluation of cooperative header compression algorithms for voip applications in wireless networks

Abinader Junior, Fuad Mousse 13 April 2006 (has links)
Made available in DSpace on 2015-04-11T14:03:03Z (GMT). No. of bitstreams: 1 Fuad M Abinader Junior.pdf: 1012469 bytes, checksum: 83006b70c65e7b5ac0b070b259981f64 (MD5) Previous issue date: 2006-04-13 / The current wireless networks development scenario indicates that mobile VoIP applications are increasing their appeal among consumers, which creates an increasing demand for bandwidth consuption. However, bandwidth availability for VoIP applications is restricted by phisical and regulatory means. Header compression algorithms are one of the most used bandwidth optimization techniques for VoIP applications in wireless networks. This dissertation presents a performance evaluation of cooperative header compression algoritms for VoIP applications in wireless networks. The results indicate that the use of the single-channel cooperative approach leads to excelent results in terms of bandwidth optimization alied with robust context update. Also, the results indicate that the multi-channel cooperative approach has serious issues regarding parallel asyncrhonous VoIP connections. / O cenário atual do desenvolvimento das redes sem fio indica que o apelo por aplicações VoIP móveis está crescendo entre os consumidores, o que gera uma demanda cada vez maior de consumo de largura de banda. No entanto, a disponibilidade de largura de banda para aplicações VoIP é limitada tanto pelo meio físico quanto por regulamentações governamentais. O uso de algoritmos de compressão de cabeçalho é uma das técnicas mais usadas para otimização de largura de banda para aplicações VoIP em redes sem fio. Esta dissertação apresenta uma avaliação de desempenho de algoritmos de compressão de cabeçalhos cooperativos para aplicações VoIP em redes sem fio. Os resultados indicam que a utilização do algoritmo cooperativo mono-canal leva a excelentes resultados em termos de otimização de largura de banda com a manutenção das atualizações de contexto. Além disso, os resultados indicam que o uso do algoritmo cooperativo multi-canal possui sérias restrições quando utilizado em conjunto com conexões VoIP paralelas e assíncronas.
217

Diameter : Next generations AAA protocol / Diameter : Nästa generations AAA protocol

Ventura, Håkan January 2001 (has links)
The need for AAA protocols in the world are increasing and todays most common protocols RADIUS and TACACS+, cannot cope with the fast advances in fields benefiting from the use of AAA protocols. This is why IETF has developed the protocol Diameter as a next generations AAA protocol. The objective of this thesis is to account for the work conducted with Diameter as well as to determine if it is going to become the major AAA protocol of the next generation. In this thesis, I describe what Diameter is, its close integration with the Mobile IP protocol and its other uses. As Diameter is based on RADIUS an introduction to AAA and RADIUS is given in order to comprehend where we are today and where we are going as well as to why. I also compare today’s protocols (RADIUS, TACACS+, Kerberos and COPS) against the next generations AAA protocol Diameter. From this comparison, the Mobile IP integration capabilities and an analysis of the support of the Diameter protocol I have come to the conclusion that Diameter is going to become the major AAA protocol of the next generation.
218

Anonymizace PCAP souborů / Anonymization of PCAP Files

Navrátil, Petr January 2020 (has links)
This diploma thesis deals with the design and implementation of an application suitable for the anonymization of PCAP files. The thesis presents TCP/IP model and for each layer highlights attributes that can be used to identify real people or organizations. Some of the anonymization methods suitable to modify highlighted attributes and sensitive data are described. The implemented application uses TShark tool to parse byte data of PCAP format to JSON format that is used in the application. TShark supports lots of network protocols which allows the application to anonymize various attributes.  Anonymization process is controlled by anonymization politics that can be customized by adding new attributes or anonymization methods.
219

AN IP-BASED RECORDING SYSTEM

Roach, John, Hildin, John 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / Traditionally, acquired instrumentation data on a non-destructive test article is recorded to a nonvolatile memory recorder. The data acquisition system usually samples and formats its inputs before transmitting the data to the recorder (also known in this paper as a data sink) via a PCM serial data stream (i.e., clock and data). In a network-based data acquisition architecture, the inclusion of an IP-based recorder adds a new dimension to the data acquisition process. Any IP network inherently allows for the bi-directional exchange of data. In this environment, the IPbased recorder can be treated as both a data sink for parameter recording and a data source for parameter extraction, data rate statistics, and recorder status reporting. The network model recasts the data recorder’s function as a file server to which multiple clients could be simultaneously requesting services. Those clients that represent the data acquisition nodes are requesting storage of their acquired parameters. Clients, such as transmitters or test engineers, are requesting access to archived data or status information for further processing. This paper presents the advantages of using an IP-based recorder in a network-based data acquisition system. The availability of an IP interface along with the intelligence built into the recorder expands its capabilities beyond that of a conventional PCM recorder. These capabilities include real-time health monitoring, support for the Simple Network Management Protocol (SNMP), data mining, reporting of real-time performance and network statistics.
220

A SYSTEM APPROACH TO A NETWORK CENTRIC AIRBORNE DATA ACQUISITION SYSTEM

Berdugo, Albert, Hildin, John 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / Airborne data acquisition systems have changed very little over the years. Their growth has primarily been in the area of digital filtering and the acquisition of new avionic busses. Communication between data acquisition units operating as a system still employs Time Division Multiplexing scheme. These schemes utilize command and data busses like CAIS and PCM. Although this approach is highly efficient, it has many drawbacks. These drawbacks have resulted in rigid system architecture, system bandwidth limitations, highly specialized recorders to acquire unique avionic busses that would otherwise overwhelm the system bandwidth, and unidirectional flow of data and control. This paper describes a network centric data acquisition system that is Ethernet based. Although Ethernet is known as an asynchronous bus, the paper will describe a deterministic time distribution over the bus per IEEE-1588 that allows the use of a packet network for airborne data acquisition. The acquisition unit within the network system is defined by its MIB (Management Information Base) and operates as a data source unit. Other network components may operate as a data sink unit, such as recorders, or as a data source and sink. The role of different units in the network system will be evaluated. The paper will also describe network gateways that allow the use of traditional PCM systems with a network-based system.

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