Дисертації з теми "Architecture à base de microservices"
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1
Wang, Yuwei. "Evolution of microservice-based applications : Modelling and dafe dynamic updating." Thesis, Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAS009.
Анотація:
Les architectures à base de microservices permettent de construire des systèmes répartis complexes composés de microservices indépendants. Le découplage et la modularité des microservices facilitent leur remplacement et leur mise à jour de manière indépendante. Depuis l'émergence du développement agile et de l'intégration continue (DevOps et CI/CD), la tendance est aux changements de version plus fréquents et en cours d'exécution des applications. La réalisation des changements de version est effectuée par un processus d'évolution consistant à passer de la version actuelle de l'application à une nouvelle version. Cependant, les coûts de maintenance et d'évolution de ces systèmes répartis augmentent rapidement avec le nombre de microservices.L'objectif de cette thèse est de répondre aux questions suivantes~:Comment aider les ingénieurs à mettre en place une gestion de version unifiée et efficace pour les microservices et comment tracer les changements de version dans les applications à base de microservices ?Quand les applications à base de microservices, en particulier celles dont les activités sont longues, peuvent-elles être mises à jour dynamiquement sans arrêter l'exécution de l'ensemble du système ? Comment la mise à jour doit-elle être effectuée pour assurer la continuité du service et maintenir la cohérence du système ?En réponse à ces questions, cette thèse propose deux contributions principales. La première contribution est constituée de modèles architecturaux et d'un graphe d'évolution pour modéliser et tracer la gestion des versions des microservices. Ces modèles sont construits lors de la conception et utilisés durant l'exécution. Cette contribution aide les ingénieurs à abstraire l'évolution architecturale afin de gérer les déploiements lors d'une reconfiguration, et fournit la base de connaissances nécessaire à un intergiciel de gestion autonomique des activités d'évolution. La deuxième contribution est une approche basée sur les instantanés pour la mise à jour dynamique (DSU) des applications à base de microservices. Les instantanés répartis cohérents de l'application en cours d'exécution sont construits pour être utilisés dans la spécification de la continuité du service, l'évaluation des conditions de mise à jour sûre et dans la mise en œuvre des stratégies de mise à jour. La complexité en nombre de messages de l'algorithme DSU n'est alors pas égale à la complexité de l'application répartie, mais correspond à la complexité de l'algorithme de construction d'un instantané réparti cohérentMicroservice architectures contribute to building complex distributed systems as sets of independent microservices. The decoupling and modularity of distributed microservices facilitates their independent replacement and upgradeability. Since the emergence of agile DevOps and CI/CD, there is a trend towards more frequent and rapid evolutionary changes of the running microservice-based applications in response to various evolution requirements. Applying changes to microservice architectures is performed by an evolution process of moving from the current application version to a new version. The maintenance and evolution costs of these distributed systems increase rapidly with the number of microservices.The objective of this thesis is to address the following issues: How to help engineers to build a unified and efficient version management for microservices and how to trace changes in microservice-based applications? When can microservice-based applications, especially those with long-running activities, be dynamically updated without stopping the execution of the whole system? How should the safe updating be performed to ensure service continuity and maintain system consistency?In response to these questions, this thesis proposes two main contributions. The first contribution is runtime models and an evolution graph for modelling and tracing version management of microservices. These models are built at design time and used at runtime. It helps engineers abstract architectural evolution in order to manage reconfiguration deployments, and it provides the knowledge base to be manipulated by an autonomic manager middleware in various evolution activities. The second contribution is a snapshot-based approach for dynamic software updating (DSU) of microservices. The consistent distributed snapshots of microservice-based applications are constructed to be used for specifying continuity of service, evaluating the safe update conditions and realising the update strategies. The message complexity of the DSU algorithm is not the message complexity of the distributed application, but the complexity of the consistent distributed snapshot algorithm
2
Johansson, Gustav. "Investigating differences in response time and error rate between a monolithic and a microservice based architecture." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264840.
Анотація:
With great advancements in cloud computing, the microservice architecture has become a promising architectural style for enterprise software. It has been proposed to cope with problems of the traditional monolithic architecture which includes slow release cycles, limited scalability and low developer productivity. Therefore, this thesis aims to investigate the affordances and challenges of adopting microservices as well as the difference in performance compared to the monolithic approach at one of Sweden’s largest banks, SEB - the Scandinavian Individual Bank. The investigation consisted of a literature study of research papers and official documentation of microservices. Moreover, two applications were developed and deployed using two different system architectures - a monolithic architecture and a microservice architecture. Performance tests were executed on both systems to gather quantitative data for analysis. The two metrics investigated in this study were response time and error rate. The results indicate the microservice architecture has a significantly higher error rate but a slower response time than the monolithic approach, further strengthening the results of Ueda et. al. [47] and Villamizar et. al. [48]. The findings have then been discussed with regards to the challenges and complexity involved in implementing distributed systems. From this study, it becomes clear the complexity shifts from inside the application out towards infrastructure with a microservice architecture. Therefore, microservices should not be seen as a silver bullet. Rather, the type of architecture is highly dependent on the scope of the project and the size of the organization.Med stora framstegen inom molntjänster har microservice arkitekturen kommit att bli en lämplig kandidat för utveckling av företagsprogramvara. Denna typ av systemarkitektur har föreslagits att lösa de problem som den traditionella monolitiska arkitekturen medför; långsamma lanseringar, begränsad skalbarhet och låg produktivitet. Således fokuserar denna avhandling på att utforska de möjligheter samt utmaningar som följer vid adoptering av microservices samt skillnaden i prestanda jämfört med den monolitiska arkitekturen. Detta undersöktes på en av Sveriges största banker, SEB, den Skandinaviska Enskilda Banken. Utredningen bestod av en litteraturstudie av vetenskapliga artiklar samt officiell dokumentation för microservices. Dessutom utvecklades och lanserades två applikationer byggt med två olika typer av systemarkitektur - en som monolitisk arkitektur och den andra som en microservice arkitektur. Prestandatest utfördes sedan på båda systemen för att samla kvantitativ data för analys. De två nyckelvardena som undersöktes i denna studie var responstid och felfrekvens. Resultaten indikerar att microservice arkitekturen har en signifikant högre felfrekvens men en långsammare responstid än den monolitiska arkitekturen, vilket stärker resultaten av Ueda et. al. [47] och Villamizar et. al. [48]. Forskningsresultaten har diskuterats med hänsyn till den komplexitet och de utmaningar som följer vid implementering av distribuerade system. Från denna studie blir det tydligt att komplexiteten i en microservice arkitektur skiftar från inuti applikationen ut till infrastrukturen. Således borde microservices inte ses som en silverkula. Istället är valet av systemarkitektur strikt beroende på omfattningen av projektet samt storleken på organisationen i fråga.
3
Black, Alofi S. "eHealth-as-a-Service: A service based design approach for large scale eHealth architecture." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/119154/1/Alofi_Black_Thesis.pdf.
Анотація:
This thesis is an in-depth exploration of a multi-methodological design science approach to develop a purposeful eHealth-as-a-Service (eHaaS) design artifact, with potential to improve information quality in primary care settings. This was achieved by first, deriving abstract meta-requirements from an ethnographic examination of care pathways to establish the technical goals of the solution. Then, defining the functions, organization, and structure of an eHaaS conceptual model as an example of how service-based architectures might deliver high quality information services. Finally, establishing the validity of the conceptual model with the development of a novel evaluation strategy to explain the predicted change produced by eHaaS architecture. Given that, eHaas provides the foundation for developing a link between the patient and their information that is available to multiple healthcare professionals when needed.
4
Islam, J. (Johirul). "Container-based microservice architecture for local IoT services." Master's thesis, University of Oulu, 2019. http://jultika.oulu.fi/Record/nbnfioulu-201906072492.
Анотація:
Abstract. Edge services are needed to save networking and computational resources on higher tiers, enable operation during network problems, and to help limiting private data propagation to higher tiers if the function needing it can be handled locally. MEC at access network level provides most of these features but cannot help when access network is down. Local services, in addition, help alleviating the MEC load and limit the data propagation even more, on local level. This thesis focuses on the local IoT service provisioning. Local service provisioning is subject to several requirements, related to resource/energy-efficiency, performance and reliability.
This thesis introduces a novel way to design and implement a Docker container-based micro-service system for gadget-free future IoT (Internet of Things) network. It introduces a use case scenario and proposes few possible required micro-services as of solution to the scenario. Some of these services deployed on different virtual platforms along with software components that can process sensor data providing storage capacity to make decisions based on their algorithm and business logic while few other services deployed with gateway components to connect rest of the devices to the system of solution. It also includes a state-of-the-art study for design, implementation, and evaluation as a Proof-of-Concept (PoC) based on container-based microservices with Docker. The used IoT devices are Raspberry Pi embedded computers along with an Ubuntu machine with a rich set of features and interfaces, capable of running virtualized services.
This thesis evaluates the solution based on practical implementation. In addition, the thesis also discusses the benefits and drawbacks of the system with respect to the empirical solution. The output of the thesis shows that the virtualized microservices could be efficiently utilized at the local and resource constrained IoT using Dockers. This validates that the approach taken in this thesis is feasible for providing such services and functionalities to the micro
5
Selmadji, Anfel. "From monolithic architectural style to microservice one : structure-based and task-based approaches." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS026/document.
Анотація:
Les technologies logicielles ne cessent d'évoluer pour faciliter le développement, le déploiement et la maintenance d'applications dans différents domaines. En parallèle, ces applications évoluent en continu pour garantir une bonne qualité de service et deviennent de plus en plus complexes. Cette évolution implique souvent des coûts de développement et de maintenance de plus en plus importants, auxquels peut s'ajouter une augmentation des coûts de déploiement sur des infrastructures d'exécution récentes comme le cloud. Réduire ces coûts et améliorer la qualité de ces applications sont actuellement des objectifs centraux du domaine du génie logiciel. Récemment, les microservices sont apparus comme un exemple de technologie ou style architectural favorisant l'atteinte de ces objectifs.Alors que les microservices peuvent être utilisés pour développer de nouvelles applications, il existe des applications monolithiques (i.e., monolithes) cons-truites comme une seule unité et que les propriétaires (e.g., entreprise, etc.) souhaitent maintenir et déployer sur le cloud. Dans ce cas, il est fréquent d'envisager de redévelopper ces applications à partir de rien ou d'envisager une migration vers de nouveaux styles architecturaux. Redévelopper une application ou réaliser une migration manuellement peut devenir rapidement une tâche longue, source d'erreurs et très coûteuse. Une migration automatique apparaît donc comme une solution évidente.L'objectif principal de notre thèse est de contribuer à proposer des solutions pour l'automatisation du processus de migration d'applications monolithiques orientées objet vers des microservices. Cette migration implique deux étapes : l'identification de microservices et le packaging de ces microservices. Nous nous focalisons sur d'identification en s'appuyant sur une analyse du code source. Nous proposons en particulier deux approches.La première consiste à identifier des microservices en analysant les relations structurelles entre les classes du code source ainsi que les accès aux données persistantes. Dans cette approche, nous prenons aussi en compte les recommandations d'un architecte logiciel. L'originalité de ce travail peut être vue sous trois aspects. Tout d'abord, les microservices sont identifiés en se basant sur l'évaluation d'une fonction bien définie mesurant leur qualité. Cette fonction repose sur des métriques reflétant la "sémantique" du concept "microservice". Deuxièmement, les recommandations de l'architecte logiciel ne sont exploitées que lorsqu'elles sont disponibles. Enfin, deux modèles algorithmiques ont été utilisés pour partitionner les classes d'une application orientée objet en microservices : un algorithme de regroupement hiérarchique et un algorithme génétique.La deuxième approche consiste à extraire à partir d'un code source orienté objet un workflow qui peut être utilisé en entrée de certaines approches existantes d'identification des microservices. Un workflow décrit le séquencement de tâches constituant une application suivant deux formalismes: un flot de contrôle et/ou un flot de données. L'extraction d'un workflow à partir d'un code source nécessite d'être capable de définir une correspondance entre les concepts du mon-de objet et ceux d'un workflow.Pour valider nos deux approches, nous avons implémenté deux prototypes et mené des expérimentations sur plusieurs cas d'étude. Les microservices identifiés ont été évalués qualitativement et quantitativement. Les workflows obtenus ont été évalués manuellement sur un jeu de tests. Les résultats obtenus montrent respectivement la pertinence des microservices identifiés et l'exactitude des workflows obtenusSoftware technologies are constantly evolving to facilitate the development, deployment, and maintenance of applications in different areas. In parallel, these applications evolve continuously to guarantee an adequate quality of service, and they become more and more complex. Such evolution often involves increased development and maintenance costs, that can become even higher when these applications are deployed in recent execution infrastructures such as the cloud. Nowadays, reducing these costs and improving the quality of applications are main objectives of software engineering. Recently, microservices have emerged as an example of a technology or architectural style that helps to achieve these objectives.While microservices can be used to develop new applications, there are monolithic ones (i.e., monoliths) built as a single unit and their owners (e.g., companies, etc.) want to maintain and deploy them in the cloud. In this case, it is common to consider rewriting these applications from scratch or migrating them towards recent architectural styles. Rewriting an application or migrating it manually can quickly become a long, error-prone, and expensive task. An automatic migration appears as an evident solution.The ultimate aim of our dissertation is contributing to automate the migration of monolithic Object-Oriented (OO) applications to microservices. This migration consists of two steps: microservice identification and microservice packaging. We focus on microservice identification based on source code analysis. Specifically, we propose two approaches.The first one identifies microservices from the source code of a monolithic OO application relying on code structure, data accesses, and software architect recommendations. The originality of our approach can be viewed from three aspects. Firstly, microservices are identified based on the evaluation of a well-defined function measuring their quality. This function relies on metrics reflecting the "semantics" of the concept "microservice". Secondly, software architect recommendations are exploited only when they are available. Finally, two algorithmic models have been used to partition the classes of an OO application into microservices: clustering and genetic algorithms.The second approach extracts from an OO source code a workflow that can be used as an input of some existing microservice identification approaches. A workflow describes the sequencing of tasks constituting an application according to two formalisms: control flow and /or data flow. Extracting a workflow from source code requires the ability to map OO conceptsinto workflow ones.To validate both approaches, we implemented two prototypes and conducted experiments on several case studies. The identified microservices have been evaluated qualitatively and quantitatively. The extracted workflows have been manually evaluated relying on test suites. The obtained results show respectively the relevance of the identified microservices and the correctness of the extracted workflows
6
Braun, Eric [Verfasser]. "Microservice-based Reference Architecture for Semantics-aware Measurement Systems / Eric Braun." Karlsruhe : KIT-Bibliothek, 2020. http://d-nb.info/1222109514/34.
7
Romin, Philip. "Unraveling Microservices : A study on microservices and its complexity." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-290292.
Анотація:
Microservices is one of the most commonly used buzzword of the systems architecture industry and is being adopted by several of the world’s largest technology companies such as Netflix, Uber and Amazon. The architecture which embraces splitting up your system in smaller independent units is an extension of the service-oriented architecture and an opponent of the monolithic architecture. Being a top buzzword and promises of extreme scalability has spiked the interest for microservices, but unlike the relatively simple monolithic architecture the complexity of microservices creates a new set of obstacles. This work sheds a light on these issues and implements solutions for some of the most frequent problems using a case study. The study shows that while microservices can help reduce the inner complexity of a system, it greatly increases the outer complexity and creates the need for a variety of tools aimed at distributed systems. It also concludes that communication and data storage are two of the most frequently occurring issues when developing microservices with the most difficult one being how you reason with and structure your data, especially for efficient queries across microservices.Microservices eller så kallade mikrotjänster är ett ofta förekommande buzzword inom systemarkitektur och nyttjas av flera teknikjättar som exempelvis Netflix, Uber och Amazon. Arkitekturen som bygger på att dela upp sina system i mindre oberoende delar är en utbyggnad av den tjänstorienterade arkitekturen och numera motståndare till den klassiska monolitiska arkitekturen. En plats högt upp på trendlistan och lovord om extrem skalbarhet har gjort att intresset för mikrotjänster är enormt, men till skillnad från den relativt simpla monolitiska arkitekturen skapar komplexiteten hos mikrostjänster en rad nya hinder. Det här arbetet belyser dessa hinder och implementerar även lösningar för de vanligaste förekommande problemen med hjälp av en fallstudie. Resultatet visar att även fast en mikrotjänstarkitektur kan minska systemets interna komplexitet så leder det till en markant ökning av systemets yttre komplexitet och det skapas ytterligare behov av en mängd olika verktyg och tjänster designade för distribuerade system. Studien visar också att de två mest förekommande problemen vid utveckling av en mikrotjänstarkitektur är kommunikation och datalagring där hantering och struktur av data är den mest komplicerade och kräver mycket kunskap, speciellt för att skapa effektiva datasökningar som sträcker sig över flera mikrotjänster.
8
Nhat, Minh Pham. "A proposal for a cloud-based microservice architecture for the Skolrutiner system." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-428348.
Анотація:
Skolrutiner, a fast-moving startup company, has a great idea of aplatform for handling documents. However, they do not have a scalableand modular system architecture since all the current services arecentralized and running on a single virtual machine. The main purposeof this thesis is to study and design a cloud-based microservicesystem for the platform of the company. This new microserviceapproach, with the help of many modern features of cloud computing,is expected to resolve the major issues of the current system. Theproposed architecture might be costly and challenging to implement,but it could help the company to have a general knowledge about cloudcomputing, microservices, and how to apply these technologies to theexpanding business. The re-implementation of the Skolrutiner systembased on the given architecture is out of the scope of this thesiswork.
9
Shafabakhsh, Benyamin. "Research on Interprocess Communication in Microservices Architecture." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277940.
Анотація:
With the substantial growth of cloud computing over the past decade, microservices has gained significant popularity in the industry as a new architectural pattern. It promises a cloud-native architecture that breaks large applications into a collection of small, independent, and distributed packages. Since microservices-based applications are distributed, one of the key challenges when designing an application is the choice of mechanism by which services communicate with each other. There are several approaches for implementing Interprocess communication (IPC) in microservices, and each comes with different advantages and trade-offs. While theoretical and informal comparison exists between them, this thesis has taken an experimental approach to compare and contrast common forms of IPC communications. In this the- sis, IPC methods have been categorized into Synchronous and Asynchronous categories. The Synchronous type consists of REST API and Google gRPC, while the Asynchronous type is using a message broker known as RabbitMQ. Further, a collection of microservices for an e-commerce scenario has been designed and developed using all the three IPC methods. A load test has been executed against each model to obtain quantitative data related to Performance Efficiency, and Availability of every method. Developing the same set of functionalities using different IPC methods has offered a qualitative data related to Scalability, and Complexity of each IPC model. The evaluation of the experiment indicates that, although there is no universal IPC solution that can be applied in all cases, Asynchronous IPC patterns shall be the preferred option when designing the system. Nevertheless, the findings of this work also suggest there exist scenarios where Synchronous patterns can be more suitable.Med den kraftiga tillväxten av molntjänster under det senaste decenniet har mikrotjänster fått en betydande popularitet i branschen som ett nytt arkitektoniskt mönster. Det erbjuder en moln-baserad arkitektur som delar stora applikationer i en samling små, oberoende och distribuerade paket. Eftersom microservicebaserade applikationer distribueras och körs på olika maskiner, är en av de viktigaste utmaningarna när man utformar en applikation valet av mekanism med vilken tjänster kommunicerar med varandra. Det finns flera metoder för att implementera Interprocess-kommunikation (IPC) i mikrotjänster och var och en har olika fördelar och nackdelar. Medan det finns teoretisk och in- formell jämförelse mellan dem, har denna avhandling tagit ett experimentellt synsätt för att jämföra och kontrastera vanliga former av IPC-kommunikation. I denna avhandling har IPC-metoder kategoriserats i synkrona och asynkrona kategorier. Den synkrona typen består av REST API och Google gRPC, medan asynkron typ använder en meddelandemäklare känd som RabbitMQ. Dessutom har en samling mikroservice för ett e-handelsscenario utformats och utvecklats med alla de tre olika IPC-metoderna. Ett lasttest har utförts mot var- je modell för att erhålla kvantitativa data relaterade till prestandaeffektivitet, och tillgänglighet för varje metod. Att utveckla samma uppsättning funktionaliteter med olika IPC-metoder har erbjudit en kvalitativ data relaterad till skalbarhet och komplexitet för varje IPC-modell. Utvärderingen av experimentet indikerar att även om det inte finns någon universell IPC-lösning som kan tillämpas i alla fall, ska asynkrona IPC-mönster vara det föredragna alternativet vid utformningen av systemet. Ändå tyder resultaten från detta arbete också på att det finns scenarier där synkrona mönster är mer lämpliga.
10
Sundberg, Alexander. "A study on load balancing within microservices architecture." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-38902.
Анотація:
This study addresses load balancing algorithms for networked systems with microservices architecture. In microservices applications, functionality and logic have been split into small pieces referred to as services. Such divisions allow for higher levels of scalability and distributivity than obtainable for more classical architectures where functionality and logic is packaged into large non-separable applications. As a first step, we investigate existing load balancing algorithms in the literature. A conclusion reached from this literature survey is that there is a lack of proposed load balancing algorithms for microservices, and it is not obvious how to adapt such algorithms to the architecture under consideration. In particular, many existing algorithms incorporate queues, which should be avoided for microservices, where the small services should be provided in fast manner. Hence, we provide modified and new candidates for load balancing, where one such is a probabilistic approach including a distribution that is a function of service providers' load. The algorithms are implemented in microservices simulation environment developed in Erlang by Ericsson AB. We consider a range of scenarios for evaluation, where amongst other things, we vary the number of service consumers and providers. To evaluate the load balancing algorithms, we perform statistical analysis, where first and second order moments are computed for relevant metrics under the different scenarios considered. A conclusion drawn from the results is that the algorithm referred to as "Round Robin" performed best according to the results from various simulation scenarios. This study serves as a stepping stone for further investigations. We outline several possible extensions such as more in-depth statistical analysis accounting for the time-varying aspects of the systems (currently omitted), as well other classes of algorithms.
11
Eriksson, Mats. "A case study of performance comparison between monolithic and microservice-based quality control system." Thesis, Linköpings universitet, Programvara och system, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166755.
Анотація:
Microservice architecture has emerged as a new way to create large complex applications by removing some problems that exist for a monolithic counterpart. While this will asset agility, resilience, maintainability and scalability within the application, other problems will be predominant such as performance. This case study aims to provide more clarity on this matter by comparing a microservice architecture with a monolithic architecture. By conducting several experiment on two self-developed systems it could be found that microservice architecture will must likely show a lower performance in terms of throughput and latency on HTTP requests which use internal communication requests. On small intensive HTTP requests with minimum internal communication the difference between the architectures is so low it could almost be neglected. With microservice architecture comes other challenges that a company must keep into account such loadbalancing, caching and orchestration which are beneficial for the performance.
12
Buono, Vincenzo, and Petar Petrovic. "Enhance Inter-service Communication in Supersonic K-Native REST-based Java Microservice Architectures." Thesis, Högskolan Kristianstad, Fakulteten för naturvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-22135.
Анотація:
The accelerating progress in network speeds and computing power permitted the architectural design paradigm to shift from monolithic applications to microservices. The industry moved from single-core and multi-threads, code-heavy applications, running on giant machines 24/7 to smaller machines, multi-cores single threads where computing power and memory consumption are managed very critically. With the advent of this novel approach to designing systems, traditional multi-tier applications have been broken down into hundreds of microservices that can be easily moved around, start, and stop quickly. In this context, scaling assumed a new meaning, rather than scaling up by adding more resources or computing power, now systems are scaled dynamically by adding more microservices instances. This contribution proposes a theoretical study and a practical experiment to investigate, compare and outline the performance improvements aid by the implementation of Protocol Buffers, Google's language-neutral, binary-based representational data interchange format over traditional text-based serialization formats in a modern, Cloud-Native, REST-based Java Microservice architecture. Findings are presented showing promising results regarding the implementation of Protobuf, with a significant reduction in response time (25.1% faster in the best-case scenario) and smaller payload size (72.28% better in the best-case scenario) when compared to traditional textual serialization formats while literature revealed out-of-the-box mechanisms for message versioning with backward compatibility.
13
Khan, Asghar. "Microservices in context: Internet of Things : Infrastructure and Architecture." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-90684.
Анотація:
The enterprise systems are built with a monolithic way of software architecture which may not be the very suitable and realistic solutions, due to the quantity and diversity of Internet of Things (IOT) devices connected to the internet. The large code is based as a single deployable unit; making it cumbersome and difficult to change, test, and deploy – typically in the monthly deployment cycles. Which could potentially be a large impact and high-risk for updates and deployment build up between releases. The thesis aims to exploit Microservices Architecture in context of the Internet of Things. Because of scalability and rapid deployment, Microservices Architecture (MSA) naturally fits for M2M and IOT developments. Therefore, it has become increasingly popular and highly suited as a design choice in the context of developing IOT applications. We have proposed various ontologies for conceptual architecture designs. Our conceptual model encompasses all the essential elements and entities that constitute IOT; describing various characteristics of microservices and consideration to be used as a basis for developing a Reference Architecture model. The reference architecture is effectively exploiting Microservices Architectural Style for a diverse set of things composition like sensor devices, connectivity and transportation protocols for IP enabled IOT smart objects. The thesis will contribute to the conceptual space of more successful reference architectures. The goal is to provide features and deployment information with instantiation guidelines to derive the software architecture instances in a given IOT application domain. Thus, it promises to become a valuable framework in the derivation of the Microservices IOT architectures.
14
Leo, Zacharias. "Achieving a Reusable Reference Architecture for Microservices in Cloud Environments." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-44601.
Анотація:
Microservices are a new trend in application development. They allow for breaking down big monolithic applications into smaller parts that can be updated and scaled independently. However, there are still many uncertainties when it comes to the standards of the microservices, which can lead to costly and time consuming creations or migrations of system architectures. One of the more common ways of deploying microservices is through the use of containers and container orchestration platform, most commonly the open-source platform Kubernetes. In order to speed up the creation or migration it is possible to use a reference architecture that acts as a blueprint to follow when designing and implementing the architecture. Using a reference architecture will lead to more standardized architectures, which in turn are most time and cost effective. This thesis proposes such a reference architecture to be used when designing microservice architectures. The goal of the reference architecture is to provide a product that meets the needs and expectations of companies that already use microservices or might adopt microservices in the future. In order to achieve the goal of the thesis, the work was divided into three main phases. First, a questionnaire was conducted and sent out to be answered by experts in the area of microservices or system architectures. Second, literature studies were made on the state of the art and practice of reference architectures and microservice architectures. Third, studies were made on the Kubernetes components found in the Kubernetes documentation, which were evaluated and chosen depending on how well they reflected the needs of the companies. This thesis finally proposes a reference architecture with components chosen according to the needs and expectations of the companies found from the questionnaire.
15
Tipirisetty, Venkat Sivendra. "Performance Analysis of Service in Heterogeneous Operational Environments." Thesis, Blekinge Tekniska Högskola, Institutionen för kommunikationssystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13348.
Анотація:
In recent years there is a rapid increase in demand for cloud services, as cloud computing has become a flexible platform for hosting microservices over the Internet. Microservices are the core elements of service oriented architecture (SOA) that facilitate the deployment of distributed software systems. As the user requires good quality of service the response time of microservices is critical in assessing the performance of the application from the end user perspective.This thesis work aims at developing a typical service architecture to facilitate the deployment of compute and I/O intensive services. The work also aims at evaluating the service times of these service when their respective subservices are deployed in heterogeneous environments with various loads.The research work has been carried out using an experimental testbed in order to evaluate the performance. The transport level performance metric called Response time is measured. It is the time taken by the server to serve the request sent by the client. Experiments have been conducted based on the objectives that are to be achieved.The results obtained from the experimentation contain the average service times of a service when it is deployed on both virtual and non-virtual environment. The virtual environment is provided by Docker containers. They also include the variation in position of their subservices. From results it can be concluded that the total service times obtained are less in case of non-virtual environments when compared to container environment.
16
Muresu, Daniel. "Investigating the security of a microservices architecture : A case study on microservice and Kubernetes Security." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302579.
Анотація:
The concept of breaking down a bigger application into smaller components is not a new idea, but it has been more commonly adopted in recent years due to the rise of the microservice application architecture. What has not been elaborated on enough however, is the security of the microservice architecture and how it differs from a monolithic application architecture. This leads to question what the most relevant security vulnerabilities of integrating and using a microservice architecture are, and what the correlating metrics that can be used to detect intrusions based on the vulnerabilities can be. In this report, the security of the microservice architecture is elaborated on in a case study of the system at Skatteverket, the Swedish tax agency, which is a microservice based architecture running on Kubernetes. Interviews are conducted with people that have experience in Kubernetes and microservices separately, both employed at Skatteverket and elsewhere. In the interviews, vulnerabilities and intrusion detection metrics are identified, which are then analyzed with respect to a use case in the Skatteverket system. A survey is also done on the existing technologies that can mitigate the identified vulnerabilities that are related to a microservice architecture. The vulnerabilities present in the use case are then concluded to be most relevant, the identified intrusion detection metrics are elaborated on and the service mesh technology Istio is found to mitigate largest number of the identified vulnerabilities.Konceptet att bryta ner en större applikation i mindre komponenter är inte en ny idé, men den har blivit vanligare under de senaste åren på grund av växten i användning av mikrotjänstsarkitekturer. Vad som dock inte har utforskats tillräckligt är säkerheten för mikrotjänstarkitekturen och hur den skiljer sig från en monolitisk applikationsarkitektur. Detta leder till att fråga vilka de mest relevanta säkerhetsriskerna med att integrera och använda en mikrotjänstarkitektur är, och vilka mätvärden som kan användas för att upptäcka intrång baserat på riskerna kan vara. I denna rapport utforskas säkerheten för mikrotjänstarkitekturer genom en fallstudie av systemet hos Skatteverket, som är en mikrotjänstbaserad arkitektur som körs på Kubernetes. Intervjuer genomförs med personer som har erfarenhet av Kubernetes och mikrotjänster separat, både med anställda på Skatteverket och på annat håll. I intervjuerna identifieras risker och mätvärden för att märka av intrång som sedan analyseras med avseende på ett användningsfall i Skatteverketssystemet. En undersökning görs också om befintlig teknik som kan mildra de identifierade riskerna som är relaterade till en mikrotjänstarkitektur. De risker som förekommer i användningsfallet anses sedan till att vara mest relevanta i slutsatserna, de identifierade mätvärdena för att märka av intrång diskuteras och service mesh teknologin Istio anses mitigera störst antal av de identifierade riskerna.
17
Habbal, Nadin. "Enhancing Availability of Microservice Architecture : A Case Study on Kubernetes Security Configurations." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79185.
18
Bacchiani, Lorenzo. "Microservice Dynamic Architecture-Level Deployment Orchestration." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21412/.
Анотація:
We develop a novel approach for run-time global adaptation of microservice applications, based on synthesis of architecture-level reconfiguration orchestrations. In particular, we devise an algorithm for automatic reconfiguration that reaches a target system maximum computational load by performing optimal deployment orchestrations. To present our approach we use the high-level object-oriented probabilistic/timed specification language Abstract Behavioral Specification (ABS).With ABS we model microservice applications and virtual machines, we synthesize deployment orchestrations and we simulate them. In particular, we conceive the orchestration language time model so to encompass: microservice deployment time and virtual machine speed based on cpu cores that are actually being used. We evaluate the applicability of our approach on a realistic microservice application taken from the literature: an Email Pipeline Processing System. We show its effectiveness by simulating such an application and by comparing architecture-level reconfiguration with traditional local scaling techniques (detecting scaling needs and enacting replications at the level of single microservices). Our comparison results show that our approach avoids cascading slowdowns and consequent increased message loss and latency that affect traditional local scaling.
19
Ekbjörn, Carl, and Daniel Sonesson. "Collecting Information from a decentralized microservice architecture." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-151828.
Анотація:
As a system grows in size, it is common that it is transformed into a microservice architecture. In order to be able monitor this new architecture there is a need to collect information from the microservices. The software company IDA Infront is transitioning their product iipax to a microservice architecture and is faced with this problem. In order to solve this, they propose the use of a Message-oriented Middleware (MOM). There exists many different MOMs that are suitable to execute this task. The aim of this thesis is to determine, in terms of latency, throughput and scalability, which MOM is best suitable for this. Out of four suitable MOMs Apache Kafka and RabbitMQ are chosen for further testing and benchmarking. The tests display that RabbitMQ is able to send single infrequent messages (latency) faster than Kafka. But it is also shown that Kafka is faster at sending a lot of messages rapidly and with an increased number of producers sending messages (throughput and scalability). However, the scalability test suggests that RabbitMQ possibly scales better with a larger amount of microservices, thus more testing is needed to get a definite conclusion.
20
Holmström, Jesper. "Distributed Queries: An Evaluation of the Microservice Architecture." Thesis, Linköpings universitet, Programvara och system, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166314.
Анотація:
The microservice architecture is a new architectural style that structures an application into a set of small, independently deployable microservices, as opposed to the traditional monolith approach with a single executable. The microservice architecture is a distributed system that results in new challenges and increased complexity. This study expands the previous related research and investigates the implications of using the one-database-per-service pattern and a solution to the introduced need of queries spanning multiple microservices. In this thesis, two applications are presented, one with the microservice architecture and one monolithic counterpart, which are compared in terms of response time and throughput. As a solution for the distributed queries, the API Composition pattern was chosen. The results of the experiments conclude in a greater understanding of the difficulty in distributed queries as well as the benefits and limitations of the API composition pattern. It shows that the API composition pattern is a valid solution for distributed queries. However, it does perform worse in terms of response time and throughput than the monolith prototype. This results in the insights that one must carefully choose, with respect to the requirements of the system, when to apply it.
21
Antonio, Christian, and Björn Fredriksson. "Message brokers in a microservice architecture." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299741.
Анотація:
The microservice architectural pattern refers to a system consisting of independently deployable services that communicate across networks. RabbitMQ is a popular message broker that can be used to make this communication possible. An alternative to this is Amazon Simple Queuing Service (SQS), which is a fully managed queuing service. By performing a literature- and case study, two systems with a microservice architecture are developed. One using RabbitMQ to communicate between the services, and the other using Amazon SQS. The systems are compared, with regards to message latency, ease of use and maintainability. The results show that RabbitMQ provides much lower message latency than Amazon SQS. Amazon SQS is however both easier to maintain and to use than RabbitMQ.En mikrotjänstarkitektur syftar till ett system bestående av tjänster som kan driftsättas oberoende av varandra och som kommunicerar över nätverk. RabbitMQ är en populär meddelandemäklare som nyttjas för att möjliggöra ovan nämnd kommunikation. Ett alternativ till detta är Amazon Simple Queueing Service (SQS), vilket är en meddelandetjänst som helt och hållet förvaltas av Amazon. Genom att utföra en litteratur- och fallstudie utvecklas två system med en mikrotjänstarkitektur. Det ena nyttjar RabbitMQ för kommunikation mellan tjänster, medan det andra använder Amazon SQS. Båda systemen jämförs därefter med hänsyn till meddelandens fördröjning, användarvänlighet samt enkelhet att underhålla. Resultaten visar att meddelanden skickade genom RabbitMQ har mycket lägre fördröjning än de skickade genom Amazon SQS. Ur perspektiven användarvänlighet och enkelhet att underhålla är Amazon SQS ett mer fördelaktigt akternativ än RabbitMQ.
22
Swales, Simon C. "Spectrum efficient cellular base-station antenna architecture." Thesis, University of Bristol, 1990. http://hdl.handle.net/1983/67cf052f-7671-4a49-a971-85207d6b2624.
23
Kinzie, Pamela L. "Inheriting military base property--a public/private approach to reuse implementation : case study of Mather Air Force Base." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/67734.
24
Donnici, Margherita. "Applicazione Jolie - Servizio Prenotazioni." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9096/.
Анотація:
Introduzione sulla service-oriented architecture, i microservices, il linguaggio Jolie e descrizione della progettazione ed implementazione di un'applicazione Jolie service-oriented per la prenotazione di spazi (Booking Service).
25
O'Brien, Stephen T. (Stephen Thomas) 1962. "Military base redevelopment : issues facing private developers." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/69389.
26
Hölscher, Anton. "The Latency Effects of Utilizing a Microservice Architecture in a Time-Critical System." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-178295.
Анотація:
This study aims to examine the effects of transforming a monolithic server system into a microservice architecture, focusing on the increased latency introduced by using a microservice orchestrator. The microservice orchestrator was implemented using an OpenFlow switch controlled by the Beacon and Ryu OpenFlow controllers. These controllers, along with the round robin, random assign and a server-aware load balancing algorithm, were all compared in order to find the combination resulting in the lowest latency and highest achieved server balance in varying network environments. We show that the OpenFlow switch enforces a client-aware load balancing policy and that only the initial request is handled by the controller, effectively reducing the importance of choosing the optimal OpenFlow controller. In addition, the round robin load balancer was preferred when dealing with homogeneous requests, and a server-aware load balancer was required for heterogeneous requests. For most requests, the system would only slow down by a few microseconds using the proposed architecture. However, for 0.001\% of all requests, the slowdown was much more significant, with each of those requests being at least 100 times slower than when using a monolithic server architecture.
27
Mara, Jösch Ronja. "Managing Microservices with a Service Mesh : An implementation of a service mesh with Kubernetes and Istio." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-280407.
Анотація:
The adoption of microservices facilitates extending computer systems in size, complexity, and distribution. Alongside their benefits, they introduce the possibility of partial failures. Besides focusing on the business logic, developers have to tackle cross-cutting concerns of service-to-service communication which now defines the applications' reliability and performance. Currently, developers use libraries embedded into the application code to address these concerns. However, this increases the complexity of the code and requires the maintenance and management of various libraries. The service mesh is a relatively new technology that possibly enables developers staying focused on their business logic. This thesis investigates one of the available service meshes called Istio, to identify its benefits and limitations. The main benefits found are that Istio adds resilience and security, allows features currently difficult to implement, and enables a cleaner structure and a standard implementation of features within and across teams. Drawbacks are that it decreases performance by adding CPU usage, memory usage, and latency. Furthermore, the main disadvantage of Istio is its limited testing tools. Based on the findings, the Webcore Infra team of the company can make a more informed decision whether or not Istio is to be introduced.Tillämpningen av microservices underlättar utvidgningen av datorsystem i storlek, komplexitet och distribution. Utöver fördelarna introducerar de möjligheten till partiella misslyckanden. Förutom att fokusera på affärslogiken måste utvecklare hantera övergripande problem med kommunikation mellan olika tjänster som nu definierar applikationernas pålitlighet och prestanda. För närvarande använder utvecklare bibliotek inbäddade i programkoden för att hantera dessa problem. Detta ökar dock kodens komplexitet och kräver underhåll och hantering av olika bibliotek. Service mesh är en relativt ny teknik som kan möjliggöra för utvecklare att hålla fokus på sin affärslogik. Denna avhandling undersöker ett av de tillgängliga service mesh som kallas Istio för att identifiera dess fördelar och begränsningar. De viktigaste fördelarna som hittas är att Istio lägger till resistens och säkerhet, tillåter funktioner som för närvarande är svåra att implementera och möjliggör en renare struktur och en standardimplementering av funktioner inom och över olika team. Nackdelarna är att det minskar prestandan genom att öka CPU-användning, minnesanvändning och latens. Dessutom är Istios största nackdel dess begränsade testverktyg. Baserat på resultaten kan Webcore Infra-teamet i företaget fatta ett mer informerat beslut om Istio ska införas eller inte.
28
Etchegoyen, Emilio G. "Historical context as it affects the base of the skyscraper." Thesis, Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/24114.
29
van, Dreven Jonne. "Functional Decomposition Techniques and Their Impact on Performance, Scalability and Maintainability." Thesis, Blekinge Tekniska Högskola, Institutionen för datavetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-21876.
Анотація:
Context The last decade shows many solution proposals of functional decomposition techniques to aid in developing microservice architectures. While some solutions may work, it is uncertain what the effects are on quantitative, measurable metrics; thus, the proposals require validation. Objective The study measures the effects of various functional decomposition techniques on performance, scalability, and maintainability. Furthermore, the study will compare the treatments in order to find whether a statistical significance exists. Method The study uses a controlled experiment containing three functional decomposition techniques—Event Storming, Actor/Action, and Service Cutter—applied on the same use case. The use case follows the CoCoMe framework, which forms the basis of the experiment. Results Each treatment shows similar behavior while presenting different architectural designs. The study found no statistical significance for performance, scalability, and maintainability. Conclusion Evidence suggests that the convenience of an approach might be more important than the resulting architecture since they will likely lead to the same outcome. If performance issues arise, it would likely be due to the microservices architecture and not the functional decomposition technique; therefore, the microservices architecture might not equally benefit any situation or corporation. Furthermore, the study found that service granularity might not be as relevant as some studies claim it to be, and other factors could be more crucial.
30
Sass, David John. "The state role in military base closure and reuse." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/70234.
31
Faradj, Rasti. "The run-time impact of business functionality when decomposing and adopting the microservice architecture." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-235800.
Анотація:
In line with the growth of software, code bases are getting bigger and more complex. As a result of this, the architectural patterns, which systems rely upon, are becoming increasingly important. Recently, decomposed architectural styles have become a popular choice. This thesis explores system behavior with respect to decomposing system granularity and external communication between the resulting decomposed services. An e-commerce scenario was modeled and implemented at different granularity levels to measure the response time. In establishing the communication, both REST with HTTP and JSON and the gRPC framework were utilized. The results showed that decomposition has impact on run-time behaviour and external communication. The highest granularity level implemented with gRPC for communication establishment adds 10ms. In the context of how the web behaves today, it can be interpreted as feasible but there is no discussion yet on whether it is theoretically desirable.I linje med de växande mjukvarusystemen blir kodbaserna större och mer komplexa. Arkitekturerna som systemen bygger på får allt större betydelse. Detta examensarbete utforskar hur upplösning av system som tillämpar mikroservicearkitektur beter sig, och hur de påverkas av kommunikationsupprättande bland de upplösta och resulterande tjänsterna. Ett e-handelsscenario modelleras i olika granularitetsnivåer där REST med HTTP och JSON samt gRPC används för att upprätta kommunikationen. Resultaten visar att upplösningen påverkar runtimebeteendet och den externa kommunikationen blir långsammare. En möjlig slutsats är att påverkan från den externa kommunikationen i förhållande till hur webben beter sig idag är acceptabel. Men om man ska ligga inom teoretiskt optimala gränser kan påverkan ses som för stor.
32
Saha, Sumanta. "OBSAI Interoperability in Multi-Vendor WiMAX Base Station Architecture Environment." Thesis, KTH, Kommunikationssystem, CoS, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91500.
Анотація:
Wireless networks have become a necessity with the increased mobility in human life. From cellular telephony to the Internet, all types of communication are now provided over wireless networks. However, to offer wireless network coverage over an area requires a potentially expensive infrastructure deployment. Such deployment requires base stations which until now have been completely proprietary to the equipment vendors. Moreover, proprietary equipment is almost always costly and offer less flexibility than standardized modular solutions. This situation results in a high cost for network upgradation and hinders network development. A remedy is available via modularization, hence the Open Base Station Architecture Initiative (OBSAI) is trying to modularize and standardize one of the most expensive elements of the wireless infrastructure, the base station. OBSAI standards aim to modularize the base station architecture and enable true interoperability among the various modules. However, the goal has not yet been achieved due to some features of the standard. This thesis project has studied the standards and pointed out some areas that must be concentrated upon when performing interoperability tests. It also proposes several standards amendments to foster greater interoperability among the modules of a base station. This study focuses on the RP3 interface of the OBSAI specification with the goal of making truly inter-operable baseband and RF modules, thus commoditizing the modules. The result is expected to be lower cost, greater interoperability, faster time-to-market, and more cooperative research.Langattomat laajakaistaverkot ovat tulleet välttämättömäksi osaksi liikkuvien ihmisten elämää. Lähes kaikki kommunikaatiotarpeet äänipuheluista internettiin pystytään toteuttamaan langattomien verkkojen avulla. Kuitenkin jotta langattomilla verkoilla pystytään tarjoamaan täysi peittävyys yli maan, se vaatii varsin kalliita investointeja verkkoinfrastruktuuriin. Langattomien verkkojen investoinnit koostuvat suurelta osin tukiasemista, jotka tähän asti ovat olleet kullakin verkkotoimittajalla täysin omanlaisensa toteutus. Kun jokainen verkkotoimittaja toteuttaa kaikki tukiaseman osat erilailla, se tarkoittaa että kutakin tukiaseman osia valmistetaan suhteellisesti pienempiä määriä ja sitä myötä niistä tulee mahdollisesti kalliimpia verrattuna standardoituhin modulaarisiin tukiasemaratkaisuihin. Nykyinen tilanne siis osaltaan johtaa siihen että verkkojen rakentaminen ja päivittäminen on kallista. Eräs ratkaisu tähän ongelmaan on tarjolla modulaarisessa tukiasemaratkaisussa ja siksi OBSAI, Open Base Station Initiative, pyrkii modulaarisoimaan ja standardoimaan yhden kalliimmista verkkoinfrastruktuurin osista, tukiaseman. OBSAI standardi pyrkii modularisoimaan tukiasema-arkkitehtuurin ja mahdollistamaan todellisen yhteensopivuuden tukiaseman eri osien välillä. Tätä todellista yhteensopivuutta ei ole vielä täysin pystytty toteuttamaan, johtuen tietyistä standardin epätarkkuuksista. Tässä lopputyössä on analysoitu OBSAI standardia ja identifioitu alueet, joihin pitää keskittyä, kun modulien välistä yhteensopivuutta testataan. Työn lopputulemana myös ehdotetaan useita parannuksia ja muutoksia standardiin, jotta todellinen yhteensopivuus modulien välillä saavutetaan. Painopiste lopputyössä on OBSAI standardin RP3 rajapinta, joka määrittelee kantataajuusosan (BB) ja radiotaajuusosan (RF) välisen rajapinnan. Kun OBSAI standardia saadaan parannettua työssä ehdotetuin toimenpitein, lopputuloksena on oletettavasti alhaisempi tukiaseman kokonaiskustannus, mahdollisuus käyttää yhteensopivia moduleita eri valmistajilta, nopeampi tuotteiden markkinoille vienti sekä parantunut tutkimusyhteistyö eri yritysten välillä.
Trådlösa nät har blivit en nödvändighet i vår allt mer mobila livsstil. Från mobiltelefoni till Internet, trådlösa nät erbjuder många typer av kommunikation. Men att erbjuda trådlös täckning i ett område kan kräva installation av en mängd dyrbar telekomutrustning. En sådan utbyggnad kräver basstationer som fram till nu har varit patentskyddade av respektive leverantör. Och patentskyddad utrustning är oftast både dyrare och mindre flexibel jämfört med standardiserade modulära lösningar. Resultatet är höga kostnader för att uppgradera näten och att utvecklingen försvåras. Ett botemedel är användningen av standardiserade moduler. Därfär försöker Open Base Station Architecture Initiative (OBSAI) att standardisera moduler i ett av de dyraste nätelementen i trådlösa nät, basstationen. OBSAI har som mål att dela upp basstationen i definierade moduler och möjliggöra fullständig interaktion mellan olika moduler. Men på grund av vissa egenskaper hos standarden har detta inte lyckats. Denna studie har undersökt standarden och pekar på områden som man måste fokusera på när man utför tester mellan moduler. Dessutom föreslås flera tillägg till standarden för att möjliggöra bättre interaktion mellan basstationens moduler. Studien fokuserar på RP3- gränssnittet med målet att möjliggöra standardiserad interaktion mellan basbands- och radio-moduler, så att dessa moduler kan kommerisialiseras. Det förväntade resultatet är lägre kostnader, bättre interaktion mellan moduler, snabbare marknadsintroduktion och mer samarbete inom forskning och utveckling.
33
Amghar, Youssef. "Base d'objets documentaires." Lyon, INSA, 1989. http://www.theses.fr/1989ISAL0070.
Анотація:
Les Modèles Orientés Objets (MOO) ont permis d'aborder autrement les problèmes de conception et d'analyse des applications telles que la documentation. Dans ces modèles, l'objet est le concept unique représentant une "entité" du monde réel. Dans le domaine de la documentation on parle souvent d'objet complexe multi media. Il est muni de connaissances et d'un comportement appelés souvent "propriétés" (attributs et méthodes). Les objets ayant en commun plusieurs propriétés forment une classe d'objets. Tout objet réel possédant ces propriétés est une instance de classe. Le MOO développé dans cette thèse permet grâce à l'introduction d'un nouveau concept "le Méta-G-Objet", de modéliserune collection non finie de modèles de documents codés selon la norme ODA. Le Méta-G-Objet est vu comme l'unification du concept de classe et du concept de méta-classe de Smalltalk considérés chacun comme insuffisant et mal adapté au domaine de la documentation. Le partage d'objets induit dans le graphe des modèles est formalisé. La manipulation des objets documentaires s'est faite à l'aide de Smalltalk dont les principes permettent l'implantation du modèle sans grande difficulté. L'absence de gestion des objets persistants dans Smalltalk, a conduit à l'élaboration d'un modèle de stockage. Trois bases ont été nécessaires : la base des attributs d'objets, la base des méthodes et la base des contenus. L'architecture retenue, à savoir un serveur de documents et des postes de travail pour chaque image Smalltalk a nécessité l'étude de la gestion des accès concurrents.
34
Frisell, Marcus. "Information visualization of microservice architecture relations and system monitoring : A case study on the microservices of a digital rights management company - an observability perspective." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233463.
Анотація:
90% of the data that exists today has been created over the last two years only. Part of the data space is created and collected by machines, sending logs of internal measurements to be analyzed and used to evaluate service incidents. However, efficiently comprehending datasets requires more than just access to data, as Richard Hamming puts it; "The purpose of computing is insight, not numbers." A tool to simplify apprehension of complex datasets is information visualization, which works by transforming layers of information into a visual medium, enabling the human perception to quickly extract valuable information and recognise patterns. This was an experimental design-oriented research study, set out to explore if an information visualization of microservice architecture relations combined with system health data could help developers at a Swedish digital rights management company (DRMC) to find root cause incidents, increase observability and decision support, i.e. simplifying the incident handling process. To explore this, a prototype was developed and user tests consisting of a set of tasks as well as a semi-structured interview was executed by ten developers at DRMC. The results concluded that the proposed solution provided a welcomed overview of service health and dependencies but that it lacked the ability to effectively focus on certain services, essentially making it difficult to find root causes. Visualizations like this seems to be best suited for overview-, rather than focused, comprehension. Further research could be conducted on how to efficiently render large complex datasets while maintaining focus and how to account for external factors.90% av alla data som finns idag har skapats under de senaste två åren. En del av datautrymmet skapas och samlas in av maskiner som genererar loggar innehållandes interna systemmätningar för att utvärdera felaktiga tjänster. För att effektivt förstå ett dataset krävs mer än bara tillgång till data, som Rickard Hamming har sagt; “Syftet med datoranvändning är insikt, inte siffror.” Ett verktyg för att förenkla ens uppfattning av komplexa dataset är informationsvisualisering. Det fungerar genom att transformera lager av information till ett visuellt medium, och på så sätt tillåta mänsklig perception att snabbt extrahera värdefull information och utläsa mönster. Det här var en experimentell, design-orienterad, forskningsstudie med syftet att utforska ifall en informationsvisualisering av mikrotjänsters relationer kombinerat med system-hälso-data kunde hjälpa utvecklare på ett svenskt förvaltningsföretag av digitala rättigheter (DRMC) att hitta grundorsaken till felaktiga mikrotjänster samt utöka observerbarhet och beslutstöd, d.v.s. förenkla felhanteringsprocessen. För att utforska detta problem så utvecklades en prototyp som testades genom att låta tio utvecklare på DRMC utföra ett antal olika uppgifter samt svara på en semi-strukturerad intervju. Resultatet visade på att den föreslagna lösningen möjliggjorde en välkommen överblick över systemets hälsa och relationer, men också att den saknade möjligheten att effektivt fokusera på specifika tjänster, vilket ledde till att grundorsaksproblem var svåra att hitta. Visualiseringar som denna verkar fungera bäst för att presentera en överblick av ett system, snarare än ett fokus på specifika tjänster. Framtida forskning skulle kunna utföras för att utreda hur visualiseringar effektivt kan återge komplexa dataset utan att förlora fokus på specifika delar, samt hur externa faktorer kan integreras.
35
Ferraz, de Abreu Pedro Manuel Barbosa. "Intelligent graphic interface : capturing rules of human-computer interaction in a knowledge base." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/66323.
36
Derby, Gregory A. (Gregory Alan) 1966. "Base building capital expenditures in the office sector : historical incidence and implications for forecasting." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/65707.
37
Bertilsson, Erik. "A Scalable Architecture for Massive MIMO Base Stations Using Distributed Processing." Thesis, Linköpings universitet, Datorteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-133998.
Анотація:
Massive MIMO is an emerging technology for future wireless systems that has received much attention from both academia and industry recently. The most prominent feature of Massive MIMO is that the base station is equiped with a large number of antennas. It is therefore important to create scalable architectures to enable simple deployment in different configurations. In this thesis, a distributed architecture for performing the baseband processing in a massive OFDM MU-MIMO system is proposed and analyzed. The proposed architecture is based on connecting several identical nodes in a K-ary tree. It is shown that, depending on the chosen algorithms, all or most computations can be performed in a distrbuted manner. Also, the computational load of each node does not depend on the number of nodes in the tree (except for some timing issues) which implies simple scalability of the system. It is shown that it should be enough that each node contains one or two complex multipliers and a few complex adders running at a couple of hundres MHz to support specifications similar to LTE. Additionally the nodes must communicate with each other over links with data rates in the order of some Gbps. Finally, a VHDL implementation of the system is proposed. The implementation is parameterized such that a system can be generated from a given specification.
38
El, Fallah Seghrouchni Amal. "Architecture d'une base de connaissances pour l'analyse des reseaux de petri." Paris 6, 1991. http://www.theses.fr/1991PA066475.
Анотація:
Cette these presente la conception et la realisation d'une base de connaissances multiformalismes permettant le developpement d'outils de validation des systemes paralleles modelises par des reseaux de petri. Deux aspects sont traites: la realisation d'une base de connaissances dotee d'une architecture particuliere autorisant une implementation aisee du caractere incremental et multiformalisme tout en garantissant une efficacite d'execution appreciable. Cet aspect traite les differents problemes lies aux architectures distribuees et a la representation de la connaissance et l'elaboration d'une base de connaissances modulaire avec le niveau de controle approprie pour la gestion de cette modularite. L'introduction de la notion de tableau noir a ete d'un grand apport; l'etablissement d'un controle hierarchise approprie. Cet aspect, quant a lui, propose un controle de resolution hierarchise base sur le metafiltrage des paquets de connaissances au moyen de metaconnaissances. L'introduction des operations de transformation des representations permettent d'heriter automatiquement les proprietes d'une classe sur une autre (classe au sens du formalisme des reseaux de petri). La resolution de problemes complexes inherents a la theorie des reseaux de petri, repose sur le principe decomposition en sous-problemes proche des decompositions et/ou avec une notion de satisfaction dirigee par les buts et les paquets de connaissances. Nous avons mis en place des strategies d'evaluation avec des notions de recherche d'echec au plus tot pour les buts de type butsvs (but a sequence de validation statique ou sequentielle) et de succes au plus tot pour les buts de type butsvd (but a sequence de validation dynamique). Le monde auquel nous nous sommes interesses est decrit sous forme de classes de connaissances hierarchisees ouvrant la voix a une architecture qui synthetiserait les avantages de la representation orientee objet et ceux d'une architecture de tableau noir en faisant apparaitre des methodes particulieres qui permettront de profiter des concepts d'heritage et de polymorphisme, et de ce fait, reduire la redondance d'information
39
Sabri, Nawel. "Une architecture à base de composants CORBA pour des services personnalisés." Evry-Val d'Essonne, 2003. http://www.theses.fr/2003EVRY0024.
40
Barais, Olivier. "Construire et maîtriser l'évolution d'une architecture logicielle à base de composants." Lille 1, 2005. https://ori-nuxeo.univ-lille1.fr/nuxeo/site/esupversions/1495c084-3273-41d6-aea6-c5343a3d2120.
Анотація:
Dans une industrie du logiciel où la complexité des applications ne cesse de croître, un des objectifs du génie logiciel est de conserver l'intelligibilité du processus de construction et de maintenance de ces applications. Dans ce cadre, le concept de composant a été introduit comme une extension du concept d'objet pour faciliter la conception d'applications réparties complexes, c'est-à-dire formées de nombreux éléments en coopération, distribuées sur différents sites d'exploitation, et de nombreuses contraintes qui expriment des exigences variées (persistance, sécurité, tolérance aux pannes, etc. ). Il existe à ce jour de nombreux modèles de composants avec des objectifs différents. Cependant, un des points communs de ces modèles est la mise en lumière de l'architecture de l'application, c'est-à-dire une description de haut niveau de cette application décomposée en différents composants interconnectés et définis par leurs fonctionnalités requises et offertes. De par la complexité de certaines applications, la définition de l'architecture est elle-même une opération délicate et très propice aux erreurs. L'objectif de cette thèse vise à améliorer la maîtrise de la complexité de la construction de l'architecture d'une application définie par assemblage de composants. Nous proposons pour cela un modèle de composant abstrait, nommé SafArchie, qui permet d'assister l'architecte dans la construction d'une architecture logicielle cohérente. Ainsi, dans SafArchie, l'interface des différents composants d'une architecture est spécifiée à l'aide de contrats. Ces contrats permettent de définir la structure du composant, mais aussi son comportement vis-à-vis de son environnement. A partir de ces différentes informations et de la définition de l'assemblage de composants, nous proposons une notion de compatibilité entre composants interconnectés. Cette compatibilité permet de déterminer la cohérence de l'architectureUn deuxième axe de la thèse part du constat qu'il est difficile de construire un assemblage de composants qui adresse l'ensemble des préoccupations d'une application en une seule étape. L'idéal est alors de proposer une démarche de construction incrémentale où l'architecte peut à chaque étape ajouter une nouvelle préoccupation à son architecture. Malheureusement, les modèles de composants ne proposent en générale qu'une unique dimension de structuration d'une application, SafArchie n'échappe pas à cette règle. Dès lors, certaines préoccupations comme la sécurité, la persistance ou la traçabilité ne peuvent être correctement structurées au sein d'un seul composant et se retrouvent alors noyées au sein de nombreux éléments de l'architecture. Cette mauvaise structuration est très préjudiciable pour l'intégration de ces préoccupations dans une architecture existante. Nous proposons donc, dans une deuxième partie de cette thèse, un canevas de conception d'architecture nommé TranSAT qui permet l'intégration de nouvelles préoccupations dans une architecture par transformation de cette dernière. Ce canevas introduit la notion de patron d'architecture pour structurer les différentes préoccupations transverses d'une application. Ce patron comprend les éléments d'architecture à intégrer, les transformations à apporter sur l'architecture de base, mais aussi un ensemble de contraintes génériques sur les éléments d'une architecture cible sur laquelle le patron peut être intégré. De plus, TranSAT propose un langage dédié pour spécifier les modifications à apporter sur l'architecture de base afin d'intégrer la nouvelle préoccupation. Ce langage est concis et expressif, sa spécialisation permet de produire différentes analyses statiques afin de garantir la cohérence de l'architecture résultante sans analyser la totalité de cette architecture
41
Ferreira, Koyama Mauro Vernadat François. "Architecture de pilotage d'atelier de production à base de composants génériques." [S.l.] : [s.n.], 2001. ftp://ftp.scd.univ-metz.fr/pub/Theses/2001/Ferreira_Koyama.Mauro.SMZ0104.pdf.
42
Chaillot, Mathias. "Une architecture de contrôle réactif pour la résolution coopérative de problèmes." Grenoble INPG, 1993. http://www.theses.fr/1993INPG0111.
Анотація:
Un environnement de résolution de problèmes est un système à base de connaissances qui pilote des modules algorithmiques. Nous étudions le problème de la réactivité dans ce type de systèmes et proposons une architecture appelée TRAM. Dans TRAM, l'état courant de la résolution est modélisé dans une base d'objets dont les mises à jour sont effectuées par ces modules algorithmiques. Le modèle objet propose détecte les événements pris en compte et identifie les situations qui permettent d'activer les modules algorithmiques. On montre ainsi l'intérêt de la classification d'instances pour caractériser l'état d'un système réactif. Le contrôle est organise en deux niveaux : la réactivité est gérée par un superviseur qui est défini a partir d'un automate d'états finis et qu'identifie la tache a réaliser, la planification est assurée par un gestionnaire de taches. L'étude de la sélection dynamique de méthodes dans ce modèle de taches aboutit à plusieurs algorithmes qui prennent en compte l'activité et l'utilité des méthodes, la rationalité du processus de délibération et la gestion des possibilités d'activation. TRAM est réalisé selon une approche client-serveur et expérimenté dans les applications de calcul scientifique.
43
Montelius, Anna. "An Exploratory Study of Micro Frontends." Thesis, Linköpings universitet, Programvara och system, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-176963.
Анотація:
"Microservices" has become a real buzz word in the software development community during the last couple of years. Most developers are familiar with the architectural concept which solves the problem of systems growing to large monoliths too complex to handle. This architecture has however mostly been used in backend development, even though many companies are struggling with large, monolithic frontend codebases. This is where micro frontends come in, an architectural as well as organisational approach to developing applications all the way from presentation to data layer. The micro frontends approach is relatively new, and even though there is some talk about it in the software community, many companies are unfamiliar with it, and there is very limited scientific work performed on the topic. The aim of this study was to investigate strengths of and challenges with micro frontends, and specifically how the modifiability of a web application is affected by developing it as a micro frontends project. The method for fulfilling the aim consisted of several parts. During one part, two frontend prototypes of a web application were implemented, one using a Single Page Application technique and one using a micro frontends technique. Another part consisted of interviewing practitioners in the software field with relevant backgrounds to gain their perspective on micro frontends. The results were also used to evaluate which prototype would be most suitable for the specific web application. During the last part of the method, measurements on the implemented prototypes were performed to be used to estimate the modifiability of the prototypes using a mathematical model of modifiability called SQMMA. Based on the results, this report provides an extensive summary of strengths of micro frontends, among other things that there are both beneficial and disadvantageous aspects of micro frontends when it comes to modifiability, risks that should be considered when adopting micro frontends, and a discussion on when to use it and not.
44
Prochazka, Marek. "La transactions avancées dans les architectures logicielles à base de composants." Evry-Val d'Essonne, 2002. http://www.theses.fr/2002EVRY0002.
Анотація:
Le sujet de la thèse est le traitement de transactions dans les architectures logicielles à base de composants, dans lesquelles chaque composant est déployé dans un conteneur et où les requêtes des clients peuvent être traitées dans le cadre d’une transaction interposée par le conteneur. Puisque pour chaque requête un objet délégataire du conteneur est interposé, un objet délégataire est capable de modifier, selon la politique de propagation de transaction spécifiée avec l’interface métier du composant, le contexte de la transaction dans laquelle la méthode invoquée sur le composant sera exécutée. Un nouveau modèle de transactions, appelé « Transactions Bourgogne » est introduit pour répondre aux questions posées par le caractère spécifique des architectures logicielles à base de composants. En plus des événements significatifs de base (begin, commit et abort), les Transactions Bourgogne supportent des événements significatifs avancés correspondant à des primitives transactionnelles avancées, qui permettent d’établir des dépendances de contrôle de flot entre transactions, de donner des permissions depuis une transaction à une autre et de déléguer des composants d’une transaction à une autre. Par contraste avec les architectures logicielles classiques à base de composants, qui spécifient la politique de propagation des transactions tardivement (via le descripteur de déploiement), nous proposons de spécifier la politique de propagation des transactions en tant que partie de l’interface du composant, au moyen de l’approche « attribut NT&CT ». Le comportement transactionnel d’un composant est spécifié pour les deux cas où aucune transaction n’est présente dans la requête cliente (NT), et où la requête est générée dans le contexte d’une transaction cliente (CT). Pour prendre en compte les modèles de transactions avancées dans la spécification de la politique de propagation, les primitives avancées des Transactions Bourgogne sont appliquées à des objets délégataires afin de permettre aux transactions interposées par le conteneur de coopérer conformément au modèle de transaction désiré. Nous proposons par ailleurs une technique de propagation de transactions et de verrouillage pour des architectures logicielles généralisées à base de composants, dans lesquelles un composant peut avoir plusieurs interfaces de type « fournit » et « requiert » et être inclus dans un autre composant. Dans les Transactions Bourgogne, chaque composant est divisé en unités transactionnelles qui correspondent aux parties indépendantes de l’état persistant du composant et chaque interface « fournit - requiert » des composants est associée à une unité transactionnelle. La politique de propagation des transactions est spécifiée dans chaque interface « fournit » de composant, afin de définir le comportement transactionnel que ce composant assure à d’autres composants liés à lui via l’interface « fournit » et aussi dans chaque interface « requiert » de composant, afin de définir le comportement transactionnel des composants liés à lui via l’interface « requiert ». Des critères de compatibilité d’interfaces associées par liaison, spécialisation ou délégation, sont également définisThe thesis focuses on transaction processing in component-based software architectures, where every conponent is deployed into a container and client requests may be performed in the scope of a container-interposed transaction. Since every client request is interposed by the container’s delegator objects, a delegator object is able to modify the transaction context in which the requested component method will be executed according to the transaction propagation policy specified along with the component business interface. To address issues determined by the character of component-based software architectures, a novel transaction model called Bourgogne Transactions is introduced. Beside the basic significant events (i. E. , begin, commit and abort) Bourgogne Transactions support advanced significant events corresponding to advanced transaction primitives, which allow to establish flow control dependencies among transactions, give permissions from a transaction to another transaction, and delegate components from a transaction to another transaction. Opposed to current component-based software architectures, which specify the transaction propagation policy as late as in the deployment descriptor, we propose to specify the transaction propagation policy as a part of the component interface by means of the NT&CT attribute approach. The transaction behavior of a component is specified for the case where a client transaction is not present in a client request (NT) and for the case where a request is issued in the scope of client transaction (CT). To employ advanced transaction models in the transaction propagation policy specification, the Bourgogne Transaction advanced transaction primitives are applied in delegator objects in order to let container-interposed transactions cooperate in compliance with a desired transaction model. A technique for the transaction propagation and locking is also proposed for generalized component-based software architectures, where a omponent may have multiple provides - and requires- interfaces and may be nested in another component. In Bourgogne Transactions, each component is divided into transactional units, which reflect independent parts of the component persistent state and every component’s provides-interface is associated with a particular transactional unit. The transaction propagation policy is specified on each components’s provides-interface, to declare what transactional behavior the component supports to components that would be tied via the provides-interface and also on each composent’s requires interface, to declare what transactional behavior of components that would be tied via the requires-interface the component requires. Criteria for compatibility of interfaces that would be tied via binding, subsumption or delegation are also defined
45
Dejnozkova, Eva. "Architecture dédiée au traitement d'image base sur les équations aux dérivées partielles." Phd thesis, École Nationale Supérieure des Mines de Paris, 2004. http://pastel.archives-ouvertes.fr/pastel-00001180.
Анотація:
Les méthodes de traitement d'images fondées sur les équations aux dérivées partielles (EDP) bénéficient d'une attention particulière de la part de la communauté scientifique. Le nombre d'applications a considérablement augmenté après la formulation du problème sous forme d'ensembles de niveaux. Les EDPs s'appliquent dans de nombreux domaines tels le filtrage des images (diffusion non-linéaire), les contours actifs utilisés pour la segmentation des images statiques (graphe de Voronoï, Ligne de Partage des Eaux, plus court chemin, détection d'objets), aussi bien que des séquences d'images (suivi d'objets) ou encore des méthodes plus récentes tel le shape-from-shading. Les applications industrielles de ces méthodes sont néanmoins très limitées, d'une part par une complexité considérable de calculs (nombre d'itérations très élevé, par ex.), d'autre part par des difficultés rencontrées lors d'implantation embarquées (consommation d'énergie, exigences mémoire). Quelques expériences temps-réel ont été publiées avec des super-calculateurs ou des accélérateurs graphiques. Quant aux applications embarquées, elles sont à notre connaissance quasi-inexistantes. Notre but est de proposer une architecture dédiée, facilitant tant l'implantation temps-réel qu'embarquée. En vue de cet objectif nous proposons un nouvel algorithme de solution de l'équation Eikonale/calcul de fonction distance qui procède en parallèle, élimine l'usage des files d'attente hiérarchiques et permet d'obtenir la solution sur la totalité ou seulement sur une partie de l'image (le narrow band). La complexité de cet algorithme, nommé Massive Marching, est linéaire. Nous estimons que l'impact de Massive Marching est d'autant plus important pour la communauté de Morphologie Mathématique, qu'il s'agit du premier algorithme permettant d'obtenir en parallèle la ligne de partage des eaux non-biaisée. Ensuite, nous proposons deux types d'architecture (i) SIMD et (ii) plusieurs coeurs de processeurs embarqués implantant Massive Marching en parallèle ou semi-parallèle. Ces mêmes types d'architecture peuvent être utilisés pour implanter un filtrage aussi bien que des méthodes à évolution d'interface. La même architecture peut donc être utilisée pour implanter une application complète, composée de différents types d'algorithmes comme par exemple filtrage suivi par segmentation.
46
Guan, Tut San. "Programming model for a computer architecture base on free-space optical communications." Thesis, Queen Mary, University of London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244690.
47
Megahed, Mohamed Helmy Mostafa. "SurvSec Security Architecture for Reliable Surveillance WSN Recovery from Base Station Failure." Thèse, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31154.
Анотація:
Surveillance wireless sensor networks (WSNs) are highly vulnerable to the failure of the base station (BS) because attackers can easily render the network useless for relatively long periods of time by only destroying the BS. The time and effort needed to destroy the BS is much less than that needed to destroy the numerous sensing nodes.
Previous works have tackled BS failure by deploying a mobile BS or by using multiple BSs, which requires extra cost. Moreover, despite using the best electronic countermeasures, intrusion tolerance systems and anti-traffic analysis strategies to protect the BSs, an adversary can still destroy them. The new BS cannot trust the deployed sensor nodes. Also, previous works lack both the procedures to ensure network reliability and security during BS failure such as storing then sending reports concerning security threats against nodes to the new BS and the procedures to verify the trustworthiness of the deployed sensing nodes. Otherwise, a new WSN must be re-deployed which involves a high cost and requires time for the deployment and setup of the new WSN. In this thesis, we address the problem of reliable recovery from a BS failure by proposing a new security architecture called Surveillance Security (SurvSec).
SurvSec continuously monitors the network for security threats and stores data related to node security, detects and authenticates the new BS, and recovers the stored data at the new BS. SurvSec includes encryption for security-related information using an efficient dynamic secret sharing algorithm, where previous work has high computations for dynamic secret sharing. SurvSec includes compromised nodes detection protocol against collaborative work of attackers working at the same time where previous works have been inefficient against collaborative work of attackers working at the same time.
SurvSec includes a key management scheme for homogenous WSN, where previous works assume heterogeneous WSN using High-end Sensor Nodes (HSN) which are the best target for the attackers. SurvSec includes efficient encryption architecture against quantum computers with a low time delay for encryption and decryption, where previous works have had high time delay to encrypt and decrypt large data size, where AES-256 has 14 rounds and high delay. SurvSec consists of five components, which are:
1. A Hierarchical Data Storage and Data Recovery System.
2. Security for the Stored Data using a new dynamic secret sharing algorithm.
3. A Compromised-Nodes Detection Algorithm at the first stage.
4. A Hybrid and Dynamic Key Management scheme for homogenous network.
5. Powerful Encryption Architecture for post-quantum computers with low time delay.
In this thesis, we introduce six new contributions which are the followings:
1. The development of the new security architecture called Surveillance Security (SurvSec) based on distributed Security Managers (SMs) to enable distributed network security and distributed secure storage.
2. The design of a new dynamic secret sharing algorithm to secure the stored data by using distributed users tables.
3. A new algorithm to detect compromised nodes at the first stage, when a group of attackers capture many legitimate nodes after the base station destruction. This algorithm is designed to be resistant against a group of attackers working at the same time to compromise many legitimate nodes during the base station failure.
4. A hybrid and dynamic key management scheme for homogenous network which is called certificates shared verification key management.
5. A new encryption architecture which is called the spread spectrum encryption architecture SSEA to resist quantum-computers attacks.
6. Hardware implementation of reliable network recovery from BS failure.
The description of the new security architecture SurvSec components is done followed by a simulation and analytical study of the proposed solutions to show its performance.
48
Alauzet, Aline. "Adele : une architecture à base de tableau noir pour la simulation ergonomique." Nancy 1, 1998. http://docnum.univ-lorraine.fr/public/SCD_T_1998_0026_ALAUZET.pdf.
Анотація:
L'évaluation ergonomique de maquettes de produits (habitacles de voitures, poids-lourds,) réalisées sous logiciel de CAO nécessite des outils de simulation permettant de tester l'adéquation du produit pour ses futurs utilisateurs. Les mannequins graphiques 3d sont les outils de simulation utilisés pour effectuer des tests d'encombrement, d'atteinte ou de vision. Bien que ces outils remplissent bien leur fonction d'aide, leur manipulation nécessite une véritable expertise. L'utilisateur (concepteur de bureau d'étude) doit aussi posséder l'expertise lui permettant de décider, au vu de la position obtenue avec le mannequin, si l'implantation choisie pour les constituants du produit est bonne. Sur la base de l'analyse des outils d'aide à la simulation ergonomique existants, nous proposons une nouvelle approche permettant de remédier à ces défauts en automatisant la manipulation du mannequin et en fournissant des aides à l'évaluation ergonomique. Cette approche est basée sur la constitution d'un modèle de l'activité motrice et l'élaboration de bases de connaissances sur les stratégies de mouvement et sur le diagnostic ergonomique. Le modèle d'activité, conçu a l'aide d'une modélisation objet, constitue un outil de spécification des taches que le mannequin doit effectuer. L'architecture conçue, basée sur un modèle de tableau noir, nous permet la modélisation des aspects de contrôle liés au pilotage du mannequin graphique et à la production d'un diagnostic ergonomique. Le prototype du système, nomme adele, associe trois éléments : le modèle graphique d'operateur humain man3d (développé à l'inrets/lesco), une base de données objet (développée avec le sgbd gemstone) et un système à base de tableau noir (développé avec l'outil atome, du LORIA a Nancy). La liaison entre atome et le sgbd utilisé a fait l'objet d'un développement particulier, permettant l'implantation du tableau noir dans la base de données objetThe ergonomic evaluation of computer assisted design prototypes of systems like cars or trucks requires simulation tools, in order to assess the convenience of the product for its future users. 3D graphic mannequins are such simulation tools, which provides facilities for fit, vision and reach tests. These tools prove to be very useful, however the use of the tools is in fact not easy at all due to the large amount of expertise needed to manipulate them. Furthermore, the user must possess a great amount of expert knowledge to decide, on the basis of the mannequin posture, whether he has chosen a good implantation for the elements of the product, or not. We analyse the existing ergonomie simulation tools, then we propose a new approach, based on the automation of the mannequin handling and the add of ergonomic assessment tools. We propose a motor activity model (which provides a tool for the specification of the tasks to be simulated by the mannequin) and knowledge bases (for movement strategies and ergonomie diagnosis). The system is based on a blackboard architecture which helps to model the control aspects (mannequin handling and production of an ergonomic diagnosis). The prototype of our system, ADELE, has three components: a graphical human model, MAN3D (developed at INRETS/LESCO), an object database (developed with GemStone DBMS) and a blackboard system (developed with Atome, a LORIA-Nancy tool). A specific link between Atome and GemStone has been developed, which allows to implement a blackboard located in the object database
49
Saleh, Hayder. "Une architecture novatrice de sécurité à base de carte à puce Internet." Versailles-St Quentin en Yvelines, 2002. http://www.theses.fr/2002VERSA009.
Анотація:
Le protocole Smart TP, introduit dans ce mémoire, propose une nouvelle architecture de communication d'une carte à puce Internet permettant à la carte d'agir comme un vrai noeud d'Internet. Ainsi, cette carte pourra participer aux protocoles d'Internet les plus répandus de manière plus active et indépendamment du terminal hôte. La sécurité sur Internet est une des préoccupations majeures de notre société, mettant en action différents aspects, notamment économiques et technologiques. Le déploiement de la carte à puce en tant que dispositif hautement protégé au service des protocoles de sécutité sur Internet constitue le coeur du sujet de cette thèse. Les défis technologiques révélés par ce déploiement ont été étudiés et évalués à travers cette recherche. Une implémentation du protocole proposé a été réalisée pour loger un serveur WEB conforme aux normes Internet dans une carte à puce Java. Ceci a permis d'étudier les problèmes de performance et de faisabilité, ainsi que de découvrir les possibilités d'amélioration de ce protocole (SmartTP). Une démonstration à grande échelle a été ensuite conduite pour explorer les débouchés industriels de cette technologie. Une analyse approfondie a été faite sur l'implication d'une carte à puce dans le protocole SSL. Ce dernier, est pris comme un exemple pour extrapoler les points forts et les points faibles de la carte dans un environnement Internet. Les problèmes issus de l'exemple SSL et les recommandations apportées sont largement valables pour les autres protocoles et constituent les fruits de cette recherche.
50
NGUYEN, ROBERT. "Architecture generique de systeme de vision a base de retine artificielle programmable." Paris 11, 2000. http://www.theses.fr/2000PA112238.
Анотація:
En vingt ans, les retines artificielles ont acquis une maturite leur permettant de s'affirmer parmi les systemes de vision. Mais jusque la les aspects phototransduction et traitement ont eclipse la question du controle. L'objectif est ici de savoir comment organiser le controle d'un systeme de vision a base de retine artificielle pour qu'il soit efficace, idealement en degageant une architecture materielle/logicielle generique. Cette genericite se concoit pour un groupe restreint de l'ensemble heterogene des retines : les retines numeriques programmables depourvues de structures de controle. La retine dite tcl est utilisee comme support d'experimentation, notamment au sein de 3 architectures de machine implantees sur le banc de prototypage reprogrammable nomme emfri et sur deux plates-formes mobiles. La premiere architecture materielle, emulee par emfri, melange dans un processeur specifique les traitements scalaires et retiniens pour une bonne compacite mais aux depens de l'efficacite. Les deux autres architectures implantent une structure biprocesseur associant un microprocesseur courant et un processeur retinotopique specifique. Ce dernier est en charge du sequencement des instructions et de la gestion des informations retiniennes. Les aspects logiciels sont declines suivant 3 niveaux de complexite : langage retine, strategie de communication symetrique, et langage parallele de haut niveau du biprocesseur. Finalement, les performances et les limitations des aspects materiels et logiciels amenent a reconsiderer le reseau de communication tcl et le nombre de registres par pe. Cette analyse permet aussi de definir des criteres de selection architecturale en fonction des besoins d'une application. La structure biprocesseur