Automated and dynamic multi-level negotiation framework applied to an efficient cloud provisioning

L’approvisionnement du Cloud est le processus de déploiement et de gestion des applications sur les infrastructures publiques du Cloud. Il est de plus en plus utilisé car il permet aux fournisseurs de services métiers de se concentrer sur leurs activités sans avoir à gérer et à investir dans l’infrastructure. Il comprend deux niveaux d’interaction : (1) entre les utilisateurs finaux et les fournisseurs de services pour l’approvisionnement des applications, et (2) entre les fournisseurs de services et les fournisseurs de ressources pour l’approvisionnement des ressources virtuelles. L’environnement Cloud est devenu un marché complexe où tout fournisseur veut maximiser son profit monétaire et où les utilisateurs finaux recherchent les services les plus efficaces tout en minimisant leurs coûts. Avec la croissance de la concurrence dans le Cloud, les fournisseurs de services métiers doivent assurer un approvisionnement efficace qui maximise la satisfaction de la clientèle et optimise leurs profits.Ainsi, les fournisseurs et les utilisateurs doivent être satisfaits en dépit de leurs besoins contradictoires. La négociation est une solution prometteuse qui permet de résoudre les conflits en comblant le gap entre les capacités des fournisseurs et les besoins des utilisateurs. Intuitivement, la négociation automatique des contrats (SLA) permet d’aboutir à un compromis qui satisfait les deux parties. Cependant, pour être efficace, la négociation automatique doit considérer les propriétés de l’approvisionnement du Cloud et les complexités liées à la dynamicité (dynamicité de la disponibilité des ressources, dynamicité des prix). En fait ces critères ont un impact important sur le succès de la négociation. Les principales contributions de cette thèse répondant au défi de la négociation multi-niveau dans un contexte dynamique sont les suivantes: (1) Nous proposons un modèle de négociateur générique qui considère la nature dynamique de l’approvisionnement du Cloud et son impact potentiel sur les résultats décisionnels. Ensuite, nous construisons un cadre de négociation multicouche fondé sur ce modèle en l’instanciant entre les couches du Cloud. Le cadre comprend des agents négociateurs en communication avec les modules en relation avec la qualité et le prix du service à fournir (le planificateur, le moniteur, le prospecteur de marché). (2) Nous proposons une approche de négociation bilatérale entre les utilisateurs finaux et les fournisseurs de service basée sur une approche d’approvisionnement existante. Les stratégies de négociation sont basées sur la communication avec les modules d’approvisionnement (le planificateur et l’approvisionneur de machines virtuelles) afin d’optimiser les bénéfices du fournisseur de service et de maximiser la satisfaction du client. (3) Afin de maximiser le nombre de clients, nous proposons une approche de négociation adaptative et simultanée comme extension de la négociation bilatérale. Nous proposons d’exploiter les changements de charge de travail en termes de disponibilité et de tarification des ressources afin de renégocier simultanément avec plusieurs utilisateurs non acceptés (c’est-à-dire rejetés lors de la première session de négociation) avant la création du contrat SLA. (4) Afin de gérer toute violation possible de SLA, nous proposons une approche proactive de renégociation après l’établissement de SLA. La renégociation est lancée lors de la détection d’un événement inattendu (par exemple, une panne de ressources) pendant le processus d’approvisionnement. Les stratégies de renégociation proposées visent à minimiser la perte de profit pour le fournisseur et à assurer la continuité du service pour le consommateur. Les approches proposées sont mises en œuvre et les expériences prouvent les avantages d’ajouter la (re)négociation au processus d’approvisionnement. L’utilisation de la (re)négociation améliore le bénéfice du fournisseur, le nombre de demandes acceptées et la satisfaction du client.Cloud provisioning is the process of deployment and management of applications on public cloud infrastructures. Cloud provisioning is used increasingly because it enables business providers to focus on their business without having to manage and invest in infrastructure. Cloud provisioning includes two levels of interaction: (1) between end-users and business providers for application provisioning; and (2) between business providers and resource providers for virtual resource provisioning.The cloud market nowadays is a complex environment where business providers need to maximize their monetary profit, and where end-users look for the most efficient services with the lowest prices. With the growth of competition in the cloud, business providers must ensure efficient provisioning that maximizes customer satisfaction and optimizes the providers’ profit. So, both providers and users must be satisfied in spite of their conflicting needs. Negotiation is an appealing solution to solve conflicts and bridge the gap between providers’ capabilities and users’ requirements. Intuitively, automated Service Level Agreement (SLA) negotiation helps in reaching an agreement that satisfies both parties. However, to be efficient, automated negotiation should consider the properties of cloud provisioning mainly the two interaction levels, and complexities related to dynamicity (e.g., dynamically-changing resource availability, dynamic pricing, dynamic market factors related to offers and demands), which greatly impact the success of the negotiation. The main contributions of this thesis tackling the challenge of multi-level negotiation in a dynamic context are as follows: (1) We propose a generic negotiator model that considers the dynamic nature of cloud provisioning and its potential impact on the decision-making outcome. Then, we build a multi-layer negotiation framework built upon that model by instantiating it among Cloud layers. The framework includes negotiator agents. These agents are in communication with the provisioning modules that have an impact on the quality and the price of the service to be provisioned (e.g, the scheduler, the monitor, the market prospector). (2) We propose a bilateral negotiation approach between end-users and business providers extending an existing provisioning approach. The proposed decision-making strategies for negotiation are based on communication with the provisioning modules (the scheduler and the VM provisioner) in order to optimize the business provider’s profit and maximize customer satisfaction. (3) In order to maximize the number of clients, we propose an adaptive and concurrent negotiation approach as an extension of the bilateral negotiation. We propose to harness the workload changes in terms of resource availability and pricing in order to renegotiate simultaneously with multiple non-accepted users (i.e., rejected during the first negotiation session) before the establishment of the SLA. (4) In order to handle any potential SLA violation, we propose a proactive renegotiation approach after SLA establishment. The renegotiation is launched upon detecting an unexpected event (e.g., resource failure) during the provisioning process. The proposed renegotiation decision-making strategies aim to minimize the loss in profit for the provider and to ensure the continuity of the service for the consumer. The proposed approaches are implemented and experiments prove the benefits of adding (re)negotiation to the provisioning process. The use of (re)negotiation improves the provider’s profit, the number of accepted requests, and the client’s satisfaction

Contributions to Service Level Agreement (SLA), Negotiation and Monitoring in Cloud Computing

Cloud computing is a dynamic field of research, as the latest advances in the cloud computing applications have led to development of a plethora of cloud services in the areas of software, hardware, storage, internet of things connected to the cloud, and 5G supported by the cloud networks. Due to ever increasing developments and the subsequent emergence of a wide range of cloud services, a cloud market was created with cloud providers and customers seeking to buy the cloud services. With the expansion of the cloud market and the presence of a virtual environment in which cloud services are provided and managed, the face to-face meetings between customers and cloud providers is almost impossible, and the negotiation over the cloud services using the state-of-the-art autonomous negotiation agents has been theorized and researched by several researchers in the field of cloud computing, however, the solutions offered by literature are less applicable in the real-time cloud market with the evolving nature of services and customers’ requirements. Therefore, this study aimed to develop the solutions addressing issues in relation to negotiation of cloud services leading to the development of a service-level agreement (SLA), and monitoring of the terms and conditions specified in the SLA. We proposed the autonomous service-level framework supported by the autonomous agents for negotiating over the cloud services on behalf of the cloud providers and customers. The proposed framework contained gathering, filtering, negotiation and SLA monitoring functions, which enhanced its applicability in the real-time cloud market environment. Gathering and filtering stages facilitated the effectiveness of the negotiation phase based on the requirements of customers and cloud services available in the cloud market. The negotiation phase was executed by the selection of autonomous agents, leading to the creation of an SLA with metrics agreed upon between the cloud provider and the customer. Autonomous agents improved the efficiency of negotiation over multiple issues by creating the SLA within a short time and benefiting both parties involved in the negation phase. Rubinstein’s Alternating Offers Protocol was found to be effective in drafting the automated SLA solutions in the challenging environment of the cloud market. We also aimed to apply various autonomous agents to build the new algorithms which can be used to create novel negotiation strategies for addressing the issues in SLAs in cloud computing. The monitoring approach based on the CloudSim tool was found to be an effective strategy for detecting violations against the SLA, which can be an important contribution to building effective monitoring solutions for improving the quality of services in the cloud market

Acceso a la Justicia de los Consumidores a través del ADR y del ODR

El avance de las tecnologías de información y la comunicación nos ha llevado a cambiar nuestra forma de relacionarnos tanto entre nosotros, como con las administraciones. Además, la adquisición de bienes de consumo a través del medio online es cada día más importante para en la economía global y doméstica. Todo ello, llevó a la Unión Europea a la creación del llamado Mercado Único Digital, donde se estableció como uno de los objetivos prioritarios mejorar la tutela efectiva de los ciudadanos comunitarios que realizan compras a través de internet. El presente trabajo tiene por objeto realizar un análisis sobre las facilidades y dificultades que encuentran los consumidores a la hora de acceder a la justicia y a una tutela efectiva de sus pretensiones y reclamaciones de consumo. Para ello ponemos el foco de atención en los planteamientos puramente economicistas que establece la Comisión Europea en la construcción de este Mercado Único Digital, donde hemos dejado de ser ciudadanos con derechos inalienables para pasar a ser un elemento más del mercado, un ítem llamado consumidor. Por ello, para poner en el centro de las políticas de consumo al ciudadano reviviendo la esencia de la democracia europea hemos arrojado luz sobre la importancia de establecer una tutela que proteja a los ciudadanos en sus reclamaciones de consumo, tanto en lo que a su legitimación judicial se refiere, como a las tutelas alternativas del ADR y del ODR de consumo. Estas tutelas alternativas se desarrollan en el nuevo escenario del ADR de consumo en España tras la entrada en vigor de la Ley 7/2017 de 2 de noviembre por la que se incorpora al ordenamiento jurídico español la Directiva 2013/11/UE, del Parlamento Europeo y del Consejo, de 21 de mayo de 2013, relativa a la resolución alternativa de litigios en materia de consumo y la puesta en marcha de la plataforma de ODR de Consumo de la Unión Europea. Por un lado, realizamos propuestas de mejora al actual Sistema Arbitral de Consumo para su adaptación a los estándares de calidad del mercado europeo, en el que está obligado a participar tras la entrada en vigor de la Ley 7/2017. Y, además analizamos la Ley 772017 y señalamos los desarrollos reglamentarios necesarios que precisará. Y, por otro lado, estudiamos el campo del ODR introduciéndonos en los nuevos conceptos Big Data, Internet of Things y legaltech. Posteriormente, realizamos una clasificación de los diferentes procedimientos ODR de consumo más actuales y analizamos la plataforma de ODR de consumo, puesta en marcha por la Comisión Europea tras la entrada en vigor del Reglamento 524/2013, sobre resolución de litigios en línea. Así mismo subrayamos las implementaciones y mejoras que se deben llevar a cabo en la plataforma para poder considerarla una herramienta puramente de ODR y que realmente facilite el acceso a la justicia de los consumidores de la Unión Europea. Finalmente, también realizamos una propuesta de ODR para España, donde estudiamos los puntos concretos que inestimablemente deben desarrollarse para que nuestro país vuelva a estar a la vanguardia de la protección efectiva de las personas consumidoras.Despite the purely business-oriented objectives that give shape to the concept of the Digital Single Market, this thesis aims to defend, without hesitation, the survival of the values, rights, principles and interests of the consumers and users all over the European Union above the economic-driven criteria established by the most neo-liberal approach of the European Union. Therefore, this paper aims to shed light on the protection of the citizens filing consumer claims, especially in connection with their legal standing and the alternative protection provided by the ADR and the ODR. This dissertation also analyses the historical evolution of Consumption Law, the concept of Consumer and the consumers' access to justice in the European Union, where the steps taken by the EU and the waves of access to justice, as theorised by Cappelletti, have shown a parallel evolution. Whereas the European Union of the Single Market strongly encourages us to purchase all kind of goods and services, both in the physical and digital markets, this paper focuses on the citizenry, setting aside the economic-oriented approach that sees consumers as a market element and paying special attention to consumers as citizens with rights

Service level agreement specification for IoT application workflow activity deployment, configuration and monitoring

PhD ThesisCurrently, we see the use of the Internet of Things (IoT) within various domains such as healthcare, smart homes, smart cars, smart-x applications, and smart cities. The number of applications based on IoT and cloud computing is projected to increase rapidly over the next few years. IoT-based services must meet the guaranteed levels of quality of service (QoS) to match users’ expectations. Ensuring QoS through specifying the QoS constraints using service level agreements (SLAs) is crucial. Also because of the potentially highly complex nature of multi-layered IoT applications, lifecycle management (deployment, dynamic reconfiguration, and monitoring) needs to be automated. To achieve this it is essential to be able to specify SLAs in a machine-readable format. currently available SLA specification languages are unable to accommodate the unique characteristics (interdependency of its multi-layers) of the IoT domain. Therefore, in this research, we propose a grammar for a syntactical structure of an SLA specification for IoT. The grammar is based on a proposed conceptual model that considers the main concepts that can be used to express the requirements for most common hardware and software components of an IoT application on an end-to-end basis. We follow the Goal Question Metric (GQM) approach to evaluate the generality and expressiveness of the proposed grammar by reviewing its concepts and their predefined lists of vocabularies against two use-cases with a number of participants whose research interests are mainly related to IoT. The results of the analysis show that the proposed grammar achieved 91.70% of its generality goal and 93.43% of its expressiveness goal. To enhance the process of specifying SLA terms, We then developed a toolkit for creating SLA specifications for IoT applications. The toolkit is used to simplify the process of capturing the requirements of IoT applications. We demonstrate the effectiveness of the toolkit using a remote health monitoring service (RHMS) use-case as well as applying a user experience measure to evaluate the tool by applying a questionnaire-oriented approach. We discussed the applicability of our tool by including it as a core component of two different applications: 1) a contextaware recommender system for IoT configuration across layers; and 2) a tool for automatically translating an SLA from JSON to a smart contract, deploying it on different peer nodes that represent the contractual parties. The smart contract is able to monitor the created SLA using Blockchain technology. These two applications are utilized within our proposed SLA management framework for IoT. Furthermore, we propose a greedy heuristic algorithm to decentralize workflow activities of an IoT application across Edge and Cloud resources to enhance response time, cost, energy consumption and network usage. We evaluated the efficiency of our proposed approach using iFogSim simulator. The performance analysis shows that the proposed algorithm minimized cost, execution time, networking, and Cloud energy consumption compared to Cloud-only and edge-ward placement approaches