Network performance of multiple virtual machine live migration in cloud federations

The idea of pay-per-use computing incarnated by the cloud paradigm is gaining a lot of success, both for entertainment and business applications. As a consequence, the demand for computing, storage and communication resources to be deployed in data center infrastructures is increasing dramatically. This trend is fostering new forms of infrastructure sharing such as cloud federations, where the excess workload is smartly distributed across multiple data centers, following some kind of mutual agreement among the participating cloud providers. Federated clouds can obtain great advantages from virtualization technologies and, in particular, from multiple virtual machine live migration techniques, which allow to flexibly move bulk workload across heterogeneous computing environments with minimal service disruption. However, a quantitative characterization of the performance of the inter-data center network infrastructure underlying the cloud federation is essential to guarantee user's quality of service and optimize provider's resource utilization. The main contribution of this paper is the definition and application of an analytical model for dimensioning inter-data center network capacity in order to achieve some given performance levels, assuming some simple multiple virtual machine live migration strategies. An extensive set of results are provided that allow to understand the impact of the many parameters involved in the design of a cloud federation network

A Survey on Load Balancing Algorithms for VM Placement in Cloud Computing

The emergence of cloud computing based on virtualization technologies brings huge opportunities to host virtual resource at low cost without the need of owning any infrastructure. Virtualization technologies enable users to acquire, configure and be charged on pay-per-use basis. However, Cloud data centers mostly comprise heterogeneous commodity servers hosting multiple virtual machines (VMs) with potential various specifications and fluctuating resource usages, which may cause imbalanced resource utilization within servers that may lead to performance degradation and service level agreements (SLAs) violations. To achieve efficient scheduling, these challenges should be addressed and solved by using load balancing strategies, which have been proved to be NP-hard problem. From multiple perspectives, this work identifies the challenges and analyzes existing algorithms for allocating VMs to PMs in infrastructure Clouds, especially focuses on load balancing. A detailed classification targeting load balancing algorithms for VM placement in cloud data centers is investigated and the surveyed algorithms are classified according to the classification. The goal of this paper is to provide a comprehensive and comparative understanding of existing literature and aid researchers by providing an insight for potential future enhancements.Comment: 22 Pages, 4 Figures, 4 Tables, in pres

Migration of an On-Premise Single-Tenant Enterprise Application to the Azure Cloud: The Multi-Tenancy Case Study

Kokkuvõte Pilvearvutuse edu muudab radikaalselt tavasid kuidas edaspidi infotehnoloogia teenuseid arendatakse, juurutatakse ja hallatakse. Sellest tulenevalt on sõnakõlks „pilve migratsioon“ vägagi aktuaalne paljudes ettevõtetes. Tänu sellele tehnoloogiale on paljud suured ja väikesed ettevõtted huvitatud enda tarkvara, andmebaasi süsteemide ja infrastruktuuri üleviimisest pilve keskkonda. Olemasolevate süsteemide migreerimine pilve võib vähendada kulutusi, mis on seotud vajamineva riistvara, tarkvara paigaldamise ning litsentseerimisega ja samuti selle kõige haldamiseks vajaminevate inimeste palkamisega. Rakenduse ja selle andmete hoidmine pilves, mis teenindab mitmeid üürnike (ik. tenants) võib osutuda kalliks kui ei kasutada jagatud lähenemist üürnike vahel. Sellest tulenevalt on teadlikult disainitud rakenduse ning andme arhitektuur äärmiselt oluline organisatsioonile, mis kasutab mitme-üürniku (ik. multi-tenant) lähenemist. Käesolevas magistritöös kirjeldatakse juhtumiuuringut (ik. case study) ning saadud kogemusi eraldiseiseva majasiseselt paigaldatava rakenduse migreerimisel Azure pilve keskkonda. Töö kirjeldab juristidele mõeldud tootlikkuse mõõtmise tarkvara andmekihi migreerimist Azure pilvekeskkonda. Majasisese ühe tarbijaga tarkvara andmekihi üleviimine efektiivsele mitme-üürniku andmekandja süsteemi pilve keskkonnas nõuab lisaks ka kõrgetasemelise autentimis-mehhanismi disainimist ning realiseerimist. Töö põhirõhk on turvalise skaleeruva ning mitme-üürniku efektiivse andmekandja süsteemi arhitektuuri disainimine ning realiseerimine pilve-keskkonda. Projektis kasutatakse SQL Database’i (endine SQL Azure) poolt pakutavat sisse ehitatud võimekust (SQL Federations) selleks, et tagada turvaline andmete eraldatus erinevate üürnike vahel ja andmebaasi skaleeruvus. Tarkvara andmekihi migreerimine pilve keskkonda toob kaasa kulude vähenemis, mis on seotud tarkvara tarnimisega, paigaldamise ning haldamisega. Lisaks aitab see ettevõttel laieneda uutele turgudele, mis enne migreerimist oli takistatud kohapeal teostava tarkvara paigaldamisega. Tänu pilves olevale andmekihile nõuab uuele kliendile süsteemi paigaldamine väga väikest kulutust.The success of cloud computing is changing the way how information technology services are developed, deployed, maintained and scaled. This makes the ‘migration to the cloud’ a buzzword in the industry for most of the enterprises today. Observing so many advantages of this phenomenon technology, enterprises from small to large scales are interested in migrating their software applications, database systems or infrastructures to cloud scale solutions. Migrating existing systems to a cloud scale solution can reduce the expenses related to costs of the necessary hardware for servers, installation of the operating system environment, license costs of the operating system and database products, deployment of the database products and hiring professional staff for keeping the system up and running. However, storing the application data to a back-end that serves multiple tenants on the cloud will be also costly if the resources on the cloud platform are not shared fairly among tenants. Thus, a carefully designed multi-tenant architecture is essential for an organization that serves multiple tenants. In this master thesis, we will describe a case study and lessons learned on the migration of an enterprise application from an on-premise deployment backend to the Azure Cloud. More specifically, the thesis describes the migration of a productivity tool specialized for legal professionals to a multi-tenant data storage back-ends on Azure Cloud. Moving an on-premise, single-tenant software backend to a multi-tenant data storage system on the cloud will also require design and implementation of authentication mechanisms. The core focus of the work consists of the design and implementation of a secure, scalable and multi-tenant efficient data storage system and application architecture on the cloud. SQL Database (formerly SQL Azure) offers native features (SQL Federations) for the secure isolation of the data among tenants and database scalability which has been used inside the project. Furthermore, the basic application authentication mechanism is enhanced with identity providers such as Google Account and Windows Live ID by embedding native functionality of Windows Azure called Azure Access Control Service to the login mechanism. Migration of the software backend to a cloud scale solution is expected to reduce the costs related to delivery, deployment, maintenance and operation of the software for the business. Furthermore, it will help the business to target new markets since it is a cloud based solution and requires very little initial effort to deliver the software to the new customers

Strategies for Increased Energy Awareness in Cloud Federations

This chapter first identifies three scenarios that current energy aware cloud solutions cannot handle as isolated IaaS, but their federative efforts offer opportunities to be explored. These scenarios are centered around: (i) multi-datacenter cloud operator, (ii) commercial cloud federations, (iii) academic cloud federations. Based on these scenarios, we identify energy-aware scheduling policies to be applied in the management solutions of cloud federations. Among others, these policies should consider the behavior of independent administrative domains, the frequently contradicting goals of the participating clouds and federation wide energy consumption

Security in Cloud Computing: Evaluation and Integration

Au cours de la dernière décennie, le paradigme du Cloud Computing a révolutionné la manière dont nous percevons les services de la Technologie de l’Information (TI). Celui-ci nous a donné l’opportunité de répondre à la demande constamment croissante liée aux besoins informatiques des usagers en introduisant la notion d’externalisation des services et des données. Les consommateurs du Cloud ont généralement accès, sur demande, à un large éventail bien réparti d’infrastructures de TI offrant une pléthore de services. Ils sont à même de configurer dynamiquement les ressources du Cloud en fonction des exigences de leurs applications, sans toutefois devenir partie intégrante de l’infrastructure du Cloud. Cela leur permet d’atteindre un degré optimal d’utilisation des ressources tout en réduisant leurs coûts d’investissement en TI. Toutefois, la migration des services au Cloud intensifie malgré elle les menaces existantes à la sécurité des TI et en crée de nouvelles qui sont intrinsèques à l’architecture du Cloud Computing. C’est pourquoi il existe un réel besoin d’évaluation des risques liés à la sécurité du Cloud durant le procédé de la sélection et du déploiement des services. Au cours des dernières années, l’impact d’une efficace gestion de la satisfaction des besoins en sécurité des services a été pris avec un sérieux croissant de la part des fournisseurs et des consommateurs. Toutefois, l’intégration réussie de l’élément de sécurité dans les opérations de la gestion des ressources du Cloud ne requiert pas seulement une recherche méthodique, mais aussi une modélisation méticuleuse des exigences du Cloud en termes de sécurité. C’est en considérant ces facteurs que nous adressons dans cette thèse les défis liés à l’évaluation de la sécurité et à son intégration dans les environnements indépendants et interconnectés du Cloud Computing. D’une part, nous sommes motivés à offrir aux consommateurs du Cloud un ensemble de méthodes qui leur permettront d’optimiser la sécurité de leurs services et, d’autre part, nous offrons aux fournisseurs un éventail de stratégies qui leur permettront de mieux sécuriser leurs services d’hébergements du Cloud. L’originalité de cette thèse porte sur deux aspects : 1) la description innovatrice des exigences des applications du Cloud relativement à la sécurité ; et 2) la conception de modèles mathématiques rigoureux qui intègrent le facteur de sécurité dans les problèmes traditionnels du déploiement des applications, d’approvisionnement des ressources et de la gestion de la charge de travail au coeur des infrastructures actuelles du Cloud Computing. Le travail au sein de cette thèse est réalisé en trois phases.----------ABSTRACT: Over the past decade, the Cloud Computing paradigm has revolutionized the way we envision IT services. It has provided an opportunity to respond to the ever increasing computing needs of the users by introducing the notion of service and data outsourcing. Cloud consumers usually have online and on-demand access to a large and distributed IT infrastructure providing a plethora of services. They can dynamically configure and scale the Cloud resources according to the requirements of their applications without becoming part of the Cloud infrastructure, which allows them to reduce their IT investment cost and achieve optimal resource utilization. However, the migration of services to the Cloud increases the vulnerability to existing IT security threats and creates new ones that are intrinsic to the Cloud Computing architecture, thus the need for a thorough assessment of Cloud security risks during the process of service selection and deployment. Recently, the impact of effective management of service security satisfaction has been taken with greater seriousness by the Cloud Service Providers (CSP) and stakeholders. Nevertheless, the successful integration of the security element into the Cloud resource management operations does not only require methodical research, but also necessitates the meticulous modeling of the Cloud security requirements. To this end, we address throughout this thesis the challenges to security evaluation and integration in independent and interconnected Cloud Computing environments. We are interested in providing the Cloud consumers with a set of methods that allow them to optimize the security of their services and the CSPs with a set of strategies that enable them to provide security-aware Cloud-based service hosting. The originality of this thesis lies within two aspects: 1) the innovative description of the Cloud applications’ security requirements, which paved the way for an effective quantification and evaluation of the security of Cloud infrastructures; and 2) the design of rigorous mathematical models that integrate the security factor into the traditional problems of application deployment, resource provisioning, and workload management within current Cloud Computing infrastructures. The work in this thesis is carried out in three phases

Orchestrating datacenters and networks to facilitate the telecom cloud

In the Internet of services, information technology (IT) infrastructure providers play a critical role in making the services accessible to end-users. IT infrastructure providers host platforms and services in their datacenters (DCs). The cloud initiative has been accompanied by the introduction of new computing paradigms, such as Infrastructure as a Service (IaaS) and Software as a Service (SaaS), which have dramatically reduced the time and costs required to develop and deploy a service. However, transport networks become crucial to make services accessible to the user and to operate DCs. Transport networks are currently configured with big static fat pipes based on capacity over-provisioning aiming at guaranteeing traffic demand and other parameters committed in Service Level Agreement (SLA) contracts. Notwithstanding, such over-dimensioning adds high operational costs for DC operators and service providers. Therefore, new mechanisms to provide reconfiguration and adaptability of the transport network to reduce the amount of over-provisioned bandwidth are required. Although cloud-ready transport network architecture was introduced to handle the dynamic cloud and network interaction and Elastic Optical Networks (EONs) can facilitate elastic network operations, orchestration between the cloud and the interconnection network is eventually required to coordinate resources in both strata in a coherent manner. In addition, the explosion of Internet Protocol (IP)-based services requiring not only dynamic cloud and network interaction, but also additional service-specific SLA parameters and the expected benefits of Network Functions Virtualization (NFV), open the opportunity to telecom operators to exploit that cloud-ready transport network and their current infrastructure, to efficiently satisfy network requirements from the services. In the telecom cloud, a pay-per-use model can be offered to support services requiring resources from the transport network and its infrastructure. In this thesis, we study connectivity requirements from representative cloud-based services and explore connectivity models, architectures and orchestration schemes to satisfy them aiming at facilitating the telecom cloud. The main objective of this thesis is demonstrating, by means of analytical models and simulation, the viability of orchestrating DCs and networks to facilitate the telecom cloud. To achieve the main goal we first study the connectivity requirements for DC interconnection and services on a number of scenarios that require connectivity from the transport network. Specifically, we focus on studying DC federations, live-TV distribution, and 5G mobile networks. Next, we study different connectivity schemes, algorithms, and architectures aiming at satisfying those connectivity requirements. In particular, we study polling-based models for dynamic inter-DC connectivity and propose a novel notification-based connectivity scheme where inter-DC connectivity can be delegated to the network operator. Additionally, we explore virtual network topology provisioning models to support services that require service-specific SLA parameters on the telecom cloud. Finally, we focus on studying DC and network orchestration to fulfill simultaneously SLA contracts for a set of customers requiring connectivity from the transport network.En la Internet de los servicios, los proveedores de recursos relacionados con tecnologías de la información juegan un papel crítico haciéndolos accesibles a los usuarios como servicios. Dichos proveedores, hospedan plataformas y servicios en centros de datos. La oferta plataformas y servicios en la nube ha introducido nuevos paradigmas de computación tales como ofrecer la infraestructura como servicio, conocido como IaaS de sus siglas en inglés, y el software como servicio, SaaS. La disponibilidad de recursos en la nube, ha contribuido a la reducción de tiempos y costes para desarrollar y desplegar un servicio. Sin embargo, para permitir el acceso de los usuarios a los servicios así como para operar los centros de datos, las redes de transporte resultan imprescindibles. Actualmente, las redes de transporte están configuradas con conexiones estáticas y su capacidad sobredimensionada para garantizar la demanda de tráfico así como los distintos parámetros relacionados con el nivel de servicio acordado. No obstante, debido a que el exceso de capacidad en las conexiones se traduce en un elevado coste tanto para los operadores de los centros de datos como para los proveedores de servicios, son necesarios nuevos mecanismos que permitan adaptar y reconfigurar la red de forma eficiente de acuerdo a las nuevas necesidades de los servicios a los que dan soporte. A pesar de la introducción de arquitecturas que permiten la gestión de redes de transporte y su interacción con los servicios en la nube de forma dinámica, y de la irrupción de las redes ópticas elásticas, la orquestación entre la nube y la red es necesaria para coordinar de forma coherente los recursos en los distintos estratos. Además, la explosión de servicios basados el Protocolo de Internet, IP, que requieren tanto interacción dinámica con la red como parámetros particulares en los niveles de servicio además de los habituales, así como los beneficios que se esperan de la virtualización de funciones de red, representan una oportunidad para los operadores de red para explotar sus recursos y su infraestructura. La nube de operador permite ofrecer recursos del operador de red a los servicios, de forma similar a un sistema basado en pago por uso. En esta Tesis, se estudian requisitos de conectividad de servicios basados en la nube y se exploran modelos de conectividad, arquitecturas y modelos de orquestación que contribuyan a la realización de la nube de operador. El objetivo principal de esta Tesis es demostrar la viabilidad de la orquestación de centros de datos y redes para facilitar la nube de operador, mediante modelos analíticos y simulaciones. Con el fin de cumplir dicho objetivo, primero estudiamos los requisitos de conectividad para la interconexión de centros de datos y servicios en distintos escenarios que requieren conectividad en la red de transporte. En particular, nos centramos en el estudio de escenarios basados en federaciones de centros de datos, distribución de televisión en directo y la evolución de las redes móviles hacia 5G. A continuación, estudiamos distintos modelos de conectividad, algoritmos y arquitecturas para satisfacer los requisitos de conectividad. Estudiamos modelos de conectividad basados en sondeos para la interconexión de centros de datos y proponemos un modelo basado en notificaciones donde la gestión de la conectividad entre centros de datos se delega al operador de red. Estudiamos la provisión de redes virtuales para soportar en la nube de operador servicios que requieren parámetros específicos en los acuerdos de nivel de servicio además de los habituales. Finalmente, nos centramos en el estudio de la orquestación de centros de datos y redes con el objetivo de satisfacer de forma simultánea requisitos para distintos servicios.Postprint (published version

Facilitating self-adaptable inter-cloud management

Cloud Computing infrastructures have been developed as individual islands, and mostly proprietary solutions so far. However, as more and more infrastructure providers apply the technology, users face the inevitable question of using multiple infrastructures in parallel. Federated cloud management systems offer a simplified use of these infrastructures by hiding their proprietary solutions. As the infrastructure becomes more complex underneath these systems, the situations (like system failures, handling of load peaks and slopes) that users cannot easily handle, occur more and more frequently. Therefore, federations need to manage these situations autonomously without user interactions. This paper introduces a methodology to autonomously operate cloud federations by controlling their behavior with the help of knowledge management systems. Such systems do not only suggest reactive actions to comply with established Service Level Agreements (SLA) between provider and consumer, but they also find a balance between the fulfillment of established SLAs and resource consumption. The paper adopts rule-based techniques as its knowledge management solution and provides an extensible rule set for federated clouds built on top of multiple infrastructures. © 2012 IEEE