Resilience in Cloud Computing for Critical Systems. Resilience, Dependability, Reliability in the use of Cloud Computing in Critical Systems in Public Organizations.

La informática se está convirtiendo en la quinta utilidad (gas, agua, luz, teléfono) en parte debido al impacto de Cloud Computing en las mayorías de las organizaciones. Este uso de informática es usada por cada vez más tipos de sistemas, incluidos Sistemas Críticos. Esto tiene un impacto en la complejidad internad y la fiabilidad de los sistemas de la organización y los que se ofrecen a los clientes. Este trabajo investiga el uso de Cloud Computing por sistemas críticos, centrándose en las dependencias y especialmente en la fiabilidad de estos sistemas. Se han presentado algunos ejemplos de su uso, y aunque su utilización en sistemas críticos no está extendido, se presenta cual puede llegar a ser su impacto. El objetivo de este trabajo es primero definir un modelo que pueda representar de una forma cuantitativa las interdependencias en fiabilidad y interdependencia para las organizaciones que utilicen estos sistemas, y aplicar este modelo en un sistema crítico del campo de sanidad y mostrar sus resultados. Los conceptos de “macro-dependability” y “micro-dependability” son introducidos en el modelo para la definición de interdependencia y para analizar la fiabilidad de sistemas que dependen de otros sistemas. ABSTRACT With the increasing utilization of Internet services and cloud computing by most organizations (both private and public), it is clear that computing is becoming the 5th utility (along with water, electricity, telephony and gas). These technologies are used for almost all types of systems, and the number is increasing, including Critical Infrastructure systems. Even if Critical Infrastructure systems appear not to rely directly on cloud services, there may be hidden inter-dependencies. This is true even for private cloud computing, which seems more secure and reliable. The critical systems can began in some cases with a clear and simple design, but evolved as described by Egan to "rafted" networks. Because they are usually controlled by one or few organizations, even when they are complex systems, their dependencies can be understood. The organization oversees and manages changes. These CI systems have been affected by the introduction of new ICT models like global communications, PCs and the Internet. Even virtualization took more time to be adopted by Critical systems, due to their strategic nature, but once that these technologies have been proven in other areas, at the end they are adopted as well, for different reasons such as costs. A new technology model is happening now based on some previous technologies (virtualization, distributing and utility computing, web and software services) that are offered in new ways and is called cloud computing. The organizations are migrating more services to the cloud; this will have impact in their internal complexity and in the reliability of the systems they are offering to the organization itself and their clients. Not always this added complexity and associated risks to their reliability are seen. As well, when two or more CI systems are interacting, the risks of one can affect the rest, sharing the risks. This work investigates the use of cloud computing by critical systems, and is focused in the dependencies and reliability of these systems. Some examples are presented together with the associated risks. A framework is introduced for analysing the dependability and resilience of a system that relies on cloud services and how to improve them. As part of the framework, the concepts of micro and macro dependability are introduced to explain the internal and external dependability on services supplied by an external cloud. A pharmacovigilance model system has been used for framework validation.

Business model with discount incentive in a P2P-cloud multimedia streaming system

Today P2P faces two important challenges: design of mechanisms to encourage users' collaboration in multimedia live streaming services; design of reliable algorithms with QoS provision, to encourage the multimedia providers employ the P2P topology in commercial live streaming systems. We believe that these two challenges are tightly-related and there is much to be done with respect. This paper analyzes the effect of user behavior in a multi-tree P2P overlay and describes a business model based on monetary discount as incentive in a P2P-Cloud multimedia streaming system. We believe a discount model can boost up users' cooperation and loyalty and enhance the overall system integrity and performance. Moreover the model bounds the constraints for a provider's revenue and cost if the P2P system is leveraged on a cloud infrastructure. Our case study shows that a streaming system provider can establish or adapt his business model by applying the described bounds to achieve a good discount-revenue trade-off and promote the system to the users.

A multi-resource load balancing algorithm for cloud cache systems

With the advent of cloud computing model, distributed caches have become the cornerstone for building scalable applications. Popular systems like Facebook [1] or Twitter use Memcached [5], a highly scalable distributed object cache, to speed up applications by avoiding database accesses. Distributed object caches assign objects to cache instances based on a hashing function, and objects are not moved from a cache instance to another unless more instances are added to the cache and objects are redistributed. This may lead to situations where some cache instances are overloaded when some of the objects they store are frequently accessed, while other cache instances are less frequently used. In this paper we propose a multi-resource load balancing algorithm for distributed cache systems. The algorithm aims at balancing both CPU and Memory resources among cache instances by redistributing stored data. Considering the possible conflict of balancing multiple resources at the same time, we give CPU and Memory resources weighted priorities based on the runtime load distributions. A scarcer resource is given a higher weight than a less scarce resource when load balancing. The system imbalance degree is evaluated based on monitoring information, and the utility load of a node, a unit for resource consumption. Besides, since continuous rebalance of the system may affect the QoS of applications utilizing the cache system, our data selection policy ensures that each data migration minimizes the system imbalance degree and hence, the total reconfiguration cost can be minimized. An extensive simulation is conducted to compare our policy with other policies. Our policy shows a significant improvement in time efficiency and decrease in reconfiguration cost.

The University in the Cloud Computing.

With the advancement of Information and Communication Technology ICT which favors increasingly fast, easy, and accessible communication for all and which can reach large groups of people, there have been changes, in recent years in our society that have modified the way we interact, communicate and transmit information. Access to this, it is possible, not only through computers situated in a fixed location, but new mobile devices make it available, wherever the user happens to be located. Now, information "travels" with the user. These forms of communication, transmission and access to information, have also affected the way to conceive and manage business. To these new forms of business that the Internet has brought, is now added the concept of companies in the Cloud Computing ClC. The ClC technology is based on the supply and consumption of services on demand and pay per use, and it gives a 180 degree turn to the business management concept. Small and large businesses may use the latest developments in ICT, to manage their organizations without the need for expensive investments in them. This will enable enterprises to focus more specifically within the scope of their business, leaving the ICT control to the experts. We believe that education can also and should benefit from these new philosophies. ?Due to the global economic crisis in general and each country in particular, economic cutbacks have come to most universities. These are seen in the need to raise tuition rates, which makes increasingly fewer students have the opportunity to pursue higher education?. In this paper we propose using ClC technologies in universities and we make a dissertation on the advantages that it can provide to both: universities and students. For the universities, we expose two focuses, one: ?to reorganize university ICT structures with the ClC philosophy? and the other one, ?to extend the offer of the university education with education on demand?. Regarding the former we propose to use public or private Clouds, to reuse resources across the education community, to save costs on infrastructure investment, in upgrades and in maintenance of ICT, and paying only for what you use and with the ability to scale according to needs. Regarding the latter, we propose an educational model in the ClC, to increase the current university offerings, using educational units in the form of low-cost services and where students pay only for the units consumed on demand. For the students, they could study at any university in the world (virtually), from anywhere, without travel costs: money and time, and what is most important paying only for what they consume. We think that this proposal of education on demand may represent a great change in the current educational model, because strict registration deadlines disappear, and also the problem of economically disadvantaged students, who will not have to raise large amounts of money for an annual tuition. Also it will decrease the problem of loss of the money invested in an enrollment when the student dropout. In summary we think that this proposal is interesting for both, universities and students, we aim for "Higher education from anywhere, with access from any mobile device, at any time, without requiring large investments for students, and with reuse and optimization of resources by universities. Cost by consumption and consumption by service?. We argue for a Universal University "wisdom and knowledge accessible to all?

A scalable approach for content based image retrieval in cloud datacenter

The emergence of cloud datacenters enhances the capability of online data storage. Since massive data is stored in datacenters, it is necessary to effectively locate and access interest data in such a distributed system. However, traditional search techniques only allow users to search images over exact-match keywords through a centralized index. These techniques cannot satisfy the requirements of content based image retrieval (CBIR). In this paper, we propose a scalable image retrieval framework which can efficiently support content similarity search and semantic search in the distributed environment. Its key idea is to integrate image feature vectors into distributed hash tables (DHTs) by exploiting the property of locality sensitive hashing (LSH). Thus, images with similar content are most likely gathered into the same node without the knowledge of any global information. For searching semantically close images, the relevance feedback is adopted in our system to overcome the gap between low-level features and high-level features. We show that our approach yields high recall rate with good load balance and only requires a few number of hops.

GMonE: a complete approach to cloud monitoring

The inherent complexity of modern cloud infrastructures has created the need for innovative monitoring approaches, as state-of-the-art solutions used for other large-scale environments do not address specific cloud features. Although cloud monitoring is nowadays an active research field, a comprehensive study covering all its aspects has not been presented yet. This paper provides a deep insight into cloud monitoring. It proposes a unified cloud monitoring taxonomy, based on which it defines a layered cloud monitoring architecture. To illustrate it, we have implemented GMonE, a general-purpose cloud monitoring tool which covers all aspects of cloud monitoring by specifically addressing the needs of modern cloud infrastructures. Furthermore, we have evaluated the performance, scalability and overhead of GMonE with Yahoo Cloud Serving Benchmark (YCSB), by using the OpenNebula cloud middleware on the Grid’5000 experimental testbed. The results of this evaluation demonstrate the benefits of our approach, surpassing the monitoring performance and capabilities of cloud monitoring alternatives such as those present in state-of-the-art systems such as Amazon EC2 and OpenNebula.

Identifying Potential Risks and Benefits of Using Cloud in Distributed Software Development.

Cloud-based infrastructure has been increasingly adopted by the industry in distributed software development (DSD) environments. Its proponents claim that its several benefits include reduced cost, increased speed and greater productivity in software development. Empirical evaluations, however, are in the nascent stage of examining both the benefits and the risks of cloud-based infrastructure. The objective of this paper is to identify potential benefits and risks of using cloud in a DSD project conducted by teams based in Helsinki and Madrid. A cross-case qualitative analysis is performed based on focus groups conducted at the Helsinki and Madrid sites. Participants observations are used to supplement the analysis. The results of the analysis indicated that the main benefits of using cloud are rapid development, continuous integration, cost savings, code sharing, and faster ramp-up. The key risks determined by the project are dependencies, unavailability of access to the cloud, code commitment and integration, technical debt, and additional support costs. The results revealed that if such environments are not planned and set up carefully, the benefits of using cloud in DSD projects might be overshadowed by the risks associated with it.

Desarrollo de una plataforma de servicios gestionados para soluciones de contingencia en el Cloud

La proliferación en todo el mundo de las soluciones basadas en la nube hace que las empresas estén valorando mover su infraestructura o parte de ella a la nube, para así reducir los altos costes de inversión necesarios para mantener una infraestructura privada. Uno de los servicios que puede ser centralizado en la nube, mediante recursos compartidos entre varios clientes, son las soluciones de contingencia, como los servicios de protección de datos o los centros de recuperación ante desastres. Mediante este proyecto se pretende llevar a cabo el despliegue de una plataforma de servicios gestionados para ofrecer soluciones centralizadas, a clientes que lo requieran, de copias de seguridad y disaster recovery. Para la realización del proyecto se realizó un estudio de las tecnologías actuales para llevar a cabo la continuidad de negocio, los distintos tipos de backups, así como los tipos de replicación existente, local y remota. Posteriormente, se llevó a cabo un estudio de mercado para barajar las distintas posibilidades existentes para el despliegue de la infraestructura, siempre teniendo en cuenta el cliente objetivo. Finalmente, se realizó la fase de desarrollo, donde se detallan los componentes principales que componen la solución final, la localización de la infraestructura, un caso de uso, así como las principales ventajas de la solución. Se ha de destacar que se trata de un proyecto real, que se llevó a cabo en una empresa externa a la facultad, Omega Peripherals, donde una vez finalizado mi prácticum, se propuso dicho proyecto para desarrollarlo como continuación de mi labor en la empresa y formar parte de mi Trabajo Final de Grado (TFG). ---ABSTRACT---The worldwide proliferation of cloud-based solutions means that companies are evaluating their infrastructure or move part of it to the cloud, to reduce the high investment costs required to maintain a private infrastructure. One of the services that can be centralized in the cloud, through shared resources between multiple clients, are the solutions of contingency services as data protection or disaster recovery centers. This project aims to carry out the deployment of a managed services platform centralized solutions, to customers who need it, backup and disaster recovery services. The project consists of three phases. First, It was performed a study of the current business continuity technologies, the different types of backups, as well as replication types, local and remote. Second, it was performed a market study to shuffle the different possibilities for the deployment of infrastructure, keeping in mind the target customer. Finally, we found the development phase, where it details the main components that make up the final solution, the location of infrastructure, a use case, as well as the main advantages of the solution. It should be emphasized that this is a real project, which was carried out in an outside company to the university, called Omega Peripherals, where once I completed my practicum, it was proposed this project to develop it as a continuation of my job and develop it as my final dissertation.

Sistemas web con alta disponibilidad en cloud

Este trabajo contiene el estudio de las tecnologías que se están usando actualmente en web, tratando de explicar cuáles son sus principales componentes, su objetivo y funcionamiento. En base a un supuesto teórico de un montaje para un servicio web con un número muy alto de usuarios, y basándose en las tecnologías estudiadas, se propone un posible montaje completo de un sistema, que sería capaz de gestionar correctamente todas las peticiones, evitando fallos y tiempos de indisponibilidad. Se a~nade un análisis teórico de los costes deribados de la implantación del sistema, comparándolo con un sistema web convencional, y otro análisis con el funcionamiento de una caché y los benéficos, en carga, derivados de su uso.---ABSTRACT---This work contains a study about new web technologies. Its objective is to explain the web technologies componentes with their particular usage and performance. Based on a theorical postulation about a preparation of a web service with a large number of users, and working with the studied technologies, a complete system assembling is proposed. This system will be able to attend all the incoming requests, without failures nor downtimes. It is attached a theorical study of the derivative costs associated to the system implementation, compared to a traditional one. In addition, another study is included with the work ow of a cache and the benefits derived of its usage in work terms.

The educational learning lifecycle and the cloud computing

Currently, student dropout rates are a matter of concern among universities. Many research studies, aimed at discovering the causes, have been carried out. However, few solutions, that could serve all students and related problems, have been proposed so far. One such problem is caused by the lack of the "knowledge chain educational links" that occurs when students move onto higher studies without mastering their basic studies. Most regulated studies imparted at universities are designed so that some basic subjects serve as support for other, more complicated, subjects, thus forming a complicated knowledge network. When a link in this chain fails, student frustration occurs as it prevents him from fully understanding the following educational links. In this proposal we try to mitigate these disasters that stem, for the most part, the student?s frustration beyond his college stay. On one hand, we make a dissertation on the student?s learning process, which we divide into a series of phases that amount to what we call the "learning lifecycle." Also, we analyze at what stage the action by the stakeholders involved in this scenario: teachers and students; is most important. On the other hand, we consider that Information and Communication Technologies ICT, such as Cloud Computing, can help develop new ways, allowing for the teaching of higher education, while easing and facilitating the student?s learning process. But, methods and processes need to be defined as to direct the use of such technologies; in the teaching process in general, and within higher education in particular; in order to achieve optimum results. Our methodology integrates, as another actor, the ICT into the "Learning Lifecycle". We stimulate students to stop being merely spectators of their own education, and encourage them to take an active part in their training process. To do this, we offer a set of useful tools to determine not only academic failure causes, (for self assessment), but also to remedy these failures (with corrective actions); "discovered the causes it is easier to determine solutions?. We believe this study will be useful for both students and teachers. Students learn from their own experience and improve their learning process, while obtaining all of the "knowledge chain educational links? required in their studies. We stand by the motto "Studying to learn instead of studying to pass". Teachers will also be benefited by detecting where and how to strengthen their teaching proposals. All of this will also result in decreasing dropout rates.

Methodology for developing and application outsourcing in the cloud using SOA

New technologies such as, the new Information and Communication Technology ICT, break new paths and redefines the way we understand business, the Cloud Computing is one of them. The on demand resource gathering and the per usage payment scheme are now commonplace, and allows companies to save on their ICT investments. Despite the importance of this issue, we still lack methodologies that help companies, to develop applications oriented for its exploitation in the Cloud. In this study we aim to fill this gap and propose a methodology for the development of ICT applications, which are directed towards a business model, and further outsourcing in the Cloud. In the former the Development of SOA applications, we take, as a baseline scenario, a business model from which to obtain a business process model. To this end, we use software engineering tools; and in the latter The Outsourcing we propose a guide that would facilitate uploading business models into the Cloud; to this end we describe a SOA governance model, which controls the SOA. Additionally we propose a Cloud government that integrates Service Level Agreements SLAs, plus SOA governance, and Cloud architecture. Finally we apply our methodology in an example illustrating our proposal. We believe that our proposal can be used as a guide/pattern for the development of business applications.

Unified representation of monitoring information across federated cloud infrastructures

Nowadays one of the issues hindering the potential of federating cloud-based infrastructures to reach much larger scales is their standard management and monitoring. In particular, this is true in cases where these federated infrastructures provide emerging Future Internet and Smart Cities-oriented services, such as the Internet of Things (IoT), that benefit from cloud services. The contribution of this paper is the introduction of a unified monitoring architecture for federated cloud infrastructures accompanied by the adoption of a uniform representation of measurement data. The presented solution is capable of providing multi-domain compatibility, scalability, as well as the ability to analyze large amounts of monitoring data, collected from datacenters and offered through open and standardized APIs. The solution described herein has been deployed and is currently running on a community of 5 infrastructures within the framework of the European Project XIFI, to be extended to 12 more infrastructures.

Server power modeling for run-time energy optimization of cloud computing facilities

As advanced Cloud services are becoming mainstream, the contribution of data centers in the overall power consumption of modern cities is growing dramatically. The average consumption of a single data center is equivalent to the energy consumption of 25.000 households. Modeling the power consumption for these infrastructures is crucial to anticipate the effects of aggressive optimization policies, but accurate and fast power modeling is a complex challenge for high-end servers not yet satisfied by analytical approaches. This work proposes an automatic method, based on Multi-Objective Particle Swarm Optimization, for the identification of power models of enterprise servers in Cloud data centers. Our approach, as opposed to previous procedures, does not only consider the workload consolidation for deriving the power model, but also incorporates other non traditional factors like the static power consumption and its dependence with temperature. Our experimental results shows that we reach slightly better models than classical approaches, but simul- taneously simplifying the power model structure and thus the numbers of sensors needed, which is very promising for a short-term energy prediction. This work, validated with real Cloud applications, broadens the possibilities to derive efficient energy saving techniques for Cloud facilities.

A computational model of the anterior intraparietal area

The monkey anterior intraparietal area (AIP) encodes visual information about three-dimensional object shape that is used to shape the hand for grasping. In robotics a similar role has been played by modules that fit point cloud data to the superquadric family of shapes and its various extensions. We developed a model of shape tuning in AIP based on cosine tuning to superquadric parameters. However, the model did not fit the data well, and we also found that it was difficult to accurately reproduce these parameters using neural networks with the appropriate inputs (modelled on the caudal intraparietal area, CIP). The latter difficulty was related to the fact that there are large discontinuities in the superquadric parameters between very similar shapes. To address these limitations we adopted an alternative shape parameterization based on an Isomap nonlinear dimension reduction. The Isomap was built using gradients and curvatures of object surface depth. This alternative parameterization was low-dimensional (like superquadrics), but data-driven (similar to an alternative clustering approach that is also sometimes used in robotics) and lacked large discontinuities. Isomaps with 16 or more dimensions reproduced the AIP data fairly well. Moreover, we found that the Isomap parameters could be approximated from CIP-like input much more accurately than the superquadric parameters. We conclude that Isomaps, or perhaps alternative dimension reductions of CIP signals, provide a promising model of AIP tuning. We have now started to integrate our model with a robot hand, to explore the efficacy of Isomap shape reductions in grasp planning. Future work will consider dynamics of spike responses and integration with related visual and motor area models.

Project management in cloud

Este proyecto consiste en la construcción de un prototipo para la gestión de proyectos, destinada a usuarios del entorno profesional. La herramienta pretende servir de soporte a los equipos que realicen un proyecto dotando al usuario con la posibilidad de gestionar los tiempos del proyecto, gestión de requisitos, gestión de recursos, gestión de la documentación, etc. Adicionalmente, este trabajo llevará asociado un plan de negocio para poder estudiar la viabilidad del proyecto, en este plan de negocio se analizará; el entorno externo (competencia); análisis de las debilidades, fortalezas, amenazas y oportunidades; plan de marketing; plan económicofinanciero; análisis de riesgos del proyecto. A grandes rasgos, la herramienta desarrollada se compone de dos bases de datos (una relacional y otra no relacional), un conjunto de módulos que implementan la funcionalidad y una interfaz gráfica que proporciona a los usuarios una forma cómoda de interactuar con el sistema, principalmente ofrecerá las siguientes opciones:  Gestión de proyectos  Gestión de usuarios.  Gestión de recursos  Gestión de tiempos  Cuadro de mando y notificaciones. ---ABSTRACT---This Project consist of the construction of a prototype for Project management, intended for users of the profesional environment. The software aims to support teams conducting a project by providing the user with the ability to manage time, requirements management, resource management, document management, etc. In addition, this work includes a business plan to study the viability of the project. This business plan addresses the following; analysis of the external enviroment; analysis of the strengths, weaknesses, opportunities and threats; marketing plan; economic and financial plan; analysis of project risks. In general terms, the developed tools are composed of two databases (relational and nonrelational), a set of modules that implement the functionality and a web interface that gives users a convenient way to interact with the system. The options that the system offers are:  Project management  User management  Resource management  Time management  Dashboard and notifications