11 research outputs found
Dynamic QoS optimization architecture for cloud-based DDDAS
Cloud computing urges the need for novel on-demand approaches, where the Quality of Service (QoS) requirements of cloud-based services can dynamically and adaptively evolve at runtime as Service Level Agreement (SLA) and environment changes. Given the unpredictable, dynamic and on-demand nature of the cloud, it would be unrealistic to assume that optimal QoS can be achieved at design time. As a result, there is an increasing need for dynamic and self- adaptive QoS optimization solutions to respond to dynamic changes in SLA and the environment. In this context, we posit that the challenge of self-adaptive QoS optimization encompasses two dynamics, which are related to QoS sensitivity and conflicting objectives at runtime. We propose novel design of a dynamic data-driven architecture for optimizing QoS influenced by those dynamics. The architecture leverages on DDDAS primitives by employing distributed simulations and symbiotic feedback loops, to dynamically adapt decision making metaheuristics, which optimizes for QoS tradeoffs in cloud-based systems. We use a scenario to exemplify and evaluate the approach
Architecture-based integrated management of diverse cloud resources
Cloud management faces with great challenges, due to the diversity of Cloud resources and ever-changing management requirements. For constructing a management system to satisfy a specific management requirement, a redevelopment solution based on existing management systems is usually more practicable than developing the system from scratch. However, the difficulty and workload of redevelopment are also very high. As the architecture-based runtime model is causally connected with the corresponding running system automatically, constructing an integrated Cloud management system based on the architecture-based runtime models of Cloud resources can benefit from the model-specific natures, and thus reduce the development workload. In this paper, we present an architecture-based approach to managing diverse Cloud resources. First, manageability of Cloud resources is abstracted as runtime models, which could automatically and immediately propagate any observable runtime changes of target resources to corresponding architecture models, and vice versa. Second, a customized model is constructed according to the personalized management requirement and the synchronization between the customized model and Cloud resource runtime models is ensured through model transformation. Thus, all the management tasks could be carried out through executing programs on the customized model. The experiment on a real-world cloud demonstrates the feasibility, effectiveness and benefits of the new approach to integrated management of Cloud resources ? 2014, Chen et al.; licensee Springer.EI11-15
Self-adaptive and sensitivity-aware QoS modeling for the cloud
Given the elasticity, dynamicity and on-demand nature of the cloud, cloud-based applications require dynamic models for Quality of Service (QoS), especially when the sensitivity of QoS tends to fluctuate at runtime. These models can be autonomically used by the cloud-based application to correctly self-adapt its QoS provision. We present a novel dynamic and self-adaptive sensitivity-aware QoS modeling approach, which is fine-grained and grounded on sound machine learning techniques. In particular, we combine symmetric uncertainty with two training techniques: Auto-Regressive Moving Average with eXogenous inputs model (ARMAX) and Artificial Neural Network (ANN) to reach two formulations of the model. We describe a middleware for implementing the approach. We experimentally evaluate the effectiveness of our models using the RUBiS benchmark and the FIFA 1998 workload trends. The results show that our modeling approach is effective and the resulting models produce better accuracy when compared with conventional models
Multicriteria Resource Brokering in Cloud Computing for Streaming Service
By leveraging cloud computing such as Infrastructure as a Service (IaaS), the outsourcing of computing resources used to support operations, including servers, storage, and networking components, is quite beneficial for various providers of Internet application. With this increasing trend, resource allocation that both assures QoS via Service Level Agreement (SLA) and avoids overprovisioning in order to reduce cost becomes a crucial priority and challenge in the design and operation of complex service-based platforms such as streaming service. On the other hand, providers of IaaS also concern their profit performance and energy consumption while offering these virtualized resources. In this paper, considering both service-oriented and infrastructure-oriented criteria, we regard this resource allocation problem as Multicriteria Decision Making problem and propose an effective trade-off approach based on goal programming model. To validate its effectiveness, a cloud architecture for streaming application is addressed and extensive analysis is performed for related criteria. The results of numerical simulations show that the proposed approach strikes a balance between these conflicting criteria commendably and achieves high cost efficiency
Managing High-Availability and Elasticity in a Cluster Environment
Cloud computing is becoming popular in the computing industry. Elasticity and availability are two features often associated with cloud computing. Elasticity is defined as the automatic provisioning of resources when needed and de-provisioning of resources when they are not needed. Cloud computing offers the users the option of only paying for what they use and guarantees the availability of virtual infrastructure (i.e. virtual machines). The existing cloud solutions handle both elasticity and availability at the virtual infrastructure level through the manipulation, restart, addition and removal of virtual machines (VMs) as required. These solutions equate the application and its workload to the VMs that run the application. High-availability applications are typically composed of redundant resources, and recover from failures through failover mostly managed by a middleware. For such applications, handling elasticity at the virtual infrastructure level through the addition and removal of VMs is not enough, as the availability management in application level will not make use of additional resources. This requires new solutions that manage both elasticity and availability in application level. In this thesis, we provide a solution to manage the elasticity and availability of applications based on a standard middleware defined by the Service Availability Forum (SA Forum). Our solution manages application level elasticity through the manipulation of the application configuration used by the middleware to ensure service availability. For this purpose we introduce a third party, ‘Elasticity Engine’ (EE), that manipulates the application configuration used by the SA Forum middleware when a workload changes. This in turn triggers the SA Forum middleware to change the workload distribution in the system while ensuring service availability. We explore the SA Forum middleware configuration attributes that play a role in elasticity management, the constraints applicable to them, as well as their impact on the load distribution. We propose an overall architecture for availability and elasticity management for an SA Forum system. We design the EE architecture and behavior through a set of strategies for elasticity. The proposed EE has been implemented and tested
Gerenciamento de nuvem computacional usando critérios de segurança
Orientador: Paulo Lício de GeusTese (doutorado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: A nuvem computacional introduziu novas tecnologias e arquiteturas, mudando a computação empresarial. Atualmente, um grande número de organizações optam por utilizar arquiteturas computacionais tradicionais por considerarem esta tecnologia não confiável, devido a problemas não resolvidos relacionados a segurança e privacidade. Em particular, quanto á contratação de um serviço na nuvem, um aspecto importante é a forma como as políticas de segurança serão aplicadas neste ambiente caracterizado pela virtualização e serviços em grande escala de multi-locação. Métricas de segurança podem ser vistas como ferramentas para fornecer informações sobre o estado do ambiente. Com o objetivo de melhorar a segurança na nuvem computacional, este trabalho apresenta uma metodologia para a gestão da nuvem computacional usando a segurança como um critério, através de uma arquitetura para monitoramento da segurança com base em acordos de níveis de serviço de segurança Security-SLA para serviços de IaaS, PaaS e SaaS, que usa métricas de segurançaAbstract: Cloud Computing has introduced new technology and architectures that changed enterprise computing. Currently, there is a large number of organizations that choose to stick to traditional architectures, since this technology is considered unreliable due to yet unsolved problems related to security and privacy. In particular, when hiring a service in the cloud, an important aspect is how security policies will be applied in this environment characterized by both virtualization and large-scale multi-tenancy service. Security metrics can be seen as tools to provide information about the status of the environment. Aimed at improving security in the Cloud Computing, this work presents a methodology for Cloud Computing management using security as a criterion, across an architecture for security monitoring based on Security-SLA for IaaS, PaaS and SaaS services using security metricsDoutoradoCiência da ComputaçãoDoutor em Ciência da Computação23/200.308/2009FUNDEC
Integração do paradigma de cloud computing com a infraestrutura de rede do operador
Doutoramento em Engenharia InformáticaThe proliferation of Internet access allows that users have the possibility to use
services available directly through the Internet, which translates in a change of
the paradigm of using applications and in the way of communicating,
popularizing in this way the so-called cloud computing paradigm. Cloud
computing brings with it requirements at two different levels: at the cloud level,
usually relying in centralized data centers, where information technology and
network resources must be able to guarantee the demand of such services;
and at the access level, i.e., depending on the service being consumed,
different quality of service is required in the access network, which is a Network
Operator (NO) domain. In summary, there is an obvious network dependency.
However, the network has been playing a relatively minor role, mostly as a
provider of (best-effort) connectivity within the cloud and in the access network.
The work developed in this Thesis enables for the effective integration of cloud
and NO domains, allowing the required network support for cloud. We propose
a framework and a set of associated mechanisms for the integrated
management and control of cloud computing and NO domains to provide endto-
end services. Moreover, we elaborate a thorough study on the embedding of
virtual resources in this integrated environment. The study focuses on
maximizing the host of virtual resources on the physical infrastructure through
optimal embedding strategies (considering the initial allocation of resources as
well as adaptations through time), while at the same time minimizing the costs
associated to energy consumption, in single and multiple domains.
Furthermore, we explore how the NO can take advantage of the integrated
environment to host traditional network functions. In this sense, we study how
virtual network Service Functions (SFs) should be modelled and managed in a
cloud environment and enhance the framework accordingly.
A thorough evaluation of the proposed solutions was performed in the scope of
this Thesis, assessing their benefits. We implemented proof of concepts to
prove the added value, feasibility and easy deployment characteristics of the
proposed framework. Furthermore, the embedding strategies evaluation has
been performed through simulation and Integer Linear Programming (ILP)
solving tools, and it showed that it is possible to reduce the physical
infrastructure energy consumption without jeopardizing the virtual resources
acceptance. This fact can be further increased by allowing virtual resource
adaptation through time. However, one should have in mind the costs
associated to adaptation processes. The costs can be minimized, but the virtual
resource acceptance can be also reduced. This tradeoff has also been subject
of the work in this Thesis.A proliferação do acesso à Internet permite aos utilizadores usar serviços
disponibilizados diretamente através da Internet, o que se traduz numa
mudança de paradigma na forma de usar aplicações e na forma de comunicar,
popularizando desta forma o conceito denominado de cloud computing. Cloud
computing traz consigo requisitos a dois níveis: ao nível da própria cloud,
geralmente dependente de centros de dados centralizados, onde as
tecnologias de informação e recursos de rede têm que ser capazes de garantir
as exigências destes serviços; e ao nível do acesso, ou seja, dependendo do
serviço que esteja a ser consumido, são necessários diferentes níveis de
qualidade de serviço na rede de acesso, um domínio do operador de rede. Em
síntese, existe uma clara dependência da cloud na rede. No entanto, o papel
que a rede tem vindo a desempenhar neste âmbito é reduzido, sendo
principalmente um fornecedor de conectividade (best-effort) tanto no dominio
da cloud como no da rede de acesso.
O trabalho desenvolvido nesta Tese permite uma integração efetiva dos
domínios de cloud e operador de rede, dando assim à cloud o efetivo suporte
da rede. Para tal, apresentamos uma plataforma e um conjunto de
mecanismos associados para gestão e controlo integrado de domínios cloud
computing e operador de rede por forma a fornecer serviços fim-a-fim. Além
disso, elaboramos um estudo aprofundado sobre o mapeamento de recursos
virtuais neste ambiente integrado. O estudo centra-se na maximização da
incorporação de recursos virtuais na infraestrutura física por meio de
estratégias de mapeamento ótimas (considerando a alocação inicial de
recursos, bem como adaptações ao longo do tempo), enquanto que se
minimizam os custos associados ao consumo de energia. Este estudo é feito
para cenários de apenas um domínio e para cenários com múltiplos domínios.
Além disso, exploramos como o operador de rede pode aproveitar o referido
ambiente integrado para suportar funções de rede tradicionais. Neste sentido,
estudamos como as funções de rede virtualizadas devem ser modeladas e
geridas num ambiente cloud e estendemos a plataforma de acordo com este
conceito.
No âmbito desta Tese foi feita uma avaliação extensa das soluções propostas,
avaliando os seus benefícios. Implementámos provas de conceito por forma a
demonstrar as mais-valias, viabilidade e fácil implantação das soluções
propostas. Além disso, a avaliação das estratégias de mapeamento foi
realizada através de ferramentas de simulação e de programação linear inteira,
mostrando que é possível reduzir o consumo de energia da infraestrutura
física, sem comprometer a aceitação de recursos virtuais. Este aspeto pode
ser melhorado através da adaptação de recursos virtuais ao longo do tempo.
No entanto, deve-se ter em mente os custos associados aos processos de
adaptação. Os custos podem ser minimizados, mas isso implica uma redução
na aceitação de recursos virtuais. Esta compensação foi também um tema
abordado nesta Tese