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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

Integrating IP Protocol Into Optical Networks by Using Software-defined Network (SDN)

Al-Ani, Layth January 2015 (has links)
The Internet, with cloud computing, offers amazing services that require a fast, intelligent, reliable network connection. Current networks, electrical or optical, need to work together to provide the user with a high-quality connection. The IP protocol as Layer 3 and an optical network as Layer 2 need to talk to each other and help each other instead of working separately. Therefore, this thesis proposes using software-defined network (SDN) technology for integrating the IP protocol into an optical network to fill the gap between the two layers and to give the network more intelligence and flexibility for new connection requests, choosing the best route, and monitoring the network. A two-layer SDN centralized controller design has been used. The Layer 1 SDN controller is the centralized controller that connects and updates all Layer 2 SDN controllers which control traffic in each domain. New connection requests are processed in the SDN controller and the traffic is forwarded by the optical network. SDN technology and the integration of IP into the optical network promise to enhance network connectivity.
2

Zabezpečený transportní protokol monitorovacích systémů / Secure Transport Protocol for System Monitoring

Halfar, Patrik January 2010 (has links)
This paper deals with NetFlow protocol and analysis of its properties. There is focused on confidentiality and reliability of the data's transfer. All of the solution observe requirements for lower resources of devices, and impossibility of changes in the exporter except defined parameters.
3

Ποιότητα υπηρεσίας σε δίκτυα επόμενης γενιάς : μηχανισμοί για τη χρήση διαφοροποιημένων υπηρεσιών και μεσιτών εύρους ζώνης

Στάμος, Κωνσταντίνος 16 March 2009 (has links)
Κεντρικό αντικείμενο αυτής της Διδακτορικής Διατριβής αποτελεί η μελέτη του συνδυασμού δύο εκ των βασικότερων εξελίξεων που σχετίζονται με το επίπεδο του IP πρωτοκόλλου στο Internet: της δυνατότητας για την παροχή εγγυήσεων ποιότητας (Quality of Service) σε τμήμα της συνολικής κίνησης που διακινείται μέσα από τα IP δίκτυα, καθώς και της ανάγκης αναβάθμισης του IPv4 πρωτοκόλλου στο IPv6. Επίσης αντικείμενο της παρούσας εργασίας είναι η ανάπτυξη μηχανισμών και αλγορίθμων για την αποδοτική διαχείριση των πόρων, τον όσο το δυνατόν δίκαιο καταμερισμό της ποιότητας υπηρεσίας, καθώς και τη δυνατότητα συνεργασίας και διαλειτουργικότητας μεταξύ διαφορετικών αυτόνομων δικτυακών τμημάτων με αυτοματοποιημένο τρόπο (χωρίς δηλαδή να χρειάζεται η παρέμβαση ενός ανθρώπου διαχειριστή στις περισσότερες περιπτώσεις). Για το σκοπό αυτό έχουν προταθεί διάφορες προσεγγίσεις όσον αφορά μεσίτες εύρους ζώνης, οι οποίες μελετώνται στην εργασία αυτή, ενώ προτείνονται αλγόριθμοι και μηχανισμοί για τη βελτίωση της λειτουργίας και της απόδοσής τους. Το IPv4 είχε τη δυνατότητα υλοποίησης μηχανισμών QoS στο επίπεδο δικτύου με τη χρήση του πεδίου TOS (Type Of Service). Στην πράξη όμως το πεδίο αυτό έμεινε σε μεγάλο βαθμό ανεκμετάλλευτο. Το IPv6 επεκτείνει και βελτιώνει την ιδέα αυτή, παρέχοντας δύο νέα πεδία στην στάνταρ επικεφαλίδα, τα Traffic Class και Flow Label, τα οποία μπορούν να χρησιμοποιηθούν προς αυτήν την κατεύθυνση. Η χρήση των πεδίων αυτών, όπως και γενικότερα η χρήση του IPv6 βρίσκονται ακόμα σε πειραματικό επίπεδο. Καθώς όμως το IPv6 περνάει σιγά-σιγά στο προσκήνιο και ετοιμάζεται να υποκαταστήσει το κυρίαρχο έως τώρα IPv4, παρουσιάζει ιδιαίτερο ενδιαφέρον η διερεύνηση του τρόπου με τον οποίο θα αξιοποιηθούν πρακτικά οι QoS δυνατότητες που προσφέρει το IPv6. Μία σημαντική παράμετρος της υποστήριξης QoS Μηχανισμών από άκρο σε άκρο είναι η συνεργασία μεταξύ διαφορετικών αυτόνομων τμημάτων (domains) που απαιτείται προκειμένου η κίνηση να υφίσταται προνομιακή μεταχείριση καθ’ όλη τη διαδρομή της και να της παρέχονται οι αναγκαίες εγγυήσεις ποιότητας. Η διαπραγμάτευση της συνεργασίας αυτής είναι σαφές ότι πρέπει να είναι όσο το δυνατόν αυτοματοποιημένη για να μπορούν τέτοιου είδους υπηρεσίες να γνωρίσουν ευρύτερη διάδοση. Για το σκοπό αυτό έχει από το RFC 2638 της IETF οριστεί η μονάδα του Bandwidth Broker (μεσίτης εύρους ζώνης). Ελέγχει το δικτυακό φόρτο αποδεχόμενη ή απορρίπτοντας αιτήματα για συγκεκριμένο bandwidth με εγγυήσεις QoS. Οι Bandwidth Brokers χρειάζεται να εγκαθιδρύσουν σχέσεις περιορισμένης εμπιστοσύνης με τις αντίστοιχες μονάδες στα γειτονικά domains, αντίθετα με άλλες αρχιτεκτονικές που απαιτούν τον καθορισμό των χαρακτηριστικών μιας ροής στους δρομολογητές κατά μήκος του από άκρο σε άκρο μονοπατιού. Επομένως η αρχιτεκτονική του Bandwidth Broker δίνει τη δυνατότητα να κρατηθεί η πληροφορία στο επίπεδο του διαχειριστικού domain, αντί να πρέπει να κρατηθεί σε κάθε δρομολογητή, και η DiffServ αρχιτεκτονική δίνει τη δυνατότητα να περιοριστεί η πληροφορία αυτή μόνο για τους ακραίους δρομολογητές κάθε domain. Στα πλαίσια της εργασίας αυτής ασχοληθήκαμε επίσης με τη μονάδα ελέγχου αποδοχής ενός Bandwidth Broker. Προτείνεται και αξιολογείται ένας προσαρμοστικός αλγόριθμος για αιτήματα κράτησης πόρων που καταφτάνουν νωρίτερα από τον καθορισμένο χρόνο έναρξης της κράτησης. Το γεγονός αυτό επιτρέπει στον αλγόριθμο να συγκεντρώνει ένα σύνολο από πολλαπλά αιτήματα και να κάνει καλύτερη αξιοποίηση του δικτύου, χρησιμοποιώντας την υπάρχουσα βιβλιογραφία για προβλήματα χρονοδρομολόγησης. Η σημασία της παρακολούθησης και της προσαρμογής της υπολογιστικής επιβάρυνσης για τον Bandwidth Broker φαίνεται σαφέστερα όταν υπάρχει μεγάλος ρυθμός άφιξης αιτημάτων, ενώ το ζητούμενο bandwidth για κάθε κράτηση είναι μικρό, όπως στην περίπτωση πολλαπλών VoIP αιτημάτων σε μία σύνδεση υψηλού bandwidth. / The main goal of this dissertation is the study of two of the main developments related to the Internet network layer: the provisioning of Quality of Service guarantees to part of the total traffic traversing ΙΡ networks, as well as the need for upgrading the IPv4 protocol to IPv6. Also goal of this dissertation is the development of mechanisms and algorithms for the effective administration of resources, the best possible fairness in distributing the quality of service, and the possibility of cooperation and interoperability between different domains in an automated way (without the need for human intervention in most cases). For this reason, a number of approaches have been proposed related to Bandwidth Brokers. These approaches are studied in this dissertation, while new algorithms and mechanisms are proposed for the improvement of their operation and performance. IPv4 was capable of supporting QoS mechanisms at the network layer using the TOS field (Type Of Service). IPv6 advances and improves on this idea, by supplying two new fields in the standard header, called Traffic Class and Flow Label, which can be used for this purpose. The usage of these fields, as well as the usage of IPv6 is still at an early stage. However, while IPv6 comes to the foreground and becomes mature enough to replace the dominant IPv4, it is especially interesting to investigate the way that IPv6 QoS capabilities are practically going to be exploited. An important parameter for supporting end-to-end QoS mechanisms is the interaction between multiple domains so that the designated traffic is subjected to preferential treatment along the whole path. The negotiation of this interaction clearly has to be as much automated as possible, if such services are to be widely supported. For this reason, RFC 2638 from IETF has defined the Bandwidth Broker entity. According to the RFC definition, it controls the network load by accepting or rejecting requests for specific bandwidth with QoS guarantees. Bandwidth Brokers only need to establish relationships of limited trust with their peers in adjacent domains, unlike schemes that require the setting of flow specifications in routers throughout an end-to-end path. In practical technical terms, the Bandwidth Broker architecture makes it possible to keep state on an administrative domain basis, rather than at every router and the service definitions of Premium and Assured service make it possible to confine per flow state to just the leaf routers. In the framework of this dissertation we have also studied the admission control module of a Bandwidth Broker. An adaptive algorithm for advance resource reservation requests is proposed and evaluated. The algorithm gathers and evaluates multiple requests in order to better utilize the network, using previous work on timescheduling problems. The importance of monitoring and adapting the computational overhead for the Bandwidth Broker is clearly demonstrated for high request arrival rates and small bandwidth requests, such as the case for multiple VoIP requests that use a high bandwidth link.
4

O processo de migração de sistemas corporativos de comunicação TDM para plataformas convergentes IP com preservação de ativos

Gianoto, Antonio Carlos 29 June 2006 (has links)
Made available in DSpace on 2016-04-18T21:39:45Z (GMT). No. of bitstreams: 4 Antonio Carlos GIANOTO1.pdf: 620239 bytes, checksum: aa779772dff23531ab717870d36823d3 (MD5) Antonio Carlos GIANOTO2.pdf: 1522259 bytes, checksum: 928d1a566cc9977b69a13b358fe13a50 (MD5) Antonio Carlos GIANOTO3.pdf: 2036577 bytes, checksum: 4ef7b886a0d20792d494deb085435041 (MD5) Antonio Carlos GIANOTO4.pdf: 1519186 bytes, checksum: cce13633bbc1cf7d5714a8dd727dd008 (MD5) Previous issue date: 2006-06-29 / Fundo Mackenzie de Pesquisa / The aim of this elaboration is to present a study of the migration process involved transforming the digital PBX (Private Branch Exchange), TDM (Time Division Multiplex), SPC (Stored Program Control) based platforms of corporate communications on technology to converged IP (Internet Protocol) systems supported by the TCP/IP (Transmission Control Protocol/Internet Protocol) protocol. This proposal analyzes the necessary interventions in order to preserve the investments made in these platforms, integrating them to existent data networks. Beside other benefits presented in this work, one key advantage is the possibility to transport voice over an existing data infrastructure, optimizing usage of carrier connections. / O objetivo desta dissertação é o de apresentar um estudo do processo de migração de plataformas de voz PABX (Private Automatic Branch Exchange) TDM (Time Division Multiplex) de comunicações corporativas baseadas na tecnologia CPA-T (Controle por Programa Armazenado estágio de comutação temporal digital), para sistemas convergentes suportados pelo protocolo TCP/IP (Transmission Control Protocol/Internet Protocol). São analisadas as intervenções necessárias para esta migração, preservando ao máximo os investimentos efetuados nestas plataformas, integrando-as as redes de dados existentes. Dentre outras vantagens apresentadas no texto, destaca-se a otimização dos acessos fornecidos pelas operadoras de telecomunicações pelo compartilhamento da infra-estrutura da rede de dados para o tráfego de sinais de voz.
5

Arquitetura de mobilidade IPv6 entre cidades digitais = Mobile IPv6 architecture between digital cities / Mobile IPv6 architecture between digital cities

Nunes, Fábio Pessoa 21 August 2018 (has links)
Orientador: Leonardo de Souza Mendes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-21T21:10:42Z (GMT). No. of bitstreams: 1 Nunes_FabioPessoa_M.pdf: 6956532 bytes, checksum: 55194ac0a721f75279923f8424903edc (MD5) Previous issue date: 2012 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica
6

Implementace kvality služby do řízení síťového prvku / Implementation of quality of service in the control of a network element

Boháč, Martin January 2008 (has links)
The main task of the Master Thesis is introduction into problems of quality of service in converged networks especially with use of IP protocol version 6. Converged networks are able to transfer different data types - voice, data or multimedia stream. Design of active network unit is realized in Matlab Simulink. Designed model consists of simple network with some computer terminals which are connected with network element - switch. Switch model simulates real traffic of computer terminals, that are sending data to remote users. Packets in switch are sorting by data stream type and QoS. Switch is managed by neuron network. Neuron network reacts to input data and controls switch depending on type of recipient. Switch model can be used in laboratory exercising. Solving this theme needs basic skill in Simulink and theme can be done in one laboratory exercise.
7

Komunikační protokoly pro optické bezkabelové spoje / Communication protocols for Free-Space Optical links

Šedo, Ondrej January 2015 (has links)
This master’s thesis is focused on behaviour of the TCP/IP protocol on free-space optical link which is affected by the effect of atmospheric turbulence. This causes fluctuation of the received optical power and therefor bit error rate changes. In the simulation model short-time bit error rate is calculated from random generated received optical signal and then used in time-domain analysis of the OMNeT++ network simulator. A buffer in transmitter is designed based on simulation results. It pauses the data transmitting in cases of FSO link outage. This method is then implemented into FPGA device.
8

Návrh aplikace pro správu tenkých klientů / Thin Client Management Solution Design

Juhaňák, Filip January 2013 (has links)
This thesis focuses on designing and developing a centralized management and configuration solution for the thin clients offered by the OldanyGroup s.r.o. company. The purpose of this application is to simplify the thin client administration and control for customers as well as to improve the competitiveness of the whole thin client solution offered by the company.
9

Komunikační protokoly pro optické bezkabelové spoje / Communication protocols for Free-Space Optical links

Šedo, Ondrej January 2016 (has links)
This master’s thesis is focused on behaviour of the TCP/IP protocol on free-space optical link which is affected by the effect of atmospheric turbulence. This causes fluctuation of the received optical power and therefor bit error rate changes. In the simulation model short-time bit error rate is calculated from random generated received optical signal and then used in time-domain analysis of the OMNeT++ network simulator. A buffer in transmitter is designed based on simulation results. It pauses the data transmitting in cases of FSO link outage. This method is then implemented into FPGA device.
10

Sistema supervisório de parâmetros de máquinas elétricas via TCP/IP e painel eletrônico de mensagens / Supervisory system of electric machine\'s parameter via TCP/IP and message displays

Ranieri, Fernando 17 August 2007 (has links)
Com o advento da internet, a comunicação entre sistemas remotos foi amplamente facilitada, tornando viável a aplicação de sistemas supervisórios através dela, principalmente via protocolo TCP/IP. Embora esses sistemas já sejam empregados na indústria, principalmente utilizando como driver os controladores lógicos programáveis (CLP\'s), a implementação de qualquer sistema mais simples de supervisionamento teria um custo elevado, devido tanto ao preço do hardware quanto do software envolvido. Além disso, os programas supervisórios existentes fornecem um número limitado de recursos de visualização, que se restringem principalmente ao software. Assim, o que se propõe nesse trabalho é um sistema supervisório de baixo custo, via TCP/IP, aplicado em máquinas elétricas, mas que pode ser generalizado na supervisão de outros tipos de sistemas, onde o monitoramento remoto é necessário. Além da exibição convencional dos parâmetros supervisionados através de gráficos e labels, o sistema permite também que esses sejam exibidos através de painéis eletrônicos, fornecendo assim, uma nova interface visual ao usuário com o intuito de facilitar sua supervisão. / The advent of internet simplified the comunication between remote systems, allowing the application of supervisory systems through the internet, mainly using the TCP/IP protocol. Although these systems have already been employed in industry, using the Programmer Logic Controller (PLC\'s) as driver, the implementation of any simple supervisory system could have an expensive cost, due to the prices of hardware and software employed. Moreover, the existing supervisory systems provide limited visual resources, restricted to the used software. So, this work presents a low cost supervisory system, via TCP/IP, applied to electric machines but it can be generalized in the supervision of differents types of systems, where the remote monitoring is necessary. Besides the conventional displaying of the monitored parameters through graphics and labels, the developed system allows the exhibition of the supervisioned parameters using eletronic panels, providing an alternative visual interface to the user so that their supervision becomes easier.

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