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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.
1

Determining Optimal Fibre-optic Network Architecture using Bandwidth Forecast, Competitve Market, and Infrastructure-efficienct Models used to Study Last Mile Economics

Saeed, Muhammad 20 December 2011 (has links)
The study focuses on building a financial model for a telecommunications carrier to guide it towards profitable network investments. The model shows optimal access-network topography by comparing two broadband delivery techniques over fibre technology. The study is a scenario exploration of how a large telecommunication company deploying fibre will see its investment pay off in a Canadian residential market where cable operators are using competing technology serving the same bandwidth hungry consumers. The comparison is made at the last mile by studying how household densities, bandwidth demand, competition, geographic and deployment considerations affect the economics of fibre technology investment. Case comparisons are made using custom models that extend market forecasts to estimate future bandwidth demand. Market uptake is forecasted using sigmoid curves in an environment where competing and older technologies exist. Sensitivity analyses are performed on each fibre technology to assess venture profitability under different scenarios.
2

Determining Optimal Fibre-optic Network Architecture using Bandwidth Forecast, Competitve Market, and Infrastructure-efficienct Models used to Study Last Mile Economics

Saeed, Muhammad 20 December 2011 (has links)
The study focuses on building a financial model for a telecommunications carrier to guide it towards profitable network investments. The model shows optimal access-network topography by comparing two broadband delivery techniques over fibre technology. The study is a scenario exploration of how a large telecommunication company deploying fibre will see its investment pay off in a Canadian residential market where cable operators are using competing technology serving the same bandwidth hungry consumers. The comparison is made at the last mile by studying how household densities, bandwidth demand, competition, geographic and deployment considerations affect the economics of fibre technology investment. Case comparisons are made using custom models that extend market forecasts to estimate future bandwidth demand. Market uptake is forecasted using sigmoid curves in an environment where competing and older technologies exist. Sensitivity analyses are performed on each fibre technology to assess venture profitability under different scenarios.
3

FTTx přístupové infrastruktury / FTTx access networks

Hladký, Miroslav January 2008 (has links)
This graduation thesis addresses questions of deriving benefits from the FTTx optical access network. This project is divided into four main subject surveys. First part contains familiarization with individual architecture of FTTx network, topology of network and the use of components in these access networks. Second part shows how ideal optical access network is for distribution of modern multimedia services which pose great demand on the width of transmission band. It also shows success and trend growth of integration of the optical network into access segment in the Czech Republic and the rest of the world. The choice of right proposal and follow-on project of FTTx optical access network in assigned location is described in part three. It also compares investment costs needed for implementation of these proposals. Final part of this project shows financial budget and return of investments of a proposed access network. It also includes a contemplation of optical access network’s development.
4

Parametry sítí FTTx / Parameters of FTTx Networks

Münster, Petr January 2014 (has links)
This thesis examines parameters of FTTx networks and possibilities for increases in limit values of some selected parameters. The first and second chapters describe the necessary theory for understanding the outcomes presented in the rest part of the work. In the practical part of this thesis, analysis of the condition of the optical fibers in the Czech Republic is provided. Based on the results, the impact of the polarization mode dispersion on optical access networks was assessed. The next part of this thesis is focused on the active optical networks design, depending on the cost of implementation and operating costs. The main limiting parameters of the current passive optical networks are bandwidth and insertion loss of the optical distribution network. To increase the bandwidth a system based on optical time-division multiplexing with a bandwidth of 1.28 Tbit/s has been designed and created. By using polarization division multiplexing technique the system is also more tolerant to dispersions. In the last part of this thesis, a remote amplification system was verified by measurement and simulation. Based on the obtained results, a NG-PON2 network with a functional remote amplification system with a gain of more than 10 dB has been designed in the OptiSystem software.
5

Μοντέλο για τεχνο-οικονομική ανάλυση δικτύων οπτικών ινών

Σπυρώνης, Ιωάννης 21 December 2011 (has links)
Η ραγδαία αύξηση της κίνησης στο διαδίκτυο έχει δημιουργήσει ολοένα και μεγαλύτερη ζήτηση για ευρυζωνικά δίκτυα. Τα δίκτυα οπτικών ινών είναι μια κατηγορία ευρυζωνικών δικτύων που υπόσχονται ευέλικτες και ικανές να υποστηρίξουν πληθώρα υπηρεσιών, δικτυακές επικοινωνίες με θεωρητικά απεριόριστη χωρητικότητα. Πλέον, τα οπτικά δίκτυα δεν καλύπτουν μόνο το βασικό δίκτυο κορμού, αλλά εκτείνονται μέχρι τον τοπικό βρόχο αλλά και την κατοικία των τελικών χρηστών. Έτσι, τα οπτικά δίκτυα πρόσβασης FTTx και οι διάφορες τεχνολογίες τους όπως PON, AON και Home Run εφαρμόζονται στις δικτυακές υποδομές που αναπτύσσονται από το κεντρικό γραφείο του δικτύου της περιοχής κάλυψης μέχρι το συνδρομητή. Η παρούσα εργασία μελετά τεχνικά θέματα που αφορούν κυρίως το εξωτερικό τμήμα των FTTH δικτύων, δηλαδή των FTTx μέχρι το σπίτι, όπως η υποδομή σωληνώσεων, καλωδίων, τάφρων, φρεατίων, κ.λπ. Τα στοιχεία αυτά προκαλούν τα υψηλότερα κόστη στο δίκτυο πρόσβασης (κόστη CAPEX) και για αυτό το λόγο δίνεται ιδιαίτερη έμφαση σε αυτά. Εκτός από αυτά, υπάρχουν και τα OPEX κόστη, που δεν ασχολούμαστε εκτενώς στα πλαίσια της εργασίας. Επίσης, στην εργασία παρουσιάζεται μια μεθοδολογία για την επιχειρησιακή μελέτη σε δίκτυα FTTH, στην οποία παρουσιάζονται τα στάδια για την οικονομική μελέτη ανάπτυξης των δικτύων. Ο βασικός στόχος της εργασίας είναι η υλοποίηση ενός μοντέλου που αυτοματοποιεί τη διαδικασία σχεδιασμού των υπόγειων FTTH δικτύων πρόσβασης, που χρησιμοποιούν την τεχνολογία Home Run. Το μοντέλο χρησιμοποιεί στοιχεία από γεωγραφικό σύστημα πληροφοριών GIS για το σχεδιασμό του δικτύου, κάνει τους κατάλληλους υπολογισμούς στοιχείων υποδομών με βάση αλγορίθμους και προδιαγραφές και στο τέλος με είσοδο τους πίνακες κόστους των στοιχείων δίνει τις δαπάνες για την ανάπτυξη των υποδομών. Πριν από την ανάπτυξη του μοντέλου, περιγράφονται απλά θεωρητικά γεωμετρικά μοντέλα που μπορούν να απεικονίσουν ένα υπόγειο και εναέριο FTTH δίκτυο. Το μοντέλο εκτελείται σε τρεις περιοχές της Αττικής, που έχουν διαφορετικές πυκνότητες κτιρίων και νοικοκυριών με σκοπό τον ακριβή προσδιορισμό των τελικών κοστών ανά περιοχή. Επιπλέον, μπορούν να υπολογιστούν τα κόστη ανά νοικοκυριό, κτίριο, μονάδα μήκους των τάφρων και γενικά υπόγειων υποδομών. Η αποτύπωση του εξωτερικού δικτύου των περιοχών, των στοιχείων υποδομών, των εξοπλισμών και των τελικών δαπανών τους γίνεται με πλήρως αυτοματοποιημένο τρόπο. / The rapid growth of Internet traffic has created increasing demand for broadband networks. Fiber optic networks are a category of broadband networks that promise flexible and capable for supporting various services, network communications with limitless capacity. Plus, the optical networks do not only cover the core backbone network, but extend to the local loop and the households of end users. Thus, FTTx optical access networks and their various technologies such as PON, AON, and Home Run are implemented in the network infrastructure, which is developed from the central office of the coverage area network to the subscriber. This diploma thesis examines the technical issues related mainly to the outside plant of FTTH networks (FTTx up to the household), such as infrastructure ducts, cables, trenches, holes, etc. These elements rise to higher costs in the access network (CAPEX costs) and for this reason, special emphasis is placed on them. Apart from these, there are OPEX costs. Also, the thesis presents a methodology for the business study of FTTH networks, which shows the stages to study for the economic development of networks. The main aim of this work is to implement a model that automates the design of underground FTTH access networks, that use Home Run technology. The model uses data from Geographical Information System (GIS) for network design, makes the appropriate calculations, based on data infrastructure algorithms and specifications and in the end returns the total costs for infrastructure development based on material cost tables. Before the development of the model, there are descriptions of simple geometric models that can represent an underground and aerial FTTH network. The model runs on three areas of Attica, that have different densities of buildings and households in order to accurately determine the final cost per area. Moreover, they can calculate the cost per household, building, length unit of trenches and other underground infrastructure. The representation of the external network, elements, data infrastructure, equipment and final expenditure is fully automated.
6

Dynamic assignment protocols for multi-wavelength gigabit-PONs

Gliwan, A. January 2011 (has links)
The research initiatives addressed in this thesis are geared towards improving the performance of passive optical networks through the development of advanced dynamic bandwidth allocation protocols. In particular, the aim of the research undertaken is to enhance the quality of service offered by standard passive optical networks with reduced network costs. To that extent, a dynamic multi-wavelength protocol has been developed to increase the network upstream bandwidth and introduce multiple service levels to a fibre to the home-based giga-bit passive optical network. Simulation results have confirmed the reduction of the mean packet delay by adjusting the ITU-T standard G984 giga-bit passive optical network frame format by means of the introduction of extended wavelength band overlay based on the ITU-T Coarse- Wavelength Division Multiplexing grid to support the multi-wavelength functionality. To evaluate the multi-wavelength upstream operation of the newly implemented models in OPNET, 2-dimensional Dynamic Bandwidth Allocation algorithms have been introduced to manage the network resources in both the time and wavelength domains. Furthermore, the enhanced traffic allocation among the supported wavelengths in new protocol confirmed a performance improvement in the network total capacity and the mean packet delay, which demonstrates the network reliability and improves the quality of the provided service according to the subscriber service level agreement, with a minimum guaranteed bandwidth of 100 Mbit/s to fulfil applications and associated bandwidth requirements for the next generation access network.
7

Στρατηγικές και πολιτικές για την ανάπτυξη δικτύων FTTx στις Ηνωμένες Πολιτείες της Αμερικής

Νικολόπουλος, Νικόλαος 21 December 2011 (has links)
H ευρυζωνικότητα δεν είναι μια στενή έννοια αλλά ένα δυναμικό πλαίσιο που αγγίζει ένα ευρύ φάσμα τεχνολογιών, υπηρεσιών και πολιτικοοικονομικών θεμάτων. Συνοπτικά θα λέγαμε ότι η ευρυζωνικότητα χαρακτηρίζει ένα περιβάλλον το οποίο συνίσταται: • Μια δικτυακή υποδομή που έχει τη δυνατότητα να αναβαθμίζεται συνεχώς με μικρό κόστος για να υποστηρίζει τις εκάστοτε ανάγκες των εφαρμογών σε εύρος ζώνης και διαθεσιμότητα • Γρήγορες, συνεχείς και με χαμηλό κόστος συνδέσεις χρηστών στην υποδομή αυτή για τις οποίες δεν τίθενται εγγενείς περιορισμοί που αφορούν τον τύπο τερματικού εξοπλισμού και συστημάτων μετάδοσης • Την ελευθερία επιλογής από το χρήστη της τεχνολογίας και του είδους της σύνδεσης, των υπηρεσιών και εφαρμογών και την δυνατότητα συμμετοχής στην παραγωγή περιεχομένου • Το κατάλληλο θεσμικό και νομικό πλαίσιο για την ενίσχυση της καινοτομίας και του ανταγωνισμού. Όσο αναφορά τις υποδομές και τις τεχνολογίες που χρησιμοποιούνται ευρέως στην σύγχρονη εποχή αυτές διαφοροποιούνται σε ενσύρματες και ασύρματες, και από εκεί και πέρα ποικίλουν. Χαρακτηριστικά αναφέρουμε την χρήση των καναλιών της καλωδιακής τηλεόρασης, των καλωδίων του ρεύματος, της οπτικής ίνας καθώς και την χρήση του wi-fi, του WiMAX και των δικτύων κινητής τηλεφωνίας. Θα κάνουμε μια πιο εκτενής ανάλυση της τεχνολογίας της οπτικής ίνας, οποία αποτελεί την βασικότερη υποδομή ενσύρματης δικτύωσης πλέον, περιγράφοντας τα χαρακτηριστικά της καθώς και τους διάφορους τρόπους δικτύωσης που συναντάμε σήμερα, κάνοντας ιδιαίτερη αναφορά στις τεχνολογίες FTTx. Η ανταγωνιστικότητα ενός κράτους στο νέο αυτό περιβάλλον υψηλής τεχνολογίας και ψηφιακής σύγκλισης, συσχετίζεται έντονα με την ύπαρξη προηγμένων δικτυακών υποδομών υψηλής ποιότητας, χωρητικότητας και απόδοσης, ορθολογικά ανεπτυγμένων και κοστολογημένων, οι οποίες προσφέρουν εύκολη, ασφαλή και αδιάλειπτη πρόσβαση στο διεθνές «ηλεκτρονικό πλέγμα» της γνώσης και του εμπορίου, με προσιτά τιμολόγια χωρίς τεχνητούς αποκλεισμούς. Παρά όμως την σχετικά γρήγορη διάχυση της ευρυζωνικότητας, προς το παρόν όλα τα κράτη είναι στα αρχικά βήματα στην εξάπλωση της. Ο ανταγωνισμός στην αγορά έχει παίξει μεγάλο ρόλο στην ανάπτυξη της ευρυζωνικότητας, δεν φαίνεται όμως να είναι αρκετός για την διασφάλιση της γρήγορης εφαρμογής της. Για το λόγο αυτό παγκοσμίως οι κυβερνήσεις διερευνούν και εφαρμόζουν τρόπους για την προώθηση των ευρυζωνικών υποδομών και των υπηρεσιών, την δημιουργία περιεχομένου και την διασφάλιση της δυνατότητας συμμετοχής στο περιβάλλον αυτό όλων των περιοχών και πολιτών. Καθώς όμως η ευρυζωνικότητα είναι ένα πολυσύνθετο θέμα, δεν φαίνεται να έχουν βρεθεί ευρέως αποδεκτές και ακολουθούμενες βέλτιστες πρακτικές. Αντίθετα κάθε κράτος ακολουθεί τις δικές του πρωτοβουλίες με βάση το θεσμικό του πλαίσιο, την πολιτική και την κουλτούρα του, τις οικονομικές και κοινωνικές συνθήκες που επικρατούν. Στα πλαίσια αυτής της εργασίας θα αναλύσουμε τους στόχους, τα σχέδια, τις πολιτικές και τις στρατηγικές των Ηνωμένων Πολιτειών της Αμερικής για όλα αυτά που μόλις αναφέρθηκαν. Θα φανούν οι τρόποι με τους ποίους οι Η.Π.Α. σκοπεύουν να αναπτύξουν και να κάνουν προσβάσιμες τις ευρυζωνικές υπηρεσίες στους Αμερικανούς πολίτες, καθώς και τα οφέλη που οι ίδιοι αναμένουν να έχουν από τις υπηρεσίες αυτές σε πολλούς τομείς της καθημερινότητας όπως η εκπαίδευση, η υγεία, η ασφάλεια, η εργασία, η συμμετοχή στα κοινά. / Broadband is not a limited sense, but a dynamic framework that touches a broad range of technologies, services and political and economical issues. Synoptically the broadband features an environment that consists of the following: • A Web-based infrastructure which can be upgraded continuously with low cost due to support the needs of applications to bandwidth and the availability. • Fast, continuous and low cost of user connections to this infrastructure for which there are inherent limitations to the type of terminal equipment and transmission systems. • The user has the option of the technology and type of connection, services and applications and the ability to participate in content production. • The appropriate institutional and legal frame for fostering innovation and competition. The infrastructure and technologies which widely used in modern times are various, and they are divided into wired and wireless. In this point it should be mentioned the use of channels of cable television, cable current, the optical fiber and the use of Wi-Fi, the WiMAX and cellular networks. An extensive analysis of the optical fiber technology, which is the most basic infrastructure, where is now known as wired networking, with description of its characteristics and the various ways of networking in the modern world , with particular reference to technologies FTTx will be followed. The competitiveness of a country in this new environment of high technology and digital convergence correlates strongly with the presence of advanced network infrastructure quality, capacity and performance, rationally developed and costed, which offer easy, secure and uninterrupted access to the international "electronic network" of knowledge and commerce, with affordable rates without artificial exclusions. Despite the relatively rapid diffusion of broadband, currently all States are in the early steps in the spread. The market competition has strongly affected the development of broadband, but it is not sufficient to ensure the rapid implementation. For this reason, governments worldwide are investigating and implementing ways to promote broadband infrastructure and services, content creation and ensuring the participation of all regions and citizens in this environment. Due to the broadband is a complex issue, it seems that practises, which will be widely accepted and followed, are not established yet. Contrary each state follows its own initiatives under the institutional frames, policy and culture, economic and social conditions. As part of this thesis, it will analyze the targets, plans, policies and strategies of the United States of America for all those which were just mentioned. Providing the means that U.S. intend to develop in order to make accessible broadband services to all American citizens, and the expected benefits applying in many areas of daily life, such as education, health, safety, labor and citizenship, from the use of these services.
8

FTTX-Analysverktyg anpassat för Telias nät / FTTX-Analysis tool designed for Telia's network

Brännback, Andreas January 2018 (has links)
Ett verktyg har utvecklats i programmeringsspråket Python, som analyserar status för uppkopplingar hos Fibre to the X (FTTX)-kunder i Telias nät. Systemet består av en moduluppdelad struktur, där alla analysfunktioner av samhörande typer är uppbyggda i egna moduler. Alla moduler lagras som individuella kodfiler. Systemet är designat för att enkelt kunna vidareutvecklas genom att tillägga fler analysmoduler i framtida projekt. För att utföra en analys på en specifik kund, hämtar systemet tekniska dataparametrar via den switch som kunden sitter uppkopplad mot. Dessa parametrar jämförs därefter med förbestämda värden för att hitta avvikelser. Simple network management protocol (SNMP) och Telnet är de primära protokollen som används för att hämta relevant data. Systemet har enbart Hypertext Transfer Protocol (HTTP) som input och output. Resultatet av en analys, redovisas som Extensible Markup Language (XML) mot den server som ursprungligen ställde förfrågan till att starta en analys. XML svaret innehåller både tekniska dataparametrar kring kundens uppkoppling samt ett analyssvar baserat på dessa tekniska parametrar. Utförligheten i svaret på en utförd analys varierar en aning beroende på switchtypen kunden sitter uppkopplad mot. Switchar av äldre hårdvarutyper presenterar generellt sett mindre kundportsdata jämfört med modernare varianter. Mindre kundportsdata leder till sämre utförlighet i analyssvaret. Därför lämpar sig detta analysverktyg bättre mot de modernare switcharna som finns i Telias nät. / A tool for analyzing the status of Fiber to the X (FTTX) customers in Telia’s network has been programmed in the Python programming language. The system consists of a module divided structure where analysis functions of similar types are bundled into module files. The system is designed to be easily further developed by adding more analysis modules in future projects. To perform an analysis on a specific customer, the system retrieves technical data parameters from the switch which the customer is connected to, and compares these parameters against predetermined values to find deviations. Simple Network Management Protocol (SNMP) and Telnet are the primary protocols used to retrieve data. Hypertext Transfer Protocol (HTTP) is used to transfer data as system input and output. The result of an analysis is sent as Extensible Markup Language (XML) back to the server that originally requested the start of an analysis. The XML reply contains technical data parameters describing the customer’s connection status and an analytical response based on these technical parameters. The amount of data presented in the XML response varies slightly depending on the type of switch the customer is connected to. Switches of older hardware types generally presents less customer port data compared to more modern switches. Less customer port data leads to poor detail in the analytical response, and therefore, this analysis tool is better suited to the modern switches found in Telia's network.
9

Síť FTTx / FTTx networks

Hradílek, Pavel January 2009 (has links)
The aim of this thesis is to clarify the issue of optical access networks, and to acquaint the reader with problems of their design and implementation. The introductory chapter describes the technologies and topologies, which are the most experienced in dealing with optical access network. There are a comparison of their basic parameters and limiting factors. Another part of the work is dedicated to progressive methods of construction such as microtubes and solution using the hanging cables, which due to the efficiency of construction, rapidity, economic and facilitate implementation. In conclusion the theoretical part there is issues of measurement. It describes a Optical Loss Test Set, OTDR method and method of measuring dispersion. Increasing demands on the capacity of the transmission paths, and their quality are caused of monitoring optical access networks, which can evaluate the failure on a route, target problems and inform service. The practical part compares EPON and GPON. In program OptiSystem was created model which these technologies are evaluated in terms of performance parameters, noise, jitter and eye diagram quality. The common feature of technology is transmission TDM frames, where EPON uses Ethernet and GPON technologies ATM. The outcome of simulation don´t show which technology is better, but result shows the conditions of the proposal of these technologies. At the end of work there are created several models for solving the optical access network with pricing per user. The most developed technology is FTTB in urban areas, when transmission in last mile uses copper circuit. This solution causing a rapid return on investment. Other technologies such as point-to-point FTTH or PON are implemented as individual proposals. Each of these solutions has advantages and disadvantages, so each project is unique and the solution is dependent on the project site and the requirements of customers.
10

Návrh optické přístupové sítě FTTx / Design of FTTx optical access network

Münster, Petr January 2010 (has links)
The aim of this work is an overview of the proposal for FTTx Optical Access Networks. In the introductory chapter written about the optical fiber and the transmission. Furthermore, as already discussed various options with regard to the implementation instead of the end of optical fiber - FTTN, FTTC, FTTP, FTTB, FTTH and standards, which are used to build fiber optic networks. The next chapter is an overview of the network elements that are in different layers reference model ISO / OSI used. The final theoretical chapter is devoted to progressive technologies for the construction of optical access networks, which has recently been used. Concepts are explained as HDPE pipe, microtubing or self-supporting cables. The practical part design model, passive optical networks in the area Slavičín, located in the Zlín region. FTTB architecture was chosen, where for each connection object is used in the existing copper lines. The proposed route will use a standard technology GEPON Wavelength division WDM, so to connect the individual buildings will be used only one thread. Realization of optical networking technology will be excavation. The optical cables and optical fiber bundles are protected by HDPE pipes stored in the bed of sand. For the optical signal split into multiple lines will be used by an optical splitter 1 / 16, located in an outdoor cabinet optic pathway. The distribution of signals for the settlement will take care Alloptic central station, which is optimized for the transmission of Triple Play services. On the basis of the proposal is to created a financial analysis that shows the return on the project. An important part of the network is also monitoring the network. The last part of this work therefore deals with the possibilities of monitoring networks in order to continuously monitor the network, in order to prevent any disturbances or quickly respond to network problems.

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