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.

Made available in DSpace on 2016-12-23T14:05:55Z (GMT). No. of bitstreams: 1 Leandro Anselmo Neto.pdf: 964186 bytes, checksum: b3efff8fe8d4906b378dc4ae5f762c60 (MD5) Previous issue date: 2010-11-24 / Este trabalho tem como objetivo propor uma metodologia para avaliação do nível de serviço das vias urbanas, de forma complementar ao método de classificação do Manual de Capacidade de Vias - HCM, multifaixas com adição de duas variáveis: emissão de poluentes e custo do tempo de produção perdido. Inicialmente,faz-se revisão bibliográfica sobre perda de tempo no trânsito, consequente poluição gerada e gerenciamento de demanda.Em seguida, discorre-se sobre a análise de vias e medidas de desempenho importantes para manutenção do padrão aceitável de fluidez e, também,sobre o procedimento para análise de capacidade e o cálculo do nível de serviço,usando o HCM. Considerando a importância da preservação do meio ambiente e do valor do tempo para a sociedade, no mundo moderno, propõese uma parte complementar valorizando-se as variáveis adicionadas, submetidas a métodos estatísticos, o que pode implicar num enquadramento variável de nível de serviço,isto é, uma reclassificação que constitui uma inovação da metodologia proposta. A partir de dados coletados em campo em instituições públicas e privadas, ensaiou-se esta metodologia para um dos acessos mais importantes da cidade de Vitória, que é a Ponte Darcy Castelo de Mendonça (3ª Ponte), que liga Vitória e Vila Velha e com capacidade prevista comprometida e alto custo de tempo de produção perdido. Após as análises dos resultados gerados no ensaio, corroborando com o HCM, inferiu-se que há perda de tempo de produção apenas em dois níveis - D,E, assim, decidiu-se calcular o respectivo custo e não considerá-lo estatisticamente na metodologia proposta. Já a emissão de poluentes, no caso do CO, observou-se ser relevante em todos os níveis - A,B,C,D,E, sendo aplicadas técnicas estatísticas multivariadas para proceder-se à reclassificação de 19% dos níveis calculados e julgados como prejudicados. Vale salientar que a metodologia proposta pode ser aplicada a qualquer via urbana / This paper aims to propose a methodology for assessing the level of service of urban roads, in a complementary manner to the method of Classification of the Manual of the routes Capacity - HCM, multitracks with the addition of two variables: the emission of pollutants and cost of lost production time. Initially, it is made a literature review on time loss, pollution generated by traffic and demand management. Then, we talk about the importance of track analysis and performance measures important to keep a track with an acceptable standard of fluidity, and also about the procedure for capacity analysis and the calculation of the level of service, using the HCM. Considering the importance of preserving the environment and the time value to society in the modern world, we propose a complementary part valuing the added variables, subjected to statistical methods, which may involve a background variable service level, ie, a reclassification that is an innovation of the proposed methodology. From the data collected in the field of public and private institutions, it was rehearsed this methodology for one of the most important accesses to the city of Victoria which is the Darcy Castelo de Mendonça Bridge (3ª Bridge) that links up Vitoria and Vila Velha and with compromised planned capacity and high cost of lost production time. After the analysis of the results generated in the test, corroborating with HCM, we inferred that there is loss of production time in two stages - D, E. Thus, it was decided to calculate the cost and not consider it statistically to reclassify the service level. The emission of pollutants - CO - was observed to be relevant at all levels - A, B, C, D, E, and it was applied multivaried statistical techniques to proceed the reclassification of 19% of the level calculated and judged as impaired. It is worth pointing out that the proposed methodology can be applied to any urban road

Made available in DSpace on 2016-12-23T14:07:28Z (GMT). No. of bitstreams: 1 DissertacaoMestradoRodrigoBonfaDrago.pdf: 3999277 bytes, checksum: b9b03d58f60a9f3c894c805a35a87dcc (MD5) Previous issue date: 2006-04-12 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The increasing complexity in the networks and applications with the new demands for distributed information technology (IT) services has changed the way systems are managed. The focus has moved from device-oriented management to service-oriented management. Currently, small and large companies demand an IT infrastructure to support their business, and such infrasctructure has to be monitored. Quantitative metrics should be measured and used to get a feedback about the IT environment functionalities. This work proposes a web-based network service management system that use open standards and free software to help the practice of Service Level Management (SLM) at IT environments. A metric here named Service Availability Index - is presented as a way to measure the IT environment system functionalities. To validate the prototype developed for the system proposed, a case study is presented and the main results are analyzed. / Devido ao crescimento da complexidade das redes e aplicações e à necessidade de serviços de TI (Tecnologia da Informação) distribuídos, houve uma mudança na forma pela qual os sistemas são gerenciados. O foco moveu-se da gerência orientada a dispositivos para a gerência orientada a serviços. Atualmente, pequenas e grandes organizações precisam de uma infra-estrutura de TI para suportar seus negócios, e esta infra-estrutura deve ser monitorada a fim de garantir o seu bom funcionamento. Métricas quantitativas devem ser medidas e utilizadas para se obter um feedback a respeito do funcionamento do ambiente de TI. Este trabalho propõe um sistema de gerência de serviços de rede, baseado em web, que utiliza padrões abertos e software livre, para ajudar na prática do Gerenciamento de Nível de Serviço (SLM Service Level Management) em ambientes de TI. Uma métrica aqui chamada de Índice de Disponibilidade de Sistema - IDS é considerada como uma maneira de medir a funcionalidade dos sistemas de ambientes de TI. A fim de validar o protótipo desenvolvido para o sistema proposto, um estudo de caso é apresentado e os principais resultados são analisados.

Made available in DSpace on 2015-04-22T22:10:11Z (GMT). No. of bitstreams: 1 Armando.pdf: 1186614 bytes, checksum: 973e53495ff1fde59e3b83ca719dc6a3 (MD5) Previous issue date: 2005-11-18 / The present work has as objective to present a proposal for monitoring of the service level to systems of physical distribution of products that seeks to bring improvements to the delivery process of the companies that act in the beverages segment. By means of an extensive literature review and of the case study accomplished in a company of beverage segment, it became possible to map all distribution process and identify the variables that affect it s performance, concentrating the monitor on the indicators of costs, productivity, use of resources, efficiency and route come back. Regarding that physical distribution of products absorbs significant portion of the budget expenses of the organizations, this activity has occupied a prominence paper in the logistics problems of the companies. That is due, on a side, to the growing cost of the capital (financial cost), that forces the companies to reduce the stocks and the handling activity, transports and distribution of your products beyond own competition. The model was applied and it presented satisfactory results that allowed the company to identify, measure, analyze, improve and control the level service of your distribution system. The proposal contemplates a systematic accompaniment of the indicators and its performance, along the year of 2004 and, with possibility of definitions or revision of the goals as well as the comparison with other periods. / O presente trabalho tem como objetivo apresentar uma proposta de monitoramento do nível de serviço para sistemas de distribuição física de produtos que vise trazer melhorias ao processo de entrega das empresas que atuam no segmento de bebidas. Mediante extensa revisão de literatura e do estudo de caso realizado em uma empresa do segmento de bebidas, tornou-se possível mapear todo o processo de distribuição e identificar as variáveis que afetam o seu desempenho, concentrando o monitoramento nos indicadores de custos, produtividade, utilização de recursos, eficiência e retorno de rota. Considerando que a distribuição física de produtos absorve parcela significativa do orçamento de despesas das organizações, essa atividade passou a ocupar um papel de destaque nos problemas logísticos das empresas. Isso se deve, de um lado, ao custo crescente do capital (custo financeiro), que força as empresas a reduzir os estoques e a agilizar o manuseio, transporte e distribuição de seus produtos além da própria concorrência. O modelo foi aplicado e apresentou resultados satisfatórios que permitiram a empresa identificar, medir, analisar, melhorar e controlar o nível de serviço de seu sistema de distribuição. A proposta contempla um acompanhamento sistemático dos indicadores e seus resultados, ao longo do ano de 2004 e, com possibilidade de definições ou revisão das metas bem como a comparação com outros períodos.

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.

Increasing cycling as a means of personal travel couldgenerate environmental benefits if associated with acorresponding decrease in car-based transport. In seeking topromote cycling in wintertime, it is desirable to understandhow important the road surface condition is compared to otherfactors in people's decision to cycle or not. In this thesis,the possibility of increasing the number of cyclists byimproving the winter maintenance servicelevel on cycleways isexamined. The attitudes towards cycling during winter ingeneral, and in relation to winter maintenance of cycleways inparticular, is studied through questionnaire surveys. Bicyclemeasurements are related to weather data from Road WeatherInformation System, in order to know the influence on cycleflow during winter from different weather factors. Fieldstudies are performed testing unconventional winter maintenancemethods, in order to see if a higher service level could beachieved on cycleways and if that would lead to an increase inwinter cycling frequency. The field studies are evaluatedthrough road condition observations, measurements of friction,bicycle counts, a questionnaire survey and interviews. A visualmethod to assess winter road conditions on cycleways isdeveloped, in order to compare the service levels achievedusing different winter maintenance methods. There is a clear difference in mode choice between seasons.With improved winter maintenance service level it could bepossible to increase the number of bicycle trips to work duringwinter with, at the most, 18 %, and decrease the number of cartrips with 6 %. However, it could not be concluded with bicyclemeasurements, that an enhanced service level in fact, generateda higher winter cycling frequency. To increase cycling during winter, snow clearance is themost important maintenance measure. Skid control is not assignificant for the choice of mode but is important to attendto for safety reasons. Winter road condition propertiesimportant both with regard to safety and accessibility ofcyclists, are icy tracks formed when wet snow freezes, snowdepths greater than about 3 cm of loose snow or slush,unevenness in a snow covered surface, loose grit on a baresurface. Weather factors with negative influence on winter cyclingfrequency, are temperatures below +5 ° C,precipitationand strong winds. Only the occurrence of precipitation, not theamount of rain or snow, is significant for the cycle flow. Lowtemperatures are more important in reducing the cycle flow thanprecipitation. Temperatures around 0 ° C seem to be extracritical for cyclists, probably due to the larger influence ofprecipitation and slippery road conditions at thesetemperatures. An unconventional method using a power broom for snowclearance and brine or pre-wetted salt for de-icing, provides ahigher service level than winter maintenance methodstraditionally used, but it is about 2 to 3 times moreexpensive. The method has great potential in regions, such assouthern Sweden, with low snow accumulations but with major iceformation problems. To assess the maintenance service level,the visual assessment method developed and tested in thisproject is adequate for the purpose, however, furtherimprovements are desirable. As a complement to the visualassessment, a Portable Friction Tester can be used to measurethe surface friction on cycleways during wintertime. Keywords:Cycleways, winter maintenance, maintenanceservice level, mode choice, winter cycling frequency, wintermaintenance equipment, winter road condition assessment,bicycle measurements, friction measurement.

<p> <p>&nbsp / </p> </p> <p align="left">The underlying theme of this thesis is identification, classification, detection and prediction of cellular network faults using state of the art technologies, methods and algorithms.</p>

In mobile and wireless networks, data broadcasting for popular data items enables the efficient utilization of the limited wireless bandwidth. However, efficient data scheduling schemes are needed to fully exploit the benefits of data broadcasting. Towards this goal, several broadcast scheduling policies have been proposed. These existing schemes have mostly focused on either minimizing response time, or drop rate, when requests are associated with hard deadlines. The inherent inaccuracy of hard deadlines in a dynamic mobile environment motivated us to use Service Level Agreements (SLAs) where a user specifies the utility of data as a function of its arrival time. Moreover, SLAs provide the mobile user with an already familiar quality of service specification from wired environments. Hence, in this dissertation, we propose SAAB, an SLA-aware adaptive data broadcast scheduling policy for maximizing the system utility under SLA-based performance measures. To achieve this goal, SAAB considers both the characteristics of disseminated data objects as well as the SLAs associated with them. Additionally, SAAB automatically adjusts to the system workload conditions which enables it to constantly outperform existing broadcast scheduling policies.

In mobile and wireless networks, data broadcasting for popular data items enables the efficient utilization of the limited wireless bandwidth. However, efficient data scheduling schemes are needed to fully exploit the benefits of data broadcasting. Towards this goal, several broadcast scheduling policies have been proposed. These existing schemes have mostly focused on either minimizing response time, or drop rate, when requests are associated with hard deadlines. The inherent inaccuracy of hard deadlines in a dynamic mobile environment motivated us to use Service Level Agreements (SLAs) where a user specifies the utility of data as a function of its arrival time. Moreover, SLAs provide the mobile user with an already familiar quality of service specification from wired environments. Hence, in this dissertation, we propose SAAB, an SLA-aware adaptive data broadcast scheduling policy for maximizing the system utility under SLA-based performance measures. To achieve this goal, SAAB considers both the characteristics of disseminated data objects as well as the SLAs associated with them. Additionally, SAAB automatically adjusts to the system workload conditions which enables it to constantly outperform existing broadcast scheduling policies.

<p>Increasing cycling as a means of personal travel couldgenerate environmental benefits if associated with acorresponding decrease in car-based transport. In seeking topromote cycling in wintertime, it is desirable to understandhow important the road surface condition is compared to otherfactors in people's decision to cycle or not. In this thesis,the possibility of increasing the number of cyclists byimproving the winter maintenance servicelevel on cycleways isexamined. The attitudes towards cycling during winter ingeneral, and in relation to winter maintenance of cycleways inparticular, is studied through questionnaire surveys. Bicyclemeasurements are related to weather data from Road WeatherInformation System, in order to know the influence on cycleflow during winter from different weather factors. Fieldstudies are performed testing unconventional winter maintenancemethods, in order to see if a higher service level could beachieved on cycleways and if that would lead to an increase inwinter cycling frequency. The field studies are evaluatedthrough road condition observations, measurements of friction,bicycle counts, a questionnaire survey and interviews. A visualmethod to assess winter road conditions on cycleways isdeveloped, in order to compare the service levels achievedusing different winter maintenance methods.</p><p>There is a clear difference in mode choice between seasons.With improved winter maintenance service level it could bepossible to increase the number of bicycle trips to work duringwinter with, at the most, 18 %, and decrease the number of cartrips with 6 %. However, it could not be concluded with bicyclemeasurements, that an enhanced service level in fact, generateda higher winter cycling frequency.</p><p>To increase cycling during winter, snow clearance is themost important maintenance measure. Skid control is not assignificant for the choice of mode but is important to attendto for safety reasons. Winter road condition propertiesimportant both with regard to safety and accessibility ofcyclists, are icy tracks formed when wet snow freezes, snowdepths greater than about 3 cm of loose snow or slush,unevenness in a snow covered surface, loose grit on a baresurface.</p><p>Weather factors with negative influence on winter cyclingfrequency, are temperatures below +5 ° C,precipitationand strong winds. Only the occurrence of precipitation, not theamount of rain or snow, is significant for the cycle flow. Lowtemperatures are more important in reducing the cycle flow thanprecipitation. Temperatures around 0 ° C seem to be extracritical for cyclists, probably due to the larger influence ofprecipitation and slippery road conditions at thesetemperatures.</p><p>An unconventional method using a power broom for snowclearance and brine or pre-wetted salt for de-icing, provides ahigher service level than winter maintenance methodstraditionally used, but it is about 2 to 3 times moreexpensive. The method has great potential in regions, such assouthern Sweden, with low snow accumulations but with major iceformation problems. To assess the maintenance service level,the visual assessment method developed and tested in thisproject is adequate for the purpose, however, furtherimprovements are desirable. As a complement to the visualassessment, a Portable Friction Tester can be used to measurethe surface friction on cycleways during wintertime.</p><p><b>Keywords:</b>Cycleways, winter maintenance, maintenanceservice level, mode choice, winter cycling frequency, wintermaintenance equipment, winter road condition assessment,bicycle measurements, friction measurement.</p>