A service broker for Intercloud computing

This thesis aims at assisting users in finding the most suitable Cloud resources taking into account their functional and non-functional SLA requirements. A key feature of the work is a Cloud service broker acting as mediator between consumers and Clouds. The research involves the implementation and evaluation of two SLA-aware match-making algorithms by use of a simulation environment. The work investigates also the optimal deployment of Multi-Cloud workflows on Intercloud environments

SLA-driven dynamic cloud resource management

As the size and complexity of Cloud systems increase, the manual management of these solutions becomes a challenging issue as more personnel, resources and expertise are needed. Service Level Agreement (SLA)- aware autonomic cloud solutions enable managing large scale infrastructure management meanwhile supporting multiple dynamic requirement from users. This paper contributes to these topics by the introduction of Cloudcompaas, a SLA-aware PaaS Cloud platform that manages the complete resource lifecycle. This platform features an extension of the SLA specification WS-Agreement, tailored to the specific needs of Cloud Computing. In particular, Cloudcompaas enables Cloud providers with a generic SLA model to deal with higher-level metrics, closer to end-user perception, and with flexible composition of the requirements of multiple actors in the computational scene. Moreover, Cloudcompaas provides a framework for general Cloud computing applications that could be dynamically adapted to correct the QoS violations by using the elasticity features of Cloud infrastructures. The effectiveness of this solution is demonstrated in this paper through a simulation that considers several realistic workload profiles, where Cloudcompaas achieves minimum cost and maximum efficiency, under highly heterogeneous utilization patterns. © 2013 Elsevier B.V. All rights reserved.This work has been developed under the support of the program Formacion de Personal Investigador de Caracter Predoctoral grant number BFPI/2009/103, from the Conselleria d'Educacio of the Generalitat Valenciana. Also, the authors wish to thank the financial support received from The Spanish Ministry of Education and Science to develop the project 'CodeCloud', with reference TIN2010-17804.García García, A.; Blanquer Espert, I.; Hernández García, V. (2014). SLA-driven dynamic cloud resource management. Future Generation Computer Systems. 31:1-11. https://doi.org/10.1016/j.future.2013.10.005S1113

Generic Methods for Adaptive Management of Service Level Agreements in Cloud Computing

The adoption of cloud computing to build and deliver application services has been nothing less than phenomenal. Service oriented systems are being built using disparate sources composed of web services, replicable datastores, messaging, monitoring and analytics functions and more. Clouds augment these systems with advanced features such as high availability, customer affinity and autoscaling on a fair pay-per-use cost model. The challenge lies in using the utility paradigm of cloud beyond its current exploit. Major trends show that multi-domain synergies are creating added-value service propositions. This raises two questions on autonomic behaviors, which are specifically ad- dressed by this thesis. The first question deals with mechanism design that brings the customer and provider(s) together in the procurement process. The purpose is that considering customer requirements for quality of service and other non functional properties, service dependencies need to be efficiently resolved and legally stipulated. The second question deals with effective management of cloud infrastructures such that commitments to customers are fulfilled and the infrastructure is optimally operated in accordance with provider policies. This thesis finds motivation in Service Level Agreements (SLAs) to answer these questions. The role of SLAs is explored as instruments to build and maintain trust in an economy where services are increasingly interdependent. The thesis takes a wholesome approach and develops generic methods to automate SLA lifecycle management, by identifying and solving relevant research problems. The methods afford adaptiveness in changing business landscape and can be localized through policy based controls. A thematic vision that emerges from this work is that business models, services and the delivery technology are in- dependent concepts that can be finely knitted together by SLAs. Experimental evaluations support the message of this thesis, that exploiting SLAs as foundations for market innovation and infrastructure governance indeed holds win-win opportunities for both cloud customers and cloud providers

Business-driven resource allocation and management for data centres in cloud computing markets

Cloud Computing markets arise as an efficient way to allocate resources for the execution of tasks and services within a set of geographically dispersed providers from different organisations. Client applications and service providers meet in a market and negotiate for the sales of services by means of the signature of a Service Level Agreement that contains the Quality of Service terms that the Cloud provider has to guarantee by managing properly its resources. Current implementations of Cloud markets suffer from a lack of information flow between the negotiating agents, which sell the resources, and the resource managers that allocate the resources to fulfil the agreed Quality of Service. This thesis establishes an intermediate layer between the market agents and the resource managers. In consequence, agents can perform accurate negotiations by considering the status of the resources in their negotiation models, and providers can manage their resources considering both the performance and the business objectives. This thesis defines a set of policies for the negotiation and enforcement of Service Level Agreements. Such policies deal with different Business-Level Objectives: maximisation of the revenue, classification of clients, trust and reputation maximisation, and risk minimisation. This thesis demonstrates the effectiveness of such policies by means of fine-grained simulations. A pricing model may be influenced by many parameters. The weight of such parameters within the final model is not always known, or it can change as the market environment evolves. This thesis models and evaluates how the providers can self-adapt to changing environments by means of genetic algorithms. Providers that rapidly adapt to changes in the environment achieve higher revenues than providers that do not. Policies are usually conceived for the short term: they model the behaviour of the system by considering the current status and the expected immediate after their application. This thesis defines and evaluates a trust and reputation system that enforces providers to consider the impact of their decisions in the long term. The trust and reputation system expels providers and clients with dishonest behaviour, and providers that consider the impact of their reputation in their actions improve on the achievement of their Business-Level Objectives. Finally, this thesis studies the risk as the effects of the uncertainty over the expected outcomes of cloud providers. The particularities of cloud appliances as a set of interconnected resources are studied, as well as how the risk is propagated through the linked nodes. Incorporating risk models helps providers differentiate Service Level Agreements according to their risk, take preventive actions in the focus of the risk, and pricing accordingly. Applying risk management raises the fulfilment rate of the Service-Level Agreements and increases the profit of the providerPostprint (published version

Supporting Autonomic Management of Clouds: Service-Level-Agreement, Cloud Monitoring and Similarity Learning

Cloud computing has grown rapidly during the past few years and has become a fundamental paradigm in the Information Technology (IT) area. Clouds enable dynamic, scalable and rapid provision of services through a computer network, usually the Internet. However, managing and optimising clouds and their services in the presence of dynamism and heterogeneity is one of the major challenges faced by industry and academia. A prominent solution is resorting to selfmanagement as fostered by autonomic computing. Self-management requires knowledge about the system and the environment to enact the self-* properties. Nevertheless, the characteristics of cloud, such as large-scale and dynamism, hinder the knowledge discovery process. Moreover, cloud systems abstract the complexity of the infrastructure underlying the provided services to their customers, which obfuscates several details of the provided services and, thus, obstructs the effectiveness of autonomic managers. While a large body of work has been devoted to decisionmaking and autonomic management in the cloud domain, there is still a lack of adequate solutions for the provision of knowledge to these processes. In view of the lack of comprehensive solutions for the provision of knowledge to the autonomic management of clouds, we propose a theoretical and practical framework which addresses three major aspects of this process: (i) the definition of services’ provision through the specification of a formal language to define Service-Level-Agreements for the cloud domain; (ii) the collection and processing of information through an extensible knowledge discovery architecture to monitor autonomic clouds with support to the knowledge discovery process; and (iii) the knowledge discovery through a machine learning methodology to calculate the similarity among services, which can be employed for different purposes, e.g. service scheduling and anomalous behaviour detection. Finally, in a case study, we integrate the proposed solutions and show the benefits of this integration in a hybrid cloud test-bed

Cloud resource orchestration in the multi-cloud landscape: a systematic review of existing frameworks

The number of both service providers operating in the cloud market and customers consuming cloud-based services is constantly increasing, proving that the cloud computing paradigm has successfully delivered its potential. Nevertheless, the unceasing growth of the cloud market is posing hard challenges on its participants. On the provider side, the capability of orchestrating resources in order to maximise profits without failing customers’ expectations is a matter of concern. On the customer side, the efficient resource selection from a plethora of similar services advertised by a multitude of providers is an open question. In such a multi-cloud landscape, several research initiatives advocate the employment of software frameworks (namely, cloud resource orchestration frameworks - CROFs) capable of orchestrating the heterogeneous resources offered by a multitude of cloud providers in a way that best suits the customer’s need. The objective of this paper is to provide the reader with a systematic review and comparison of the most relevant CROFs found in the literature, as well as to highlight the multi-cloud computing open issues that need to be addressed by the research community in the near future

Autonomic Management of Cloud Virtual Infrastructures

The new model of interaction suggested by Cloud Computing has experienced a significant diffusion over the last years thanks to its capability of providing customers with the illusion of an infinite amount of reliable resources. Nevertheless, the challenge of efficiently manage a large collection of virtual computing nodes has just been partially moved from the customer's private datacenter to the larger provider's infrastructure that we generally address as “the cloud”. A lot of effort - in both academic and industrial field - is therefore concentrated on policies for the efficient and autonomous management of virtual infrastructures. The research on this topic is further encouraged by the diffusion of cheap and portable sensors and the availability of almost ubiquitous Internet connectivity that are constantly creating large flows of information about the environment we live in. The need for fast and reliable mechanisms to process these considerable volumes of data has inevitably pushed the evolution from the initial scenario of a single (private or public) cloud towards cloud interoperability, giving birth to several forms of collaboration between clouds. The efficient resource management is further complicated in these heterogeneous environments, making autonomous administration more and more desirable. In this thesis, we initially focus on the challenges of autonomic management in a single-cloud scenario, considering the benefits and shortcomings of centralized and distributed solutions and proposing an original decentralized model. Later in this dissertation, we face the challenge of autonomic management in large interconnected cloud environments, where the movement of virtual resources across the infrastructure nodes is further complicated by the intrinsic heterogeneity of the scenario and difficulties introduced by the higher latency medium between datacenters. According to that, we focus on the cost model for the execution of distributed data-intensive application on multiple clouds and we propose different management policies leveraging cloud interoperability

Integração da Cloud com rede na perspectiva de operador

Mestrado em Engenharia Electrónica e TelecomunicaçõesCloud Computing (CC) tem sido nos últimos tempos um tema bastante mediático no mundo da tecnologia, sendo claras as suas potencialidades tanto em termos económicos como em ciência de recursos. Apesar destas valências, a adopção massiva deste paradigma está ainda condicionada por aspectos relacionados com interoperabilidade, segurança e Quality of Service (QoS). _E no sentido de colmatar estas condicionantes que surge o conceito de Cloud Networking, que consiste na integração das características de CC na rede. Actualmente a infraestrutura de rede _e baseada em tecnologias que foram desenhadas há muitos anos, numa altura em que o contexto e as necessidades do mundo das comunicações eram completamente distintas das necessidades actuais. Este fenómeno tem sido bastante abordado e referido como a ossificação da rede. Esta infra-estrutura é, actualmente, incapaz de dar resposta _as necessidades do CC, características como a dinâmica e flexibilidade não se reflectem na rede. No entanto, a rede e CC não podem ser dissociados, pois _e esta que estabelece uma ponte e permite o acesso a estes recursos por parte dos utilizadores influenciando negativamente o seu uso. No futuro, a virtualização de redes directamente na infra-estrutura dos operadores de rede irá permitir que os utilizadores interajam e utilizem recursos de rede de uma forma similar ao que fazem com os recursos de CC. O problema _e que esta tecnologia ainda está numa fase embrionária e ainda demorara algum tempo até que se torne uma realidade. Se a longo prazo a virtualização de rede deve ser vista como um objectivo a atingir, a curto prazo deverá ser feito um esforço no sentido de trazer algumas das qualidades referidas para as tecnologias de implementação de redes privadas já difundidas entre os operadores de rede. Actualmente as Virtual Private Networks (VPNs) são o mecanismo mais utilizado pelos utilizadores para integrar os recursos de CC com a sua própria infra-estrutura. No entanto, existem limitações porque esta integração _e processada de uma forma estática em escalas de tempo muito superiores aos de CC e na maioria das vezes obrigando os utilizadores a ter que interagir com uma diversidade de operadores. O objectivo principal desta Dissertação _e desenvolver um protótipo que valide o conceito de Cloud Networking utilizando interfaces e protocolos bem definidos, como _e o caso da Open Cloud Networking Interface (OCNI) e Open Cloud Computing Interface (OCCI). Este protótipo ir_a ser capaz de fornecer um serviço integrado de recursos de rede e CC em que o utilizador só irá ter que interagir com um único fornecedor. Isto obriga a que uma linha de comunicação seja estabelecida entre diferentes operadores para uma rápida e automática integração dos dois domínios. Nesta dissertação irão ser apresentados e estudados interfaces e protocolos que facilitem a interoperabilidade entre operadores com vista a sua implementação num protótipo. No domínio da rede irão ser desenvolvidas ferramentas que permitam o aprovisionamento de recursos com vista a integração de CC com a rede do operador. Irá também ser desenvolvido um orquestrador que permita a um utilizador, através de um único pedido, criar uma infra-estrutura que integre recursos de cloud e rede. Posteriormente irão ser efetuados testes de desempenho da instanciação de um serviço integrado de CC com a rede. Ainda no âmbito desta dissertação irá ser estudada uma plataforma de virtualização de rede na qual irão ser feitos testes de trafego sobre a mesma com vista _a sua integração no protótipo

Contribución a la estimulación del uso de soluciones Cloud Computing: Diseño de un intermediador de servicios Cloud para fomentar el uso de ecosistemas distribuidos digitales confiables, interoperables y de acuerdo a la legalidad. Aplicación en entornos multi-cloud.

184 p.El objetivo del trabajo de investigación presentado en esta tesis es facilitar a los desarrolladores y operadores de aplicaciones desplegadas en múltiples Nubes el descubrimiento y la gestión de los diferentes servicios de Computación, soportando su reutilización y combinación, para generar una red de servicios interoperables, que cumplen con las leyes y cuyos acuerdos de nivel de servicio pueden ser evaluados de manera continua. Una de las contribuciones de esta tesis es el diseño y desarrollo de un bróker de servicios de Computación llamado ACSmI (Advanced Cloud Services meta-Intermediator). ACSmI permite evaluar el cumplimiento de los acuerdos de nivel de servicio incluyendo la legislación. ACSmI también proporciona una capa de abstracción intermedia para los servicios de Computación donde los desarrolladores pueden acceder fácilmente a un catálogo de servicios acreditados y compatibles con los requisitos no funcionales establecidos.Además, este trabajo de investigación propone la caracterización de las aplicaciones nativas multiNube y el concepto de "DevOps extendido" especialmente pensado para este tipo de aplicaciones. El concepto "DevOps extendido" pretende resolver algunos de los problemas actuales del diseño, desarrollo, implementación y adaptación de aplicaciones multiNube, proporcionando un enfoque DevOps novedoso y extendido para la adaptación de las prácticas actuales de DevOps al paradigma multiNube