Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

The emergence of new architectures like the cloud open new challenges for data management. It is no longer pertinent to reason with respect a to set of computing, storage and memory resources, instead it is necessary to conceive algorithms and processes considering an unlimited set of resources usable via a "pay as U go model", energy consumption or services reputation and provenance models. Instead of designing processes and algorithms considering as threshold the resources availability, the cloud imposes to take into consideration the economic cost of the processes vs. resources use, results presentation through access subscription, and the parallel exploitation of available resources. Our research contributes to the construction of service based data management systems. The objective is to design data management services guided by SLA contracts. We proposed methodologies, algorithms and tools for querying, deploying and executing service coordinations for programming data management functions. These functions, must respect QoS properties (security, reliability, fault tolerance, dynamic evolution and adaptability) and behaviour properties (e.g., transactional execution) adapted to application requirements. Our work proposes models and mechanisms for adding these properties to new service based data management functions.

Nos tempos atuais, cada vez mais as organizações têm investido em equipamentos e infra-estrutura de educação a distância (EAD). Grande parte dos estudos até hoje realizados dizem respeito a aspectos pedagógicos relacionados a esse tipo de sistema produtivo. Contudo, há poucos estudos dedicados a sua gestão. Esta dissertação busca, por meio de uma pesquisa à literatura pertinente, seguida de uma pesquisa de campo, sistematizar o conhecimento sobre a gestão de um sistema de operações de EAD, buscando formas para otimizar sua disponibilidade operacional. Ao longo do trabalho, a disponibilidade é tratada com um indicador de resultado de duas diferentes funções da organização: função gestão de contratos e função manutenção. A primeira diz respeito ao acordo de nível de serviço (SLA) firmado entre a organização foco deste estudo e um fornecedor de serviços de telecomunicações. A segunda função compreende a forma como são adotadas abordagens ou políticas de manutenção para os equipamentos utilizados para a execução desse tipo de serviço. Assim, descreve-se o contexto em que se inserem a disponibilidade e as duas funções a ela relacionadas e buscam-se formas para coordenar essas funções com o objetivo de otimizar a disponibilidade operacional do sistema produtivo. Algumas proposições foram estruturadas e verificadas numa organização, através da metodologia científica pesquisa-ação. Um instrumento referencial foi elaborado para amparar a pesquisa de campo visando facilitar a verificação das proposições propostas, além de colaborar para melhor atingir os objetivos propostos. A conclusão da pesquisa revela que as proposições de estudo não se confirmaram de forma plena, apontando para um sensível distanciamento entre teoria e pratica organizacional, deixando, assim, espaço aberto para novos estudos. / In present days, organizations are investing increasingly in equipment and infrastructure for distance education (DE). Great part of the studies carried out until today focus on the pedagogical aspects related to this type of productive system. However, there are few studies dedicated to its management. It is the goal of this study, through research in specific literature followed by a field research, to systemize the knowledge on management of an operational system for DE, searching for ways to optimize its operational availability. Throughout the work, the availability is considered a result indicator for two different functions of the organization: contract management function and maintenance function. The former one says respect to the service level agreement (SLA) firmed between the organization, focus of this study, and a supplier of telecommunications services. The latter is concerned with the ways that maintenance approaches and politics for the equipment involved in the execution of this type of service are adopted. Thus, the context in which the availability and both related functions are enclosed has been described and ways to co-ordinate these functions with the goal of optimizing the productive system operational availability is searched. The framework of some proposals was developed and verified in an organization through the scientific methodology ?Action Research?. A reference instrument was elaborated to support the field research aiming to ease the verification of the proposals that have been made, besides helping to achieve the proposed goal. The research conclusion discloses that the study proposals weren?t fully confirmed, leading to a considerable withdraw between organizational theory and practice, leaving, thus, an open space for new studies.

The objective of this thesis is to propose and describe the database, which enables to measure compliance of Service Level Agreement suppliers of software applications that work with HP Quality Center. The work describes specific solution used in project to implement a new core business system, describes requirements for functionality and use of result the solution. Briefly described is also HP Quality Center, the testing tool, from which are taken the input data and what possibility offers for monitoring the SLA. The proposed database allows calculation of the time which is actually spent by suppliers on solving the errors and comparison of calculated time with the defined SLA. It will also describe how to import data into the database and the basic reports, which are usable after implementation of the proposed solution.

L’objectif de la thèse est d’étudier la gestion de bout en bout des architectures à la SDN, et comment nos briques OSS (Operation Support System) doivent évoluer: cela implique d’étudier les processus métier associés, leurs implémentations ainsi que l’outillage nécessaire. Les objectifs de la thèse sont donc de répondre aux verrous suivants:1. Identifier les changements impliqués par l’émergence de ces réseaux programmables sur les architectures de gestions en termes d’exigences ou "requirements". L’étude peut être focalisée sur un type de réseau, mobile par exemple. 2. Identifier l’évolution à apporter aux interfaces de gestions actuelles: quelles alternatives aux FCAPS (fault, configuration, accounting, performance, and security) ? Quels changements à apporter aux couches de gestions allant du gestionnaire d’équipement ou "Element Management System" jusqu’au OSS ? / The main goal of the PhD activities is to define and develop architecture and mechanisms to ensure consistency and continuity of the operations and behaviors in mixed physical/virtual environments, characterized by a high level of dynamicity, elasticity and heterogeneity by applying a cognitive approach to the architecture where applicable. The target is then to avoid the "build it first, manage it later" paradigm. The research questions targeted by the PhD are the following: 1. Identify the changes on Network Operation Support Systems implementation when using SDN as a design approach for future networks. The study could be restricted to mobile networks for example, or sub-part of it (CORE networks, RAN, data centers, etc); 2.Identify the needed evolution at the management interfaces level: a. Shall we need alternative to the well-known FCAPS and do we still need the element management system? b. What will change to provision an SDN based service? c. How to ensure resiliency of SDN based networks?

Cloud computing is perceived as the technological innovation that will transform future investments in information technology. As cloud services become more ubiquitous, public and private enterprises still grapple with concerns about cloud computing. One such concern is about service level agreements (SLAs) and their appropriateness. While the benefits of using cloud services are well defined, the debate about the challenges that may inhibit the seamless adoption of these services still continues. SLAs are seen as an instrument to help foster adoption. However, cloud computing SLAs are alleged to be ineffective, meaningless, and costly to administer. This could impact widespread acceptance of cloud computing. This research was based on the transaction cost economics theory with focus on uncertainty, asset specificity and transaction cost. SLA uncertainty and SLA asset specificity were introduced by this research and used to determine the technical and non-technical attributes for cloud computing SLAs. A conceptual model, built on the concept of transaction cost economics, was used to highlight the theoretical framework for this research. This study applied a mixed methods sequential exploratory research design to determine SLA attributes that influence the adoption of cloud computing. The research was conducted using two phases. First, interviews with 10 cloud computing experts were done to identify and confirm key SLA attributes. These attributes were then used as the main thematic areas for this study. In the second phase, the output from phase one was used as the input to the development of an instrument which was administered to 97 businesses to determine their perspectives on the cloud computing SLA attributes identified in the first phase. Partial least squares structural equation modelling was used to test for statistical significance of the hypotheses and to validate the theoretical basis of this study. Qualitative and quantitative analyses were done on the data to establish a set of attributes considered SLA imperatives for cloud computing adoption.

Molntjänster spelar en betydande roll i dagens samhälle och används i såväl den privata sektorn som den offentliga. I och med den utbredda användningen har det ur ett organisationsperspektiv uppstått ett behov att utvärdera tjänsterna. Denna undersökning behandlar hur företags val av molntjänster går till i praktiken, vilka krav företag ställer på molntjänster, vilka krav företag anser vara viktigast, samt hur väl molntjänster lyckas bemöta dessa krav. Undersökningen utfördes genom intervjuer och en kvalitativ analys av tre företags situationer gällande molntjänster. Sammanfattningsvis dras slutsatsen att företagens val av molntjänstleverantör beror på en kombination av lock-ins och tidigare uppfattning av leverantören. Det visade sig att krav på säkerhet och foglighet var viktigast för alla tre företag, och att alla tre även rangordnat pålitlighet och tillförlitlighet som näst viktigast. Därefter skiljer sig rangordningen av kraven något mellan företagen, vilket bland annat beror på att deras kunder har olika krav på diverse faktorer. Vad gäller bemötandet av kraven från leverantören visade det sig att alla tre företag generellt upplever en stor nöjdhet för samtliga krav.

O paradigma de computação em nuvem, por meio de seus modelos de serviço e implantação, apresenta para os provedores de serviço e consumidores benefícios e desafios. Um dos principais desafios apontados pela área de computação em nuvem é com relação à segurança da informação, especificamente a questão de conformidade com relação a contratos firmados entre o provedor e o consumidor. O acordo de nível de serviço (SLA) é um destes contratos, no qual são estabelecidos requisitos para a entrega e operação do serviço contratado pelo consumidor, bem como penalidades em caso de não atendimento a requisitos estabelecidos no contrato. Comumente, em um SLA definido entre provedor de serviço e consumidor as necessidades de disponibilidade e desempenho com relação ao serviço contratado são especificados, o que não ocorre com relação às necessidades de segurança. A necessidade de especificação de requisitos de segurança em um SLA, em especial confidencialidade e integridade, para o contexto de computação em nuvem, bem como arquiteturas de computação que tratem de requisitos de segurança em um SLA e efetuem o gerenciamento destes requisitos durante o ciclo de vida do SLA, encontram-se em evolução, se comparado aos requisitos de disponibilidade. Considerando a demanda crescente de incorporação de SLA de Segurança nos contratos de serviços de computação em nuvem, este trabalho tem como objetivo propor e avaliar um arcabouço de gerenciamento de serviços de computação em nuvem para o modelo de infraestrutura como serviço (IaaS), tendo como base requisitos de segurança especificados em um SLA, em especial os requisitos de confidencialidade e integridade. O gerenciamento proposto pelo arcabouço contempla as etapas do ciclo de vida de um SLA, que compreende as fases de: i) definir e especificar o SLA; ii) gerenciar e implantar o SLA; iii) executar e gerenciar o SLA e iv) finalizar o SLA. A validação do arcabouço proposto é realizada por meio da sua aplicação em um cenário de uso, onde será verificado o atendimento aos requisitos de segurança definidos e especificados no SLA. Para assegurar que o arcabouço proposto é seguro, bem como a sua integração com o ambiente de computação em nuvem é realizada análise de ameaças do arcabouço, e ações de mitigação apresentadas. Ao final, mostra-se que o arcabouço de gerenciamento proposto cumpre com os objetivos e requisitos propostos. / The cloud computing paradigm given its service and deployment models presents several benefits and challenges. One of the main challenges is related to information security, in particular, the compliance contracts between consumers and service provider. Service Level Agreements (SLAs) are contracts in which requirements about service operation and delivery as well as penalties in case of non-compliance of these requirements are defined. A SLA is usually defined in terms of availability and performance requirements, and data security requirements are normally not specified in details as these requirements. The need for security requirements specified in an SLA, especially confidentiality and integrity to the cloud computing paradigm, as well computing architectures to deal with SLA security requirements and management of cloud services based on SLA security requirements in an automated manner during its entire lifecycle are still in evolution, compared to availability requirements. In order to deal with these ineeds, this work aims to propose and evaluate a framework to orchestrate the management of cloud services for the infrastructure as a service (IaaS) based on SLA security requirements, specifically the confidentiality and integrity requirements. The management proposed by the framework comprehend the steps of the SLA lifecycle: i) SLA specification and definition; ii) SLA deployment and management; iii) SLA execute and monitoring; and iv) SLA termination. The validation of proposed framework is performed by its application in a usage scenario, checking the compliance with defined security requirements and specified in the SLA. To ensure the security of proposed framework and its cloud computing environment integration, a threat modeling is performed and mitigation actions are presented. At last, it is shown that the proposed management framework meets the specified framework requirements.

L’informatique en nuage révolutionne complètement la façon de gérer les ressources. Grâce à l’élasticité, les ressources peuvent être provisionnées en quelques minutes pour satisfaire un niveau de qualité de service (QdS) formalisé par un accord de niveau de service (SLA) entre les différents acteurs du nuage. Le principal défi des fournisseurs de services est de maintenir la satisfaction de leurs consommateurs tout en minimisant le coût de ces services. Du point de vue SaaS, ce défi peut être résolu d’une manière ad-hoc par l’allocation/-libération des ressources selon un ensemble de règles prédéfinies avec Amazon Auto Scaling par exemple. Cependant, implémenter finement ces règles d’élasticité n’est pas une tâche triviale. D’une part, la difficulté de profiler la performance d’un service compromet la précision de la planification des ressources. D’autre part, plusieurs paramètres doivent être pris en compte, tels que la multiplication des types de ressources, le temps non-négligeable d’initialisation de ressource et le modèle de facturation IaaS. Cette thèse propose une solution complète pour la gestion des contrats de service du nuage. Nous introduisons CSLA (Cloud ServiceLevel Agreement), un langage dédié à la définition de contrat de service en nuage. Il adresse finement les violations SLA via la dégradation fonctionnelle/QdS et des modèles de pénalité avancés. Nous proposons, ensuite, HybridScale un framework de dimensionnement automatique dirigé par les SLA. Il implémente l’élasticité de façon hybride : gestion réactive-proactive, dimensionnement vertical horizontal et multi-couches (application-infrastructure). Notre solution est validée expérimentalement sur Amazon EC2. / Cloud computing promises to completely revolutionize the way to manage resources. Thanks to elasticity, resources can be provisioning within minutes to satisfy a required level of Quality of Service(QoS) formalized by Service Level Agreements (SLAs) between different Cloud actors. The main challenge of service providers is to maintain its consumer’s satisfaction while minimizing the service costs due to resources fees. For example, from the SaaS point of view, this challenge can be achieved in ad-hoc manner by allocating/releasing resources based on a set of predefined rules as Amazon Auto Scaling implements it. However, doing it right –in a way that maintains end-users satisfaction while optimizing service cost– is not a trivial task. First, because of the difficulty to profile service performance,the accuracy of capacity planning may be compromised. Second, several parameters should be taken into account such as multiple resource types, non-ignorable resource initiation time and IaaS billing model. For that purpose, we propose a complete solution for Cloud Service Level Management. We first introduce CSLA (Cloud Service LevelAgreement), a specific language to describe SLA for Cloud services. It finely expresses SLA violations via functionality/QoS degradationand an advanced penalty model. Then, we propose HybridScale, an auto-scaling framework driven by SLA. It implements the Cloud elasticity in a triple hybrid way : reactive-proactive management, vertical horizontal scaling at cross-layer (application-infrastructure). Our solution is experimentally validated on Amazon EC2.

O paradigma de computação em nuvem, por meio de seus modelos de serviço e implantação, apresenta para os provedores de serviço e consumidores benefícios e desafios. Um dos principais desafios apontados pela área de computação em nuvem é com relação à segurança da informação, especificamente a questão de conformidade com relação a contratos firmados entre o provedor e o consumidor. O acordo de nível de serviço (SLA) é um destes contratos, no qual são estabelecidos requisitos para a entrega e operação do serviço contratado pelo consumidor, bem como penalidades em caso de não atendimento a requisitos estabelecidos no contrato. Comumente, em um SLA definido entre provedor de serviço e consumidor as necessidades de disponibilidade e desempenho com relação ao serviço contratado são especificados, o que não ocorre com relação às necessidades de segurança. A necessidade de especificação de requisitos de segurança em um SLA, em especial confidencialidade e integridade, para o contexto de computação em nuvem, bem como arquiteturas de computação que tratem de requisitos de segurança em um SLA e efetuem o gerenciamento destes requisitos durante o ciclo de vida do SLA, encontram-se em evolução, se comparado aos requisitos de disponibilidade. Considerando a demanda crescente de incorporação de SLA de Segurança nos contratos de serviços de computação em nuvem, este trabalho tem como objetivo propor e avaliar um arcabouço de gerenciamento de serviços de computação em nuvem para o modelo de infraestrutura como serviço (IaaS), tendo como base requisitos de segurança especificados em um SLA, em especial os requisitos de confidencialidade e integridade. O gerenciamento proposto pelo arcabouço contempla as etapas do ciclo de vida de um SLA, que compreende as fases de: i) definir e especificar o SLA; ii) gerenciar e implantar o SLA; iii) executar e gerenciar o SLA e iv) finalizar o SLA. A validação do arcabouço proposto é realizada por meio da sua aplicação em um cenário de uso, onde será verificado o atendimento aos requisitos de segurança definidos e especificados no SLA. Para assegurar que o arcabouço proposto é seguro, bem como a sua integração com o ambiente de computação em nuvem é realizada análise de ameaças do arcabouço, e ações de mitigação apresentadas. Ao final, mostra-se que o arcabouço de gerenciamento proposto cumpre com os objetivos e requisitos propostos. / The cloud computing paradigm given its service and deployment models presents several benefits and challenges. One of the main challenges is related to information security, in particular, the compliance contracts between consumers and service provider. Service Level Agreements (SLAs) are contracts in which requirements about service operation and delivery as well as penalties in case of non-compliance of these requirements are defined. A SLA is usually defined in terms of availability and performance requirements, and data security requirements are normally not specified in details as these requirements. The need for security requirements specified in an SLA, especially confidentiality and integrity to the cloud computing paradigm, as well computing architectures to deal with SLA security requirements and management of cloud services based on SLA security requirements in an automated manner during its entire lifecycle are still in evolution, compared to availability requirements. In order to deal with these ineeds, this work aims to propose and evaluate a framework to orchestrate the management of cloud services for the infrastructure as a service (IaaS) based on SLA security requirements, specifically the confidentiality and integrity requirements. The management proposed by the framework comprehend the steps of the SLA lifecycle: i) SLA specification and definition; ii) SLA deployment and management; iii) SLA execute and monitoring; and iv) SLA termination. The validation of proposed framework is performed by its application in a usage scenario, checking the compliance with defined security requirements and specified in the SLA. To ensure the security of proposed framework and its cloud computing environment integration, a threat modeling is performed and mitigation actions are presented. At last, it is shown that the proposed management framework meets the specified framework requirements.