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On the Consistency, Characterization, Adaptability and Integrity of Database Replication SystemsRuiz Fuertes, María Idoia 30 September 2011 (has links)
Desde la aparición de las primeras bases de datos distribuidas hasta los actuales sistemas de
replicación modernos, la comunidad de investigación ha propuesto múltiples protocolos para
administrar la distribución y replicación de datos, junto con algoritmos de control de concurrencia
para manejar las transacciones en ejecución en todos los nodos del sistema. Muchos protocolos están
disponibles, por tanto, cada uno con diferentes características y rendimiento, y garantizando
diferentes niveles de coherencia. Para saber qué protocolo de replicación es el más adecuado, dos
aspectos deben ser considerados: el nivel necesario de coherencia y aislamiento (es decir, el criterio
de corrección), y las propiedades del sistema (es decir, el escenario), que determinará el rendimiento
alcanzable.
Con relación a los criterios de corrección, la serialización de una copia es ampliamente aceptada
como el más alto nivel de corrección. Sin embargo, su definición permite diferentes interpretaciones
en cuanto a la coherencia de réplicas. En esta tesis se establece una correspondencia entre los modelos
de coherencia de memoria, tal como se definen en el ámbito de la memoria compartida distribuida, y
los posibles niveles de coherencia de réplicas, definiendo así nuevos criterios de corrección que
corresponden a las diferentes interpretaciones identificadas sobre la serialización de una copia.
Una vez seleccionado el criterio de corrección, el rendimiento alcanzable por un sistema depende en
gran medida del escenario, es decir, de la suma del entorno del sistema y de las aplicaciones que se
ejecutan en él. Para que el administrador pueda seleccionar un protocolo de replicación apropiado, los
protocolos disponibles deben conocerse plena y profundamente. Una buena descripción de cada
candidato es fundamental, pero un marco común es imperativo para comparar las diferentes opciones
y estimar su rendimiento en un escenario dado. Los resultados presentados en esta tesis cumplen los objetivos establecidos y
constituyen una contribución al estado del arte de la replicación de bases de datos
en el momento en que se iniciaron los trabajos respectivos. Estos resultados son
relevantes, además, porque abren la puerta a posibles contribuciones futuras. / Ruiz Fuertes, MI. (2011). On the Consistency, Characterization, Adaptability and Integrity of Database Replication Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11800 / Palancia
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Design for Addressing Data Privacy Issues in Legacy Enterprise Application IntegrationMeddeoda Gedara, Kavindra Kulathilake January 2019 (has links)
Electronic message transfer is the key element in enterprise application integration (EAI) and the privacy of data transferred must be protected by the systems involved in the message transfer from origin to the destination. The recent data privacy regulation such as GDPR (General Data Protection Regulation) has enforced the organizations to ensure the privacy of the personal data handled with obligations to provide visibility and control over to the data owner. Privacy concerns with relevant to sensitive data embedded and transferred through business-to-business (B2B) middleware platforms in enterprise architecture are mostly at risk with the legacy nature of the products and the complexity of system integrations. This poses a great threat and challenge to organizations processing sensitive data over the interconnected systems in complying with regulatory requirements. This research proposes a solution design to address the data privacy issues related to personal data handled in an enterprise application integration framework. Where electronic messages used to transfer personally identifiable information (PII). The proposal consisting of a design called “Safety Locker” to issue unique tokens related to encrypted PII elements stored in a persistence data storage based on Apache Ignite. While adding REST API interfaces to access the application functionality such as tokenization, de-tokenization, token management and accessing audit logs. The safety locker can run as a standalone application allowing clients to access its functionality remotely utilizing hypertext transfer protocol (HTTP). The design allows the data controllers to ensure the privacy of PII by embedding tokens generated from the application within the electronic messages transferred through interconnected systems. The solution design is evaluated through a proof of concept implementation, which can be adapted, enhanced to apply in EAI implementations.
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Distribuovaný informační systém malé firmy / Distributed Information System for a Small FirmPajgrt, Ondřej January 2010 (has links)
This thesis deals with implementation of distributed information systém for a small construction engineering firm all the way from design to deployment. We will be introduced to distributed applications problems and technologies involved either throught direct relevance or as a support tool for the implementation of the project. In addition, this work will guide us throught complete design and implementation of a final product.
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Modell eines virtuellen Finanzdienstleisters: Der Forschungsprototyp cofis.net 1Fettke, Peter, Thießen, Friedrich, Zwicker, Jörg 26 April 2001 (has links)
Zur Zeit sieht sich die Finanzdienstleistungswirtschaft vielfältigen technologischen sowie wirtschaftlichen Entwicklungen gegenüber. Virtuelle Finanzdienstleister sind ein Ansatz, um diesen Entwicklungen gerecht zu werden. In der Literatur wird das Konzept des Virtuellen Finanzdienstleisters nicht einheitlich beschrieben. Es werden fünf Sichtweisen unterschieden: Virtual-Reality-Technologien, Finanzmanagementsoftware, Marketingmix, elektronischer Marktplatz sowie Virtuelle Organisation. An der Fakultät für Wirtschaftswissenschaften der Technischen Universität Chemnitz wurde von den Professuren Wirtschaftsinformatik II sowie Finanzwirtschaft und Bankbetriebslehre ein Modell eines Virtuellen Finanzdienstleisters konzipiert, entworfen und implementiert. Der entwickelte Prototyp cofis.net implementiert zur Zeit das Produkt Virtuelle Überweisung. Das Fach-, DV- sowie Implementierungskonzept des Prototyps wird in dieser Arbeit vorgestellt. Der Prototyp basiert auf einer 5-stufigen Schichtenarchitektur. Die gewählte Architektur konnte realisiert werden. Es verbleiben zahlreiche weiterführende Fragen bspw. hinsichtlich der Gestaltung des Produktmanagement-Zyklus eines Virtuellen Finanzdienstleisters oder der allgemeinen informationstechnischen Abbildbarkeit von Finanzprodukten.
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cofis.net - Ein Informationssystem für Virtuelle FinanzdienstleisterFettke, Peter, Loos, Peter, Thießen, Friedrich 24 September 2001 (has links)
Zur Zeit sieht sich die Finanzdienstleistungswirtschaft vielfältigen technologischen sowie wirtschaftlichen Entwicklungen gegenüber. Virtuelle Finanzdienstleister sind ein Ansatz, um diesen Entwicklungen gerecht zu werden. In der Literatur wird das Konzept des Virtuellen Finanzdienstleisters nicht einheitlich beschrieben. Es werden fünf Sichtweisen unterschieden: Virtual-Reality-Technologien, Finanzmanagementsoftware, Marketingmix, elektronischer Marktplatz sowie Virtuelle Organisation. An der Fakultät für Wirtschaftswissenschaften der Technischen Universität Chemnitz wurde von den Professuren Wirtschaftsinformatik II sowie Finanzwirtschaft und Bankbetriebslehre ein Modell eines Virtuellen Finanzdienstleisters konzipiert, entworfen und implementiert.
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Java in eingebetteten SystemenGatzka, Stephan 17 June 2009 (has links)
Moderne, objektorientierte Sprachen spielen bei der Entwicklung von
Software für eingebettete Systeme bislang kaum eine Rolle. Die Gründe
hierfür sind vielfältig, meist wird jedoch die mangelnde Effizienz und
der größere Speicherbedarf hervorgehoben.
Obwohl Java viele Eigenschaften hat, die sehr für einen Einsatz in
eingebetteten Systemen sprechen, so hängt doch gerade Java vielfach
immer noch das Vorurteil an, in Systemen mit beschränkter Rechenleistung
und Speicher zu viele Ressourcen zu benötigen.
Diese Arbeit soll dazu beitragen, diese Vorurteile abzutragen. Sie
stellt insbesondere Techniken vor, die den Speicherbedarf einer
JVM so gering wie möglich halten und diese effizient mit der zur
Verfügung stehenden Rechenleistung umgehen lassen. Viele der
dargestellten Verfahren und Algorithmen wurden in der Kertasarie
VM implementiert, einer virtuellen Maschine, die speziell für den
Einsatz in eingebetteten Systemen konzipiert wurde.
Durch die weit verbreitete Vernetzung eingebetteter Systeme über das
Internet stellt sich in vielen Fällen zudem das Problem einer modernen,
abstrakten und effizienten Form der Kommunikation. Aus diesem Grund
liegt der zweite Schwerpunkt dieser Arbeit auf dem Vergleich von
objektorientierten Middleware-Architekturen, insbesondere von
Java-RMI. Auch auf diesem Gebiet wird eine eigene, speziell an
eingebettete Systeme angepasste RMI-Variante vorgestellt. / Modern, object oriented languages do not play an important role when developing software for embedded systems. There are many reasons for it, most often an inadequate performance and a greater memory demand are mentioned. In spite of the fact that Java has many features suitable for embedded systems, Java often faces the prejudice to consume too much resources in systems with limited processing power and memory. This work is a contribution to diminish this prejudices. It presents techniques to limit the memory demands of a Java Virtual Machine and to effectively cope with limited computing power. Many of the presented methods and algorithms are implemented in the Kertasarie VM, a JVM designed to run in embedded systems.Due to the fact of increasing network capabilities embedded systems often face the problem of a modern, abstract and efficient communication. Therefore the second emphasis of this work is put on the comparison of object oriented middleware architectures, especially Java-RMI. An own implementation for embedded systems is also presented.
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Development of Generic Communication Middleware for Embedded Sensor Systems Transmitting Health ParametersKailayanathan, Subaharan, Kamdod, Saji January 2020 (has links)
Health technology or e-Health is one of the most rapidly growing areas in healthcare today and it has been an important requirement as a new concept of healthcare industry. Since global society has been changed to aging society and the healthcare cost has been increasing in the 21st century since 2007. As the total number of people aged 65 or older is expected to increase from 12% to 22% in 2050 which is double the rate, and at the same time there is a decrease in in-fertility rates and increase in life expectancy due to the increase in life quality, there is a need to investigate the needs and requirements of an intelligent embedded sensor systems in health applications, and to develop a new communication protocol or set of protocols that can be used to send data collected from a hub within a house, home-care or a complex and send it securely and reliably to a central database where the gathered data can be monitored by a medical professional to make decisions for further interventions. The employed communication protocol should also be able to securely transmit confidential parameters from the hospital network to a central server outside of the hospital network. The final protocol must be inline with the regulations of the EU. This thesis is done in collaboration with Tjeders AB, Stille AB, and Embedded Sensor Systems for Health Plus (ESS-H+) research profile at Mälardalen University. In this thesis, different communication protocols such as IPSec and TLS and algorithms such as AES and RSA are examined and based on the requirements provided by the companies certain of these protocols and algorithms will be used in the final implementation. Different performance metrics such as overhead, round trip delay and throughput will be measured for the chosen communication protocols and recommendations will be given on which of the protocols and algorithms needs to be used to obtain an optimized, secure and reliable network.
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Comparing message-oriented middleware for financial assets trading / Jämförelse av meddelandeorienterade mellanprogramvaror för värdepappershandelEriksson, John January 2016 (has links)
Many different message-oriented middlewares (MOM) exist today on the market. With different underlying designs, purposes and features, it is not easy to make the right choice of MOM for your system. The IT company Nordicstation is in such a situation where they need to make a choice of MOM. They currently own a system called Sharelock which generates reports about violations of financial assets trad- ing. They wish to make the process of generating a report more asynchronous by using a MOM and they have a couple of requirements. This thesis was carried out with the purpose of finding the most suitable products for the system in mind, compare their features, performance, licenses and ease-of- use. This was accomplished by analysing their installation process, monitoring in- terfaces, documentation on their websites and performance in a simple throughput test. The results showed that RabbitMQ was the strongest candidate. It had good per- formance, an attractive web interface for monitoring, an easy installation and it also offered commercial support. Apache Artemis was also found to be an attractive choice but it did not have a web interface which made it hard to manage the system. / Idag finns det många meddelandebaserade mellanprogramvaror (MOM) på marknaden. Dessa har olika grundläggande designer, syften och kännetecken vilket kan göra det svårt att göra ett bra val av MOM för ett visst system. IT-företaget Nordicstation befinner sig i en sådan situation där de behöver göra ett val av MOM. De har ett system som kallas Sharelock som genererar rapporter om regelbrott in- om värdepappershandeln. De vill göra processen mer asynkron genom att använda en MOM och de har ett antal krav på produkten. Det här examensarbetet utfördes med syftet att hitta de mest passande produkter- na för det tänka systemet, jämföra deras särdrag, prestanda, licenser och anvä- ndarvänlighet. Detta gjordes genom att analysera deras installationsprocess, övervakningsgränssnitt, dokumentation på deras hemsida och prestanda i ett en- kelt prestandatest. Resultaten visade att RabbitMQ var den starkaste kandidaten. Den hade bra prestanda, ett attraktivt webbgränssnitt, en enkel installation och den erbjöd också kommersiell support åt kunder. Apache Artemis var också ett attraktivt val men den hade inget webbgränssnitt vilket gjorde det svårt att övervaka och hantera sys- temet.
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Object Synchronization and Security for Mobile Communications DevicesBorison, Torbjorn January 2001 (has links)
The main objective of this master’s thesis project was to investigate and find solutions to the problem of how to combine the SyncML synchronisation specification with object security and thus protection of personal information, such as contacts and calendar entries in mobile devices. SyncML is a new synchronisation specification agreed upon by major device developers (Ericsson, Palm, Motorola, etc.) and the major synchronisation server developers (Starfish, Puma, fusionOne, etc.). It is independent of transport (HTTP, WSP, or OBEX) platform, operating system, and application and simplifies synchronisation of personal information between dissimilar SyncML supportive devices. SyncML compliant devices are fully capable of synchronising information with a third party operated Internet based server and a desktop computer. This allows us to access, up-date and maintain information independent of Intranets or geographical position. However, synchronising and storing confidential personal information on an third party operated Internet based server entails weaknesses in our personal information security. Even if transport and storage security are used, how secure is the server where this information is stored since this server has the highest probability of being attacked. Can we really trust that an employee or other person with valid appropriated administrators access to the storage facility with the appropriate knowledge, working together with the third party server operator, won’t try to access our stored information? To prevent this, the personal information’s confidentiality must be guaranteed before the information leaves the device. When synchronising and exchanging personal information, the information is often marked according to a specific format. The three de-facto standard PIM formats are: (1) vCard (contact information), (2) vCalendar, and (3) iCalendar (calendar and scheduling information). These formats divide the personal information into properties. Each property is assigned to contain a small piece of the personal information entry (e.g. a telephone number, an e-mail address, the time when the calendar event begins, etc.). Furthermore to preserve the interoperability between different devices given by SyncML, authorised recipients must automatically be able to reverse the encryption process and decrypt the encrypted property value. Therefore general cryptographic formats are used (e.g. CMS, PGP and the newly developed XML Encryption). They add information needed by the recipients (e.g. algorithm used, padding method used on the plain text, etc.), encrypt the plaintext into cipher text, and decrypt the cipher text into plain text given the correct key.
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Adaptive Middleware for Self-Configurable Embedded Real-Time Systems : Experiences from the DySCAS Project and Remaining ChallengesPersson, Magnus January 2009 (has links)
Development of software for embedded real-time systems poses severalchallenges. Hard and soft constraints on timing, and usually considerableresource limitations, put important constraints on the development. Thetraditional way of coping with these issues is to produce a fully static design,i.e. one that is fully fixed already during design time.Current trends in the area of embedded systems, including the emergingopenness in these types of systems, are providing new challenges for theirdesigners – e.g. integration of new software during runtime, software upgradeor run-time adaptation of application behavior to facilitate better performancecombined with more ecient resource usage. One way to reach these goals is tobuild self-configurable systems, i.e. systems that can resolve such issues withouthuman intervention. Such mechanisms may be used to promote increasedsystem openness.This thesis covers some of the challenges involved in that development.An overview of the current situation is given, with a extensive review ofdi erent concepts that are applicable to the problem, including adaptivitymechanisms (incluing QoS and load balancing), middleware and relevantdesign approaches (component-based, model-based and architectural design).A middleware is a software layer that can be used in distributed systems,with the purpose of abstracting away distribution, and possibly other aspects,for the application developers. The DySCAS project had as a major goaldevelopment of middleware for self-configurable systems in the automotivesector. Such development is complicated by the special requirements thatapply to these platforms.Work on the implementation of an adaptive middleware, DyLite, providingself-configurability to small-scale microcontrollers, is described andcovered in detail. DyLite is a partial implementation of the concepts developedin DySCAS.Another area given significant focus is formal modeling of QoS andresource management. Currently, applications in these types of systems arenot given a fully formal definition, at least not one also covering real-timeaspects. Using formal modeling would extend the possibilities for verificationof not only system functionality, but also of resource usage, timing and otherextra-functional requirements. This thesis includes a proposal of a formalismto be used for these purposes.Several challenges in providing methodology and tools that are usablein a production development still remain. Several key issues in this areaare described, e.g. version/configuration management, access control, andintegration between di erent tools, together with proposals for future workin the other areas covered by the thesis. / Utveckling av mjukvara för inbyggda realtidssystem innebär flera utmaningar.Hårda och mjuka tidskrav, och vanligtvis betydande resursbegränsningar,innebär viktiga inskränkningar på utvecklingen. Det traditionellasättet att hantera dessa utmaningar är att skapa en helt statisk design, d.v.s.en som är helt fix efter utvecklingsskedet.Dagens trender i området inbyggda system, inräknat trenden mot systemöppenhet,skapar nya utmaningar för systemens konstruktörer – exempelvisintegration av ny mjukvara under körskedet, uppgradering av mjukvaraeller anpassning av applikationsbeteende under körskedet för att nå bättreprestanda kombinerat med e ektivare resursutnyttjande. Ett sätt att nå dessamål är att bygga självkonfigurerande system, d.v.s. system som kan lösa sådanautmaningar utan mänsklig inblandning. Sådana mekanismer kan användas föratt öka systemens öppenhet.Denna avhandling täcker några av utmaningarna i denna utveckling. Enöversikt av den nuvarande situationen ges, med en omfattande genomgångav olika koncept som är relevanta för problemet, inklusive anpassningsmekanismer(inklusive QoS och lastbalansering), mellanprogramvara och relevantadesignansatser (komponentbaserad, modellbaserad och arkitekturell design).En mellanprogramvara är ett mjukvarulager som kan användas i distribueradesystem, med syfte att abstrahera bort fördelning av en applikation överett nätverk, och möjligtvis även andra aspekter, för applikationsutvecklarna.DySCAS-projektet hade utveckling av mellanprogramvara för självkonfigurerbarasystem i bilbranschen som ett huvudmål. Sådan utveckling försvåras avde särskilda krav som ställs på dessa plattformarArbete på implementeringen av en adaptiv mellanprogramvara, DyLite,som tillhandahåller självkonfigurerbarhet till småskaliga mikrokontroller,beskrivs och täcks i detalj. DyLite är en delvis implementering av konceptensom utvecklats i DySCAS.Ett annat område som får särskild fokus är formell modellering av QoSoch resurshantering. Idag beskrivs applikationer i dessa områden inte heltformellt, i varje fall inte i den mån att realtidsaspekter täcks in. Att användaformell modellering skulle utöka möjligheterna för verifiering av inte barasystemfunktionalitet, men även resursutnyttjande, tidsaspekter och andraicke-funktionella krav. Denna avhandling innehåller ett förslag på en formalismsom kan användas för dessa syften.Det återstår många utmaningar innan metodik och verktyg som är användbarai en produktionsmiljö kan erbjudas. Många nyckelproblem i områdetbeskrivs, t.ex. versions- och konfigurationshantering, åtkomststyrning ochintegration av olika verktyg, tillsammans med förslag på framtida arbete iövriga områden som täcks av avhandlingen. / DySCAS
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