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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

none

Huang, Wen-Chun 07 August 2000 (has links)
Abstract Due to the fast improvement of information technology ,the application of internet is spreading in our society ,so is electronic commerce(EC).In hence ,many companies are starting to provide all kinds of services on the internet .In the stock market , stock brokers provide online stock trading service ,that enable the stock trading will not limited by time¡Bregions and people any more .However ,the internet has became a new way of investment. In Taiwan, there are more than 70 online stock brokers and one million investors that use online stock trading, and the volume of online stock trading is 5.87% to the total stock market. According to relative documents and some professional assessment mechanism, this study generalize 15 indexes of satisfaction of online stock trading questionnaires to query online stock brokers and investors, answers that we want to know are: what are the features of online trading investors? What are their responses of online stock trading? What are the factors that influence the indexes of satisfaction of online stock trading? What are the differences of satisfaction between online stock brokers and investors? The research outcome shows that investors which use online stock trading service is more younger and educated¡Bfrequency of trade is fewer¡Bthe amount of money is not much and the investors prefer self-service .And security of transaction is the primary factors that make the investors does not like online stock trading. Furthermore ,this study has generalized five primary factors that influence the satisfaction of online stock brokers and investors ,they are :¡uweb design¡v¡B¡unet speed ¡v¡B¡ufinancial specialty¡v¡B¡ucustomer services¡vand¡ufees¡v. And still other ,in the comparison of satisfaction between online stock brokers and investors , there is a gap in the aspect of ¡ufinancial specialty¡v,and by the further analysis ,there are gaps in the following index:¡urichness and quality of research reports¡v¡B¡usupply of other financial instruments¡v¡B¡uquery of customers information¡vand ¡usecurity of transaction¡v
12

Kapitalmarktorientierte Bewertung strategischer Optionen beim Einstieg in neue Märkte am Beispiel des UK Internet Brokerage /

Reich-Rohrwig, Florian. January 2001 (has links) (PDF)
Diss. Wirtsch.-wiss. St. Gallen, 2000 ; Nr. 2468. / Literaturverz.
13

Komparace postavení společnosti Fio banka, a.s. v konkurenci on-line zprostředkovatelů burzovních obchodů v České Republice

Csakvaryová, Lenka January 2014 (has links)
The theme of the work is " Comparison of Fio Banka. a.s. position in the competition of online brokers in Czech Republic." The work's objective is to assess the position of Fio banka with regard to competition of online brokers on the market in the Czech Republic, to recognize possible shortcomings of Fio Banka a.s. in comparison to the competitions and to suggest their removal. To assess the status of Fio Banka a.s. method of Benchmarking was chosen, which allows comparison of competition according to parameters associated with the client services. Such parameters were chosen that can be used to competitive advantage over other online brokers.
14

Android Phone Controlled Beagle Board Based PSCR in a Dynamic Spectrum Access Environment

Radhakrishnan, Aravind 05 October 2010 (has links)
Public Safety Cognitive Radio (PSCR) is a Software Defined Radio(SDR) developed by the Center for Wireless Telecommunications (CWT) at Virginia Tech. PSCR can configure itself to interoperate with any public safety waveform it finds during the scan procedure. It also offers users the capability to scan/classify both analog and digital waveforms. The current PSCR architecture can only run on a general purpose processor and hence is not deployable to the public safety personnel. In the first part of this thesis an Android based control application for the PSCR on a Beagle Board(BB) and the GUI for the control application are developed. The Beagle Board is a low-cost, fanless single board computer that unleashes laptop-like performance and expandability. The Android based Nexus One connected to the Beagle Board via USB is used to control the Beagle Board and enable operations like scan, classify, talk, gateway etc. In addition to the features that exist in the current PSCR a new feature that enables interoperation with P25 (CPFSK modulation) protocol based radios is added. In this effort of porting the PSCR to Beagle Board my contributions are the following (i) communication protocol between the Beagle Board and the Nexus One (ii) PSCR control application on the Android based Nexus One (iii) detection/classification of P25 protocol based radios. In the second part of this thesis, a prototype testbed of a Dynamic Spectrum Access (DSA) broker that uses the Beagle Board PSCR based sensor/classifier is developed. DSA in simple terms is a concept that lets the user without license (secondary user) to a particular frequency access that frequency, when the licensed user (primary user) is not using it. In the proposed testbed we have two Beagle Board based sensor/classifiers that cooperatively scan the spectrum and report the results to the central DSA broker. The DSA broker then identifies the frequency spectrum without primary users and informs the secondary users about the free spectrum. The secondary users can then communicate among each other using the frequency band allocated by the DSA broker. When the primary user enters the spectrum occupied by the secondary user, the DSA broker instructs the secondary user to use a different spectrum. Based on the experiments conducted on the testbed setup in the CWT lab environment, the average time taken by the DSA broker to detect the presence of primary user is 0.636 secs and the average time taken for the secondary user to leave the frequency band that interferes with the primary user is 0.653 secs. / Master of Science
15

The Research of Insurance Brokers¡¦ Industry entering Mainland China - Case of Tai-Yung Insurance Broker

Tseng, Nien-Cheng 22 August 2011 (has links)
Abstract The research uses reference materials from the insurance industry and the insurance brokerer industry, to do further study and analysis. Then we use a business case study ¡V Tai-yung Insurance Broker (Beijing) Co., to understand the past development of the company. After further study, a qualitative analysis is used through interviews with several insurance industry¡¦s experts and managers. In addition to understanding the differences between the past and the present conditions of the industry, but to explore the opportunities and impacts the insurance brokerage industry in Taiwan might encountered to entering the mainland market after running the ECFA (Economic Cooperation Framework Agreement). Finally comes up with conclusions and recommendations. Keywords¡GThe Insurance Broker Industry¡BMainland China¡BTai-yung Insurance Broker¡BExpert Interview( Delphi technique)¡BCase Study
16

Evaluating the effect of the legislative and regulatory requirements in the financial services industry / David Pieter van der Westhuizen

Van der Westhuizen, David Pieter January 2014 (has links)
South Africa has faced many changes in the last 20 years. There are some glaringly obvious ones such as democracy while others, such as the considerable increase of the legislative and regulatory requirements in the financial-services industry, are more subtle. Both however, have far-reaching consequences for both individuals and businesses. In Schaeffer's keynote address at the 2011 Financial Planning Convention, the global trends currently influencing the financial-planning profession were pointed out. These included the move towards a more relationship-based approach between financial planners and their clients, with holistic service offerings and regulatory change. Currently close to 100 000 Financial Services Board (FSB)-registered brokers/ advisors/ planners/ consultants claim to offer financial advice. Of these representatives only 4 600 (approximately) are Certified Financial Planner® professionals. The Financial Planning Institute of Southern Africa (FPI) maintains that the regulatory environment governing the financial industry is dynamic. Coupled with a tumultuous economic environment, this enforces the importance of an expert to assist individuals and businesses in planning for the future. The primary purpose of the Financial Advisory and Intermediaries Services Act (FAIS Act) is to: 1. protect the client against indecorous conduct by the financial service provider (FSP) and its representatives when providing financial advice and/or rendering intermediary services to clients; 2. ensure economic efficiency of the industry; 3. ensure that clients of FSPs are provided with sufficient information regarding their financial products, the representatives selling the products, the represented FSP and the product provider offering the products. The effect of the FAIS Act is that key individuals and representatives are now being held responsible for their actions, which may include providing incorrect information or not having sufficient qualifications or experience. According to the FSB the FAIS Fit and Proper requirements determine a set of requirements that all FSPs, key individuals and representatives need to comply with. The Determination of Fit and Proper Requirements of 2008 outlines the categories of fit and proper requirements for FSPs, their key individuals and representatives. The categories of the FAIS Fit and Proper requirements are: - honesty and integrity requirements for FSPs, key individuals and representatives; - competency requirements of FSPs, key individuals and representatives; - experience requirements of FSPs, key individuals and representatives; - qualifications requirements of key individuals and representatives; - regulatory examinations requirements of key individuals and representatives; - continuous professional development requirements of FSPs, key individuals and representatives; - operational ability of FSPs, key individuals and representatives; and - solvency of FSPs. The empirical study of the research was conducted nationally, within South Africa. The focus of the study was to investigate the perception of financial planners with regard to the regulatory and legislative prescriptions of the financial-services industry. The general objective of the study is to provide a quantitative measure of the perception of financial planners of the effect that the legislative and regulatory requirements in South Africa have on the ethicality of the financial-planning industry. To achieve this objective, the empirical study focussed on the responsibilities of financial-services providers and the FAIS fit and proper requirements as set out by the FAIS Act. The population identified for the empirical study consisted of financial planners that provide advisory and/or intermediary services in South Africa. The population of the study consisted of the full advisory complement, 826, which form part of the advisory division of a major South African financial-services provider. These financial planners are located across South Africa, in all nine provinces and in rural and metropolitan areas. Based on the result of the adjusted sample size equation, the required sample size for the study is reduced from 266 to 201. A total of 260 responses were received for the study which ensures a high level of accuracy is achieved from the findings of the research. The results of the empirical study provide ample proof that financial planners support the necessity and specificity of the FAIS fit and proper requirements as defined by the FAIS Act. Additionally, the financial planners agree that the determinants of the FAIS Act are not only beneficial to the sustainability and ethicality of the industry, but also support the success of the planner and ultimately ensure that clients receive the best possible financial advisory and/or intermediary services. / MBA, North-West University, Potchefstroom Campus, 2015
17

Evaluating the effect of the legislative and regulatory requirements in the financial services industry / David Pieter van der Westhuizen

Van der Westhuizen, David Pieter January 2014 (has links)
South Africa has faced many changes in the last 20 years. There are some glaringly obvious ones such as democracy while others, such as the considerable increase of the legislative and regulatory requirements in the financial-services industry, are more subtle. Both however, have far-reaching consequences for both individuals and businesses. In Schaeffer's keynote address at the 2011 Financial Planning Convention, the global trends currently influencing the financial-planning profession were pointed out. These included the move towards a more relationship-based approach between financial planners and their clients, with holistic service offerings and regulatory change. Currently close to 100 000 Financial Services Board (FSB)-registered brokers/ advisors/ planners/ consultants claim to offer financial advice. Of these representatives only 4 600 (approximately) are Certified Financial Planner® professionals. The Financial Planning Institute of Southern Africa (FPI) maintains that the regulatory environment governing the financial industry is dynamic. Coupled with a tumultuous economic environment, this enforces the importance of an expert to assist individuals and businesses in planning for the future. The primary purpose of the Financial Advisory and Intermediaries Services Act (FAIS Act) is to: 1. protect the client against indecorous conduct by the financial service provider (FSP) and its representatives when providing financial advice and/or rendering intermediary services to clients; 2. ensure economic efficiency of the industry; 3. ensure that clients of FSPs are provided with sufficient information regarding their financial products, the representatives selling the products, the represented FSP and the product provider offering the products. The effect of the FAIS Act is that key individuals and representatives are now being held responsible for their actions, which may include providing incorrect information or not having sufficient qualifications or experience. According to the FSB the FAIS Fit and Proper requirements determine a set of requirements that all FSPs, key individuals and representatives need to comply with. The Determination of Fit and Proper Requirements of 2008 outlines the categories of fit and proper requirements for FSPs, their key individuals and representatives. The categories of the FAIS Fit and Proper requirements are: - honesty and integrity requirements for FSPs, key individuals and representatives; - competency requirements of FSPs, key individuals and representatives; - experience requirements of FSPs, key individuals and representatives; - qualifications requirements of key individuals and representatives; - regulatory examinations requirements of key individuals and representatives; - continuous professional development requirements of FSPs, key individuals and representatives; - operational ability of FSPs, key individuals and representatives; and - solvency of FSPs. The empirical study of the research was conducted nationally, within South Africa. The focus of the study was to investigate the perception of financial planners with regard to the regulatory and legislative prescriptions of the financial-services industry. The general objective of the study is to provide a quantitative measure of the perception of financial planners of the effect that the legislative and regulatory requirements in South Africa have on the ethicality of the financial-planning industry. To achieve this objective, the empirical study focussed on the responsibilities of financial-services providers and the FAIS fit and proper requirements as set out by the FAIS Act. The population identified for the empirical study consisted of financial planners that provide advisory and/or intermediary services in South Africa. The population of the study consisted of the full advisory complement, 826, which form part of the advisory division of a major South African financial-services provider. These financial planners are located across South Africa, in all nine provinces and in rural and metropolitan areas. Based on the result of the adjusted sample size equation, the required sample size for the study is reduced from 266 to 201. A total of 260 responses were received for the study which ensures a high level of accuracy is achieved from the findings of the research. The results of the empirical study provide ample proof that financial planners support the necessity and specificity of the FAIS fit and proper requirements as defined by the FAIS Act. Additionally, the financial planners agree that the determinants of the FAIS Act are not only beneficial to the sustainability and ethicality of the industry, but also support the success of the planner and ultimately ensure that clients receive the best possible financial advisory and/or intermediary services. / MBA, North-West University, Potchefstroom Campus, 2015
18

Utveckling av produktprototyp för sortering av hushållsavfall / Development of a product prototype for sorting of household waste

Hamrin, Hamrin January 2015 (has links)
Abstract Embedded systems are involved more and more into our daily lives thanks to the concept of the Internet of Things (IoT). An important step in this development is the communication between the systems that been used. The possibilities of sending data in a compressed format based on a protocol standard and use a server with built-in functions, can be a good basis for complex system solutions constructed in Internet of Things (IoT). The simple protocol Messages Queue Telemetry Transport (MQTT) is described to be a protocol that minimizes any bottlenecks in the Machine - To - Machine (M2M) communications while it offers a number of implementing security solutions as data encryption, unique user credentials (username and password) And authentication thereof, and three different Quality of Service (QoS) levels since the data is transmitted over TCP / IP. Along with this server solution is examined in this report, the ability to implement the protocol in a real communication between the development board and an Android mobile application, where the data handled by the broker HiveMQ and stored in a MySQL database and then transferred via a web server to the mobile application. The purpose of the report is therefore to examine the implementations possibility for MQTT in a real scenario with the broker HiveMQ. Where the project resulted in a complete communications solution that corresponds to the protocol can be implemented as well as a theoretical explanation of the security solutions that can be taken to and how well the protocol can scale in a theoretical example. During the work, the development board CC3200 LaunchPad used as target platform. Keywords: CC3200 LaunchPad, HiveMQ, Broker, SQL, Android
19

Αυτοματοποιημένη διαχείριση υπηρεσιών quality of service / Automatic Management of Quality of Service

Πρίμπας, Δημήτριος 27 March 2008 (has links)
Η συνεχής εξέλιξη των δικτύων που βασίζονται στο ΙΡ πρωτόκολλο και η ευρύτατη διάδοση και χρήση τους τα τελευταία χρόνια σε ολόκληρο τον κόσμο καθοδηγεί την ανάγκη για την ανάπτυξη νέων τεχνολογιών και την αναβάθμιση των υπαρχόντων, προκειμένου να καλυφθούν οι συνεχώς μεταβαλλόμενες τάσεις και ανάγκες. Δύο από τις βασικότερες εξελίξεις που σχετίζονται με το επίπεδο του ΙΡ πρωτοκόλλου είναι η δυνατότητα για την παροχή εγγυήσεων ποιότητας (Quality of Service) σε τμήμα της συνολικής κίνησης που διακινείται μέσα από τα ΙΡ δίκτυα, καθώς και η ανάγκη αναβάθμισης του IPv4 πρωτοκόλλου προκειμένου (κυρίως) να εξαλειφθεί το πρόβλημα της φειδωλής διάθεσης μοναδικών και οικουμενικά δρομολογήσιμων διευθύνσεων, καθώς και να βελτιωθούν άλλες δευτερεύουσες ατέλειες του IPv4. Κεντρικό αντικείμενο αυτής της Διδακτορικής Διατριβής αποτελεί η μελέτη των τεχνολογιών για παροχή Quality of Service καθώς και 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, οι οποίες μελετώνται στην εργασία αυτή, ενώ προτείνονται αλγόριθμοι και μηχανισμοί για τη βελτίωση της λειτουργίας και της απόδοσής τους. Επίσης, από το RFC 2638 της IETF έχει οριστεί η μονάδα του Bandwidth Broker που διαχειρίζεται συνολικά υπηρεσίες QoS σε ένα domain. 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 διδακτορικής αυτής διατριβής μελετήθηκε η αρχιτεκτονική DiffServ σε επίπεδο μηχανισμών χρησιμοποιώντας εργαλεία εξομοίωσης (NS-2 simulator) καθώς και πραγματικό δίκτυο ευρείας κλίμακας. Το IPv4 πρωτόκολλο έχει τη δυνατότητα υλοποίησης μηχανισμών QoS στο επίπεδο δικτύου με τη χρήση του πεδίου TOS (Type Of Service). 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. Το αποτέλεσμα ήταν ο σχεδιασμός μιας ομάδας υπηρεσιών QoS (απόλυτης προτεραιότητας σε IP κίνηση, εγγυημένου εύρους ζώνης για L2 συνδέσεις μέσω ιδεατών δικτύων καθώς και κίνησης χαμηλής προτεραιότητας). Ο σχεδιασμός αυτός ολοκληρώθηκε με την υλοποίηση μιας πλήρους εφαρμογής bandwidth broker (κεντρικοποιημένη αρχιτεκτονική) που εκτελεί τις ακόλουθες εργασίες: μοντελοποίηση δικτύου, εφαρμογή του μοντέλου διαστασιολόγησης στην τρέχουσα κατάσταση, αποδοχή κλήσης QoS αιτημάτων, παραγωγή παραμέτρων ρύθμισης για τις δικτυακές συσκευές, παρακολούθηση λειτουργίας QoS στο δίκτυο, επικοινωνία με αντίστοιχους bandwidth brokers σε γειτονικά domains και πλήρη διαχείριση των αιτημάτων QoS. Επιπλέον, δεδομένου ότι οι ανάγκες των εφαρμογών για QoS αυξάνονται, πρέπει να δίνεται μεγαλύτερη ευελιξία μια QoS σηματοδοσία. Για το λόγο αυτό μελετήθηκε και υλοποιήθηκε μια εφαρμογή αυτόματης σηματοδοσίας χρησιμοποιώντας το ευρέως γνωστό πρωτόκολλο δρομολόγησης BGP. Το αποτέλεσμα είναι να επιτυγχάνεται δυναμική σηματοδοσία για QoS σε ένα δίκτυο μέσω μιας διεπαφής που βασίζεται σε Web service ή σε μια Βάση Δεδομένων. Το σύνολο της εργασίας αυτής δοκιμάστηκε και εφαρμόστηκε στο Εθνικό Δίκτυο Έρευνας & Τεχνολογίας και είναι διαθέσιμο σε αντίστοιχα ερευνητικά εθνικά δίκτυα. Επιπλέον, μια 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. Ο υλοποιημένος bandwidth broker επεκτάθηκε ώστε μέσω Web service διεπαφών να «συνομιλεί» με αντίστοιχους άλλων domains. Παράλληλα, στα πλαίσια της εργασίας αυτής ασχοληθήκαμε επίσης με κατανεμημένες αρχιτεκτονικές bandwidth broker όπου έγιναν υλοποιήσεις σε επίπεδο εξομοίωσης. Αρχικά υλοποιήθηκαν ή επεκτάθηκαν οι υλοποιήσεις των μηχανισμών QoS στον εξομοιωτή και δημιουργήθηκε και δοκιμάστηκαν QoS σενάρια. Στη συνέχεια υλοποιήθηκαν παραλλαγές bandwidth broker που ακολουθούσαν κεντρικοποιημένες και κατανεμημένες αρχιτεκτονικές. Στόχος της μελέτης ήταν να μελετηθεί το trade-off στη λειτουργία τους και να συσχετιστεί με τις εκάστοτε δικτυακές συνθήκες. Στην κατανεμημένη λειτουργία εξαρτάται σημαντικά από την τοπολογία του δικτύου, από την διαμόρφωση του bandwidth broker πάνω στη τοπολογία και από την κατανομή QoS αιτημάτων. Για το τελευταίο μελετήθηκε ένας αλγόριθμος προσαρμογής ενός κατανεμημένου bandwidth broker ώστε να επιλέγεται η βέλτιστη διαμόρφωσή του στο δίκτυο (με βάση τις συνθήκες δικτύου) με στόχο την ταχύτερη απόκριση. Τέλος, στα πλαίσια της εργασίας αυτής διερευνήθηκε το θέμα της «inter domain» δρομολόγησης σε μια πλήρη τοπολογία ανεξάρτητων – αυτόνομων domains για την εξεύρεση του βέλτιστου μονοπατιού που ικανοποιεί τις QoS απαιτήσεις. Ειδικότερα , μελετήθηκαν διάφορα μοντέλα και δοκιμάστηκαν πειραματικά σε επίπεδο εξομοίωσης, δίνοντας έμφαση σε θέματα αυτονομίας διαχείρισης στο εσωτερικό κάθε ανεξάρτητου domain και στην τήρηση των SLAs μεταξύ γειτονικών domains. / The main goal of this dissertation is the study of the provisioning of Quality of Service guarantees to part of the total traffic traversing ΙΡ networks. The study is focused on both IPv4 and IPv6 protocol, as IPv6 overcome the limitation that IPv4 has introduced. 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 studied a full QoS framework, including priority and assured bandwidth services for Greek Research and Technology Network. In addition, we studied and implemented a bandwidth broker that manages these services in the above network and it also communicate with adjacent domains (like Geant, the Pan-European Academic Network), providing end-to-end provisioning. The implemented bandwidth broker is based on open source tools and belongs to Grnet’s production services portfolio. Finally, it is available for use to other Research networks as well as the experience from the development. Additionally, we studied distributed architectures of bandwidth brokers using simulation tools. We implemented some enhancements on NS-2 simulator in order to have all the necessary tools for QoS tests and measurements. Next, we simulated and compared distributed and centralized models, focusing on the trade-off in their operation related to the network conditions. In distributed architectures, the operation is highly affected by topology and the distribution of service’s requests. Therefore, we studied an algorithm that adapts the distributed bandwidth broker according to several conditions, by changing the location of the main base station and the overall configuration. Finally, we studied several models for the inter-domain routing in a topology with many independent autonomous systems, aiming at investigate the best routing path that provides the QoS guarantees while the autonomous systems keeps the privacy and the SLAs in their domains.
20

Scheduling distributed data-intensive applications on global grids

Venugopal, Srikumar Unknown Date (has links) (PDF)
The next generation of scientific experiments and studies are being carried out by large collaborations of researchers distributed around the world engaged in analysis of huge collections of data generated by scientific instruments. Grid computing has emerged as an enabler for such collaborations as it aids communities in sharing resources to achieve common objectives. Data Grids provide services for accessing, replicating and managing data collections in these collaborations. Applications used in such Grids are distributed data-intensive, that is, they access and process distributed datasets to generate results. These applications need to transparently and efficiently access distributed data and computational resources. This thesis investigates properties of data-intensive computing environments and presents a software framework and algorithms for mapping distributed data-oriented applications to Grid resources. (For complete abstract open document)

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