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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.
341

Analyze and compare methods of bridging Layer 2 Tunneling Industrial Ethernet over IP-based networks

Stenberg, Eric, Abdennour, Rim January 2024 (has links)
This report aims to compare different layer 2 tunneling protocols in order to determine what advantages and disadvantages each protocol comes with. Since wireless communication is becoming more used demand for these protocols has risen. The main goal is to help industries, like Hardware Meets Software (HMS), choose the most suitable layer 2 tunneling protocol and give a detailed view of each protocol. To compare the protocols, information about various protocols was gathered as well as other studies done on layer 2 tunneling protocols. A decision was then made on the protocols to focus on, Layer 2 Tunneling Protocol (L2TP), Internet Protocol Security (IPsec), Virtual eXtensible Local-Area Network protocol (VXLAN), Generic Routing Encapsulation protocol (GRE), and Network Virtualization using Generic Routing Encapsulation protocol (NVGRE). Furthermore, tests were done on non-tunneling, L2TP together with IPsec and VXLAN, using two laptops, two gateways as well as a shark trap together with Wireshark to record the traffic. These tests were recorded and documented. The results of the tests were used to calculate the protocol’s latency, throughput and jitter. The background research together with the tests concluded in specific protocol characteristics, with different use cases for each protocol. The tests show that non-tunneling was the fastest communication. The L2TP together with the IPsec had better latency and jitter while VXLAN had better throughput. Using other studies together with our tests, different advantages and disadvantages with each protocol was discussed and it was concluded that deeper research would be needed toconclude which protocol best suits HMS, but that L2TP with IPsec outperformed VXLAN on 2 of the 3 main factors. Finally, the methodology is discussed with the factors of reliability, accuracy, and limitation.
342

Short-term Ethernet traffic prediction using a Kalman filter

Vanderbilt, Marisin C. 01 October 2000 (has links)
No description available.
343

Entwicklung des Kommunikationsteilsystems für ein objektorientiertes, verteiltes Betriebssystem

Becher, Mike 09 November 1998 (has links)
Thema dieser Arbeit ist die Entwicklung eines Kommunikationsteilsystems fuer das Experimentiersystem CHEOPS zur Ermoeglichung einer Interobjektkommunika- tion zwischen Objekten auf dem gleichen bzw. verschiedenen Systemen. Ausgangspunkte stellen dabei eine verfuegbare Implementation eines Ethernet- Treibers der Kartenfamilie WD80x3 fuer MS-DOS, eine geforderte Kommunikations- moeglichkeit mit UNIX-Prozessen sowie die dort benutzbaren Protokoll-Familien dar. Die Arbeit beschaeftigt sich mit der Analyse und Konzipierung des Ethernet- Treibers sowie der Internet-Protokoll-Familie fuer CHEOPS als auch deren Implementation resultierend in einem minimalen Grundsystem. Weiterhin wird ein erster Entwurf fuer ein spaeter weiterzuentwickelndes bzw. zu vervoll- staendigendes Netz-Interface vorgeschlagen und durch eine Beispiel-Implemen- tierung belegt.
344

Wireless communications infrastructure for collaboration in common space

Metingu, Kivanc 03 1900 (has links)
Approved for public release, distribution is unlimited / Modern technology is making virtual environments a part of daily life. However, some constraints about the usage of virtual environments, such as the need for high performance and well-configured computers, prevent users from accessing virtual environments in some places other than special computer rooms. Mobile devices may be used to solve this limitation in a virtual environment. The remote-control approach to access virtual worlds on the Internet or on a corporate network is a new concept that opens new doors to users. First step of this approach is already in use, such as games implemented for mobile devices using the screen of a mobile device as display, and has given satisfying results for some users. This research will take the user, who not only wants to be mobile but also does not want to sacrifice high resolution textures and complex models, closer to his/her goal. Mobile devices provide mobility to the user, but sacrifice not only the reality of the virtual environments but also screen size, which is very important for visibility of complex virtual environments. The hybrid approach with wireless internet connection by using mobile devices as remote control gives the user the advantages of mobility over desktop PCs. On the other hand, the realism provided by high-quality PCs on the server side exceeds the capabilities of mobile devices. / Lieutenant Junior Grade, Turkish Navy
345

Siemens och Rockwell Automation : En jämförande studie mellan styrsystem

Rexhaj, Kastriot January 2017 (has links)
Detta arbete har syftat till att ställa två av de större automationstillverkarna Siemens och Rockwell Automation mot varandra kring utvalda faktorer som: prestanda, kommunikation och tillgängliga mjukvaruverktyg. Studien har utformat tester på olika PLC-enheter från respektive tillverkare, redogjort för skillnader i de erbjudna kommunikationslösningarna samt analyserat mjukvaruverktygen utifrån utvalda egenskaper men också internationellt erkända standarder. Undersökningen har visat på bättre prestanda på processorer från Rockwell Automation än motsvarande från Siemens för ett givet tillämpningsområde. Vad befattar kommunikationslösningar med ethernet-teknologi har Siemens visat på bättre prestanda, stabilare kommunikation och ett mer komplett ekosystem som svarar på flera av de behov som kan uppstå i industriverksamhet. Mjukvaruverktygen från Siemens erbjuder mer objekt-orienterad funktionalitet och har visat sig betydligt mer kompatibel med den väletablerade standarden IEC 61131-3 som utformar programmeringsmetodiker för PLC-enheter och är tänkt att svara mot framtidens behov av interoperabilitet och effektivisering. Av resultaten som fåtts har en bedömning gjorts att Siemens erbjuder ett mer fördelaktigt utbud av produkter och tjänster som svarar väl mot framtidens krav. / This paper treats two competing suppliers of automation technology, Siemens and Rockwell Automation and directly compares them for a given set of factors in the following categories: performance, communication and software tools. The study consists of performance tests made on different PLC’s from these suppliers, considerations in the differences of communication technology and analysis of the programming tools according to chosen criteria’s but also by the degree of compliance with internationally established standards. The tests have shown the PLC from Rockwell Automation as having better performance for the chosen criteria (PLC’s for small to medium sized machines). Siemens offers more performance and more stable industrial ethernet communication over ProfiNET than does Rockwell Automation with EtherNet/IP. Accordingly, Siemens offers more flexibility in meeting future industrial needs. The software tools provided by Siemens offer a more object-oriented approach for programming PLC’s than equivalent tools from Rockwell Automation. TIA Portal offered by Siemens is more than twice as compliant with the internationally accepted standard IEC 61131-3 as Studio 5000 from Rockwell and in being more compliant benefits from increased interoperability and effective programming. The results show that Siemens’ products and services for automation benefits the customer in long term viability.
346

Método para detecção de anomalias em tráfego de redes Real Time Ethernet aplicado em PROFINET e em SERCOS III / Method for detecting traffic anomalies of Real Time Ethernet networks applied to PROFINET and SERCOS III

Sestito, Guilherme Serpa 24 October 2018 (has links)
Esta tese propõe uma metodologia de detecção de anomalias por meio da otimização da extração, seleção e classificação de características relacionadas ao tráfego de redes Real Time Ethernet (RTE). Em resumo, dois classificadores são treinados usando características que são extraídas do tráfego por meio da técnica de janela deslizante e posteriormente selecionadas de acordo com sua correlação com o evento a ser classificado. O número de características relevantes pode variar de acordo com os indicadores de desempenho de cada classificador. Reduzindo a dimensionalidade do evento a ser classificado com o menor número de características possíveis que o represente, são garantidos a redução do esforço computacional, ganho de tempo, dentre outros benefícios. Posteriormente, os classificadores são comparados em função dos indicadores de desempenho: acurácia, taxa de falsos positivos, taxa de falsos negativos, tempo de processamento e erro relativo. A metodologia proposta foi utilizada para identificar quatro diferentes eventos (três anomalias e o estado normal de operação) em redes PROFINET reais e com configurações distintas entre si; também foi aplicada em três eventos (duas anomalias e o estado normal de operação) em redes SERCOS III. O desempenho de cada classificador é analisado em suas particularidades e comparados com pesquisas correlatas. Por fim, é explorada a possibilidade de aplicação da metodologia proposta para outros protocolos baseados em RTE. / This thesis proposes an anomaly detection methodology by optimizing extraction, selection and classification of characteristics related to Real Time Ethernet (RTE) network traffic. In summary, two classifiers are trained using features which are extracted from network traffic through the sliding window technique and selected according to their correlation with the event being classified. The number of relevant characteristics could vary according to performance indicators of each classifier. Reducing the dimensionality of the event to be classified using the smallest number of characteristics which represent it, guarantees reduction in computational effort, processing time, among other benefits. The classifiers are compared according to performance indicators: accuracy, false positive rate, false negative rate, processing time and relative error. The proposed methodology was used to identify four different events (three anomalies and normal operation) in real PROFINET networks, using different configurations. It was also applied in 3 events (two anomalies and normal operation) in SERCOS III networks. The results obtained are analyzed in its particularities and compared with related research. Finally, the possibility of applying the proposed methodology for other protocols based on RTE is explored.
347

Lastfördelning och effektmätning med Arduino och PLC

Klintrot, Oskar, Forsström, Daniel January 2014 (has links)
Detta arbete var beställt av Sjöfartshögskolan i Kalmar. Skolan ville ha en enhet som kunde mäta aktiv-, reaktiv- och skenbar effekt, ström, spänning, frekvens och cosϕ på en generator och som kommunicerade vidare dessa värden till en PLC. Detta för att kunna lastfördela lasten mellan ett antal generatorer i kursen Tillämpad elteknik 15 hp där studenterna bygger en generatorinstallation med tre generatorer. Ett funktionsblock för lastfördelning skulle också programmeras. Prototypen som konstruerades baserades på en Arduino Ethernet och kommunikationen löstes med Modbus TCP/IP över Ethernet. Ett lastfördelningsprogram programmerades i form av ett funktionsblock som studenterna kunde importera till CoDeSys v2.3 och använda i sina installationer. Prototypen kunde läsa av värdena med ungefär samma noggrannhet som ett kommersiellt instrument som använder sig av samma mätteknik som prototypen. Uppdateringsfrekvensen var dock lägre än hos ett kommersiellt instrument. Kommunikationen med PLC:n fungerade utan problem. Då ingen undervisning hölls i arbetets slutskede kunde inte lastfördelningen testas på en fullskalig anläggning. Lastfördelningsprogrammet klarade dock av att hålla rätt frekvens på en ensam generator och fungerade som tänkt när programmet testades i en simulator. Prototypen gav fel mätvärden vid kapacitiv last. Vid jämförelse med en kommersiell tångamperemeter visade sig mätfelet bero på mätmetoden då båda gav liknande resultat. Som referens användes en professionell elkvalitetsanalysator. Alla uppdragsgivarens krav blev uppfyllda och arbetet kommer att kunna användas i undervisningen. / This thesis was ordered by Kalmar Maritime Academy. The request was for a device that could measure active, reactive and apparent power, as well as frequency, voltage, current and cosϕ on a generator. The measured values would be communicated to a PLC for use in a load sharing program between a number of generators in the course Tillämpad elteknik, 15 ECTS. In that course the students constructs a three-generator electric power grid. Included in the request was also to program a load sharing program. The prototype being constructed was based on the Arduino Ethernet, and the communication was enabled by means of the Modbus TCP/IP protocol over Ethernet. A load sharing program was created in the form of a function block which the student could import into the CoDeSys for use in the generator systems. The prototype could measure values with close to the same accuracy as a commercial available instrument that were using the same technique for measuring. The refresh rate was however lower than the commercial available instrument. Communication with the PLC worked without any issues. No full-scale testing could be done since no course was held during the final stages of the thesis, however the load sharing program could keep frequency on a single generator alone and worked in a simulated soft environment. Measuring errors occurred when measuring a capacitive load. When comparing to a commercial available clamp meter, the same errors occurred. As a reference a professional power and energy quality analyser was used. All the requests were fulfilled and the result of this thesis will be used in the educational programme at the Academy.
348

Ανάλυση και αποτίμηση της απόδοσης παθητικών οπτικών δικτύων Ethernet για πολυδιάστατη κίνηση

Κόκιου, Αντωνία 07 June 2013 (has links)
Η επιθυμία του ανθρώπου για ποιοτική και αδιάκοπη επικοινωνία, έχει ωθήσει την τεχνολογία να κάνει άλματα εξέλιξης. Η συνεχής ανάπτυξη των απαιτήσεων των χρηστών των τηλεπικοινωνιακών δικτύων, καθιστά αναγκαία την ανανέωση των τεχνολογιών και ιδιαίτερα την αύξηση του παρεχόμενου εύρους ζώνης, ώστε να συμβαδίζει με τις ανάγκες τους. Γι’αυτό το λόγο τα τελευταία χρόνια έχουν εμφανιστεί οι οπτικές ίνες, που με τα πλεονεκτήματα που παρουσιάζουν, κερδίζουν ολοένα και περισσότερο τις αγορές και τους καταναλωτές. Στην παρούσα διπλωματική παρουσιάζονται τα πλεονεκτήματα και οι τεχνολογίες που χρησιμοποιεί ένα δίκτυο βασισμένο σε οπτικές ίνες (παθητικό οπτικό δίκτυο – PON). Εξετάζεται τόσο η τεχνολογία TDMA, όσο και η WDMA στα PONs. Η μελέτη γίνεται πάνω στο πρότυπο ΕΡΟΝ (Ethernet-PON), που ορίστηκε ως το καταλληλότερο συγκριτικά με άλλα παρόμοιά του. Πιο συγκεκριμένα, εξετάζεται η διάθεση εύρους ζώνης στο ανοδικό κανάλι (από τον χρήστη προς το τηλεπικοινωνιακό κέντρο) στα συστήματα ΕΡΟΝ και τι αποτελέσματα και συμπεράσματα μπορούν να ληφθούν. Αρχικά, αναφέρεται μια προηγούμενη μελέτη ενός ΕΡΟΝ η οποία κάνει χρήση του αλγορίθμου IPACT, της περιορισμένης υπηρεσίας (limited service) του αλγορίθμου και υποστηρίζει μονοδιάστατη ανοδική κίνηση δεδομένων. Το δίκτυο ΕΡΟΝ μοντελοποιείται και προσφέρει αποτελέσματα ύστερα από μαθηματική ανάλυση με χρήση της γλώσσας προγραμματισμού C, καθώς και αποτελέσματα με τη χρήση της γλώσσας προσομοίωσης SIMSCRIPT II.5. Στη συνέχεια, περιγράφεται και μοντελοποιείται ένα δίκτυο ΕΡΟΝ που κάνει χρήση της σταθερής υπηρεσίας (fixed service) του αλγορίθμου IPACT και υποστηρίζει πολλαπλές κατηγορίες υπηρεσιών ανοδικής κίνησης δεδομένων με διαφορετικές προτεραιότητες. Και σε αυτή την περίπτωση, το δίκτυο ΕΡΟΝ προσφέρει αποτελέσματα τόσο από ένα αναλυτικό μοντέλο, όσο και από ένα μοντέλο προσομοίωσης. Τέλος, περιγράφεται και μοντελοποιείται ένα δίκτυο όμοιο με το προηγούμενο δίκτυο ΕΡΟΝ, με τη διαφορά να έγκειται στη χρήση της τεχνολογίας WDM στο ΕΡΟΝ. Η μελέτη σε αυτό το τμήμα της εργασίας γίνεται με χρήση επίσης της σταθερής υπηρεσίας (fixed service) του αλγορίθμου IPACT και υποστηρίζει πολλαπλές κατηγορίες υπηρεσιών ανοδικής κίνησης δεδομένων με διαφορετικές προτεραιότητες. Με αυτόν τον τρόπο επιτυγχάνεται μια σημαντική αύξηση του διαθέσιμου εύρους ζώνης του ανοδικού καναλιού που προσφέρεται στους χρήστες. Για άλλη μια φορά παρουσιάζονται αποτελέσματα ύστερα από ανάλυση και προσομοίωση του μοντέλου, με χρήση, όπως και προηγουμένως, της γλώσσας προγραμματισμού C και της γλώσσας προσομοίωσης SIMSCRIPT II.5. Τα συμπεράσματα που εξάγονται, ύστερα από τις παραπάνω μελέτες, είναι άξια προσοχής. / In the past few years technology, in the communication field, has made great progress due to the fact that people desire more and more good quality of service. The continuous demand for development of the subscribers using the telecommunication services, necessitates the technological renewal and especially the increase of the available bandwidth. For this reason, optical fibers have appeared in the networking field and they are becoming more known by the users and in the market every day. In this dissertation the advantages and the technologies a network, based on optical fiber uses, are presented. An optical fiber network it is also called Passive Optical Network (PON). The TDMA (Time Division Multiplexing Access) and WDMA (Wavelength Division Multiplexing Access) technologies are examined. The study is based on an EPON (Ethernet-PON) standard, which was chosen as the most suitable among others. More specifically, the available upstream (from the users to the Central Office) bandwidth in an EPON model and the results that can be deduced are examined. In the beginning, a previous study of an EPON which uses the IPACT (Interleaved Polling with Cycle Time) algorithm is reported. The EPON network uses the limited service of the IPACT algorithm and supports a single rate. A specific model of an EPON network is studied and results using the C programming language and the simulation language SIMSCRIPT II.5 are given. Moreover, an EPON network which uses the fixed service of the IPACT algorithm which supports a multi-rate upstream with different priorities is described and modeled. In this case as well, the EPON model network gives results based on analysis and simulation. In the end, a same EPON network, as the one described before, is studied and modeled having as a difference that a WDM technology is used. The fixed service of the IPACT algorithm is used and a multi-rate upstream with different priorities are supported again. With this different technology, an important increase in the available upstream bandwidth which is provided to the users is accomplished. Once again, the results are presented after an analysis and a simulation of the model, using the programming language C and the simulation language SIMISCRIPT II.5. The extracted results which the models can offer are worthy of attention.
349

[en] GENERATION OF BUILT-IN OPTICAL INTELIGENCE ON ETHERNET / IP NETWORKS / [pt] GERAÇÃO DE INTELIGÊNCIA ÓPTICA EM REDES ETHERNET / IP

HENRIQUE JOSE PINTO PORTELA DA SILVA 06 July 2005 (has links)
[pt] O principal objetivo desta dissertação consiste na geração de novas funcionalidades inteligentes em redes ópticas associadas aos protocolos IP e Gigabit Ethernet, através da utilização de circuitos integrados programáveis operando na taxa do Gigabit. A padronização Ethernet é apresentada através das camadas PHY e MAC, destacando suas funções, interfaces e os tipos de chips disponíveis no mercado. A camada PHY do padrão Ethernet para meios ópticos é detalhada. Algumas tecnologias de chips são discutidas, entre elas o crescimento dedicado, os ASICs, as NPUs e as tecnologias programáveis: FPGAs e CPLDs. O conceito de inteligência óptica e o perfil de camadas equivalentes associados a este conceito são introduzidos. Um novo elemento de rede dedicado à inserção de sinalização na camada óptica é apresentado, destacando-se sua estrutura, sua realização, seu detalhamento para utilização em redes. Diversas montagens experimentais com o elemento desenvolvido são utilizadas para demonstrar as características do sistema, entre elas a eficiência da utilização da tecnologia de FPGAs e a transparência da inteligência na camada óptica para o padrão Ethernet. / [en] The main objective of this work is the generation of new functionalities in optical networks, associated to the Ethernet and IP protocols, by the use of programmable integrated circuits operating in Gigabit rates. The Ethernet standard is presented through its PHY and MAC layers, highlighting its functions, interfaces and the types of commercially available ICs. The Ethernet standard PHY layer for optical media is described. Some IC technologies are discussed, such as dedicated growth, ASICs, NPUs and the programmable technologies: FPGAs e CPLDs. The concept of built-in optical intelligence and a new layers model associated to it are presented. A new network element, dedicated to the insertion of signaling in the optical layer is also presented, and special attention is dedicated to its structure, to its implementation and to the aspects of its use in networks. Several experimental setups using the developed element are shown, demonstrating the characteristics of the system, particularly the efficiency obtained by the use of FPGA technology and the transparency of the optical intelligence with respect to the Ethernet standard.
350

Highly variable real-time networks: an Ethernet/IP solution and application to railway trains

Constantopoulos, Vassilios 03 July 2006 (has links)
In this thesis we study the key requirements and solutions for the feasibility and application of Ethernet-TCP/IP technology to the networks we termed Highly-Variable Real-Time Networks (HVRN). This particular class of networks poses exceptionally demanding requirements because their physical and logical topologies are both temporally and spatially variable. We devised and introduced specific mechanisms for applying Ethernet-TCP/IP to HVRNs with particular emphasis on effective and reliable modular connectivity. Using a railroad train as a reference, this work analyzes the unique requirements of HVRNs and focuses on the backbone architecture for such a system under Ethernet and TCP/IP. / Doctorat en sciences appliquées / info:eu-repo/semantics/nonPublished

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