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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.
11

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.
12

Utredning av VPLS i stadsnät / Investigation of VPLS in a Metropolitan Area Network

Pettersson, Kristoffer, Sales, Robert January 2007 (has links)
<p>Jönköping Energi AB (JEAB) is a local energy supplier for the county of Jönköping. JEAB also maintain the local Metropolitan Area Network (MAN). They have recently installed GPON in a portion of their network and have connected it to the MAN via an Extreme switch.</p><p>However JEAB would prefer to use Cisco equipment instead of Extreme since the MAN comprises of Cisco hardware. They require a solution to connect GPON to the MAN with a recently purchased line card (Cisco 7600 ES20) which can be installed in a Cisco 6500 Catalyst switch. There is also a possible solution with an Alcatel-Lucent 7450 ESS-1 switch. The proposed solution is to use Virtual Private LAN Service (VPLS), though the exact implementation required is unknown. Additionally JEAB have asked for research into GPON and VPLS in order to improve their understanding of both techniques. This would be of benefit to them both now and in the future.</p><p>In order to achieve the stated objectives the following questions are raised:</p><p>• How does GPON work?</p><p>• How does VPLS work?</p><p>• How can GPON be connected to the MAN via Cisco Systems 6500 Catalyst switch/7600 Router?</p><p>• How can GPON be connected to the MAN via Alcatel-Lucents 7450 ESS-1?</p><p>The research into GPON and VPLS provides the required background knowledge in order to investigate how GPON can be connected to the MAN. The main body of the work is to analyse the requirements of the company and build a configuration which satisfies them. The desired implementation via Cisco Systems solution was deemed unsuitable due to a feature of DHCP option 82 which did not function as required. The focus then turned to Alcatel-Lucents solution.</p><p>The resulting solution uses a part of VPLS via Alcatel-Lucents 7450 ESS-1. All the key elements are included, including hiding customer VLANs from the ISP and per-service QoS bandwidth management.</p><p>The conclusion is that whilst using Alcatel-Lucents solution means a deviation from the all-Cisco implementation that had been planned; the benefit of including all the desired functionality outweighs the mixing of manufacturers.</p><p>The techniques of GPON and VPLS are extremely versatile and can be used in a variety of networks. Therefore there is scope for further research into how these two techniques can be used together in other types of MAN.</p>
13

Laser Driver Design in 0.18 um CMOS Technology

O'FARRELL, Michael 24 September 2010 (has links)
This thesis presents the design and analysis of two high speed analog laser driver stages (LDS) for use in a passive optical network (PON) upstream burst-mode transmitter (BM-Tx) using low cost complementary metal oxide semiconductors (CMOS) technology. The maturation of CMOS technology has lead to aggressive scaling of device sizes which has made it an increasingly attractive technology for high speed analog design. CMOS provides high levels of integration as it is the industry standard for digital circuits, analog and digital systems can share one substrate reducing costs. Additionally CMOS is a more cost effective solution than traditional expensive high speed analog substrates. A 2.5 Gbps LDS fabricated in 0.18 um CMOS technology is presented. The LDS uses a two stage per-amplifier. Stage one consists of a cascode differential pair with a source follower voltage buffer, while stage two consists of a shunt inductively peaked differential pair using active inductors. A differential pair composed of large transistors is used in an open drain configuration for the output stage. Measurements of S-parameters are presented which accurately agree with simulations. Electrical eye diagram measurements are presented which demonstrate the LDS is able to provide a modulation current of 14.6-58 mA. 10%-90% approximate rise/fall times of 230/260 ps was obtained for a modulation current of 58 mA. Power consumption of the core was determined to be 68.5 mW, while the chip consumed an area of 0.8 mm x 0.7 mm including pads. A 10 Gbps LDS fabricated in 0.18 um CMOS technology is also presented. The LDS uses a cascode differential pair for the output stage. The per-amplifier for this design consists of a differential pair and utilizes spiral inductors for series inductive peaking between the per-amplifier and output stage. Measurements of S-parameters are presented which accurately agree with simulations. Electrical eye diagram measurements are presented which demonstrate the LDS is able to provide a modulation current of 22.6-62 mA. 10%-90% rise/fall time of 87 ps and 75 ps are respectively obtained while operating at maximum modulation current. The core of the LDS consumes a power of 287 mW, while the chip consumed an area of 0.79 mm x 0.7mm. The measured electrical eye diagrams for the 2.5 Gbps and the 10 Gbps meet the timing requirements for the GPON standard. Further work is needed to investigate whether or not the timing requirements would still be met once the CMOS chips are integrated with commercial laser diodes. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-09-24 10:43:33.418
14

Utredning av VPLS i stadsnät / Investigation of VPLS in a Metropolitan Area Network

Pettersson, Kristoffer, Sales, Robert January 2007 (has links)
Jönköping Energi AB (JEAB) is a local energy supplier for the county of Jönköping. JEAB also maintain the local Metropolitan Area Network (MAN). They have recently installed GPON in a portion of their network and have connected it to the MAN via an Extreme switch. However JEAB would prefer to use Cisco equipment instead of Extreme since the MAN comprises of Cisco hardware. They require a solution to connect GPON to the MAN with a recently purchased line card (Cisco 7600 ES20) which can be installed in a Cisco 6500 Catalyst switch. There is also a possible solution with an Alcatel-Lucent 7450 ESS-1 switch. The proposed solution is to use Virtual Private LAN Service (VPLS), though the exact implementation required is unknown. Additionally JEAB have asked for research into GPON and VPLS in order to improve their understanding of both techniques. This would be of benefit to them both now and in the future. In order to achieve the stated objectives the following questions are raised: • How does GPON work? • How does VPLS work? • How can GPON be connected to the MAN via Cisco Systems 6500 Catalyst switch/7600 Router? • How can GPON be connected to the MAN via Alcatel-Lucents 7450 ESS-1? The research into GPON and VPLS provides the required background knowledge in order to investigate how GPON can be connected to the MAN. The main body of the work is to analyse the requirements of the company and build a configuration which satisfies them. The desired implementation via Cisco Systems solution was deemed unsuitable due to a feature of DHCP option 82 which did not function as required. The focus then turned to Alcatel-Lucents solution. The resulting solution uses a part of VPLS via Alcatel-Lucents 7450 ESS-1. All the key elements are included, including hiding customer VLANs from the ISP and per-service QoS bandwidth management. The conclusion is that whilst using Alcatel-Lucents solution means a deviation from the all-Cisco implementation that had been planned; the benefit of including all the desired functionality outweighs the mixing of manufacturers. The techniques of GPON and VPLS are extremely versatile and can be used in a variety of networks. Therefore there is scope for further research into how these two techniques can be used together in other types of MAN.
15

Analýza gigabitové pasivní optické sítě / Gigabit Passive Optical Network Analysis

Mižička, Vladislav January 2018 (has links)
Cílem této práce je konfigurace vysokorychlostního paketového analyzátoru Endace, konfigurace zařízení gigabitové pasivní optické sítě (GPON) a následná analýza zachycených dat. Práce by měla být soustředěna zejména na možnost detekce provozních dat jednotky GPON. V teoretické části je stručně popsaný paketový analyzátor a jeho možnosti, dále také jednotka GPON a možnosti zapojení s analyzátorem k detekci provozu. V praktické části, zařízení jsou nakonfigurovaná a zachycená data analyzovaná.. Aplikace vyvinutá s pomocí jazyka Python podporuje příjem a zpracování dat. Výstup analýzy by měl být v rámci možností co nejpodrobnější s popisem významu jednotlivých položek.
16

Multidimenzionální analýza dat a zpracování analytického zobrazení / Multidimensional Data Analysis and Analytic View Processing

Foltýnová, Veronika January 2018 (has links)
This thesis deals with the analysis and display of multidimensional data. In the theoretical part, the issue of data mining, its tasks and techniques, and a brief explanation of the terms Business Intelligence and data warehouse are presented. The issue of databases is also described in this thesis. Subsequently, the options for displaying multidimensional data are described. At the end of the theoretical part is briefly explained the problems of optical networks and especially the terms Gigabit passive optical network and its frame, because the data from the frames of this network will be displayed by an application. In the practical part, you can find creating a source database and an application to create a OLAP cube and display multidimensional data. This application is based on the theoretical knowledge of multidimensional databases and OLAP technology.
17

Návrh a implementace rozhraní pro zpracování rámců xPON / Design and implementation of xPON frame processing interface

Vais, Zdeněk January 2020 (has links)
This thesis focuses on system for persistence of GPON communication. Theoretical part deals with problems of GPON and NG-PON optical networks, NoSQL database systems and MongoDB database. Practical part contains design of a database schema for MongoDB database and source code in programming languages Python and C# for working with this database. The thesis is finalized by performance testing, proving that the database design and source code implementation is capable of handling real world traffic.
18

Webová aplikace pro monitoring optické sítě / Web application tool for optical network monitoring

Rýdl, Pavel January 2021 (has links)
The problematics of gigabit optical networks as well as web technologies suitable for a web tool implementation were studied within this thesis. An experimental web application for monitoring GPON frames is developed based on the proposed system architecture. The frontend is implemented using ReactJS and the Tornado web framework is used for backend implementation. Data for analysis are read from the stream using the Kafka platform.
19

Software hlášení bezpečnostních incidentů v GPON síti / GPON network security incident reporting software

Kupka, Ondřej January 2021 (has links)
This thesis focuses on development of software for security incident reporting from GPON networks. The theoretical part introduces the principles of GPON and provides an introduction to security incidents. The practical part is focused on the selection of suitable open-source systems and the design of an application in Python for the creation of alerts. The output of the work is the deployment of TheHive, Cortex and MISP systems and the creation of an application enabling the creation of various types of alerts based on prepared template. The thesis is finalized by a detailed description of deployment, custom configuration and testing.
20

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.

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