An anonymous reputation mechanism for cloud computing networks using volunteer resources

One of the major problems when using non-dedicated volunteer resources in adistributed network is the high volatility of these hosts since they can go offlineor become unavailable at any time without control. Furthermore, the use ofvolunteer resources implies some security issues due to the fact that they aregenerally anonymous entities which we know nothing about. So, how to trustin someone we do not know?.Over the last years an important number of reputation-based trust solutionshave been designed to evaluate the participants' behavior in a system.However, most of these solutions are addressed to P2P and ad-hoc mobilenetworks that may not fit well with other kinds of distributed systems thatcould take advantage of volunteer resources as recent cloud computinginfrastructures.In this paper we propose a first approach to design an anonymous reputationmechanism for CoDeS [1], a middleware for building fogs where deployingservices using volunteer resources. The participants are reputation clients(RC), a reputation authority (RA) and a certification authority (CA). Users needa valid public key certificate from the CA to register to the RA and obtain thedata needed to participate into the system, as now an opaque identifier thatwe call here pseudonym and an initial reputation value that users provide toother users when interacting together. The mechanism prevents not only themanipulation of the provided reputation values but also any disclosure of theusers' identities to any other users or authorities so the anonymity isguaranteed.

Tecnologies de cloud computing Openstack/StackOps

El propòsit d'aquest TFC és investigar i fer una instal·lació des de zero d'un model de negoci basat en l'allotjament web fent servir tecnologies de Cloud Computing. El software open-source que es farà servir per aquesta finalitat serà Openstack el qual es basa en un model de servei com infraestructura (IaaS). La nostra finalitat és poder implementar el model IaaS basat en Openstack. Per duu a terme aquest desplegament es farà servir dos hipervisors (KVM i VMware ESXi) per tal de testejar diferents sistemes d¿hipervisors treballant conjuntament.

Virtualización y cloud computing en la PYME

El presente documento introduce a las pequeñas y medianas empresas en el mundo de la virtualización y el cloud computing. Partiendo de la presentación de ambas tecnologías, se recorren las diferentes fases por las que atraviesa un proyecto tecnológico consistente en la instalación de una plataforma virtualizada que alberga los sistemas informáticos básicos en una PYME.

Measuring effective electroweak couplings in single top production at the CERN LHC

s out to be more relevant than naively expected, is retained. Finally we analyze different aspects of the total cross section relevant to the measurement of new physics through the effective couplings. The above analysis also applies to top antiquark production in a straightforward way.

Video transcoding in a distributed cloud computing environment

Video transcoding refers to the process of converting a digital video from one format into another format. It is a compute-intensive operation. Therefore, transcoding of a large number of simultaneous video streams requires a large amount of computing resources. Moreover, to handle di erent load conditions in a cost-e cient manner, the video transcoding service should be dynamically scalable. Infrastructure as a Service Clouds currently offer computing resources, such as virtual machines, under the pay-per-use business model. Thus the IaaS Clouds can be leveraged to provide a coste cient, dynamically scalable video transcoding service. To use computing resources e ciently in a cloud computing environment, cost-e cient virtual machine provisioning is required to avoid overutilization and under-utilization of virtual machines. This thesis presents proactive virtual machine resource allocation and de-allocation algorithms for video transcoding in cloud computing. Since users' requests for videos may change at di erent times, a check is required to see if the current computing resources are adequate for the video requests. Therefore, the work on admission control is also provided. In addition to admission control, temporal resolution reduction is used to avoid jitters in a video. Furthermore, in a cloud computing environment such as Amazon EC2, the computing resources are more expensive as compared with the storage resources. Therefore, to avoid repetition of transcoding operations, a transcoded video needs to be stored for a certain time. To store all videos for the same amount of time is also not cost-e cient because popular transcoded videos have high access rate while unpopular transcoded videos are rarely accessed. This thesis provides a cost-e cient computation and storage trade-o strategy, which stores videos in the video repository as long as it is cost-e cient to store them. This thesis also proposes video segmentation strategies for bit rate reduction and spatial resolution reduction video transcoding. The evaluation of proposed strategies is performed using a message passing interface based video transcoder, which uses a coarse-grain parallel processing approach where video is segmented at group of pictures level.

Development of agnostic mobile applications with cross-platform cloud computing platforms

Smart phones became part and parcel of our life, where mobility provides a freedom of not being bounded by time and space. In addition, number of smartphones produced each year is skyrocketing. However, this also created discrepancies or fragmentation among devices and OSes, which in turn made an exceeding hard for developers to deliver hundreds of similar featured applications with various versions for the market consumption. This thesis is an attempt to investigate whether cloud based mobile development platforms can mitigate and eventually eliminate fragmentation challenges. During this research, we have selected and analyzed the most popular cloud based development platforms and tested integrated cloud features. This research showed that cloud based mobile development platforms may able to reduce mobile fragmentation and enable to utilize single codebase to deliver a mobile application for different platforms.

Estudio de los beneficios de la implementación del modelo de gestión cloud computing en comparación al modelo de gestión tradicional. Caso de estudio: Corporación ADC-HAS Management Ecuador S.A.

El desarrollo eficiente y oportuno de las actividades propias de las empresas exige una constante renovación en su infraestructura, capacitación permanente de su staff, investigar nuevas tecnológicas y la asignación cada vez mayor del presupuesto para su área de TIC. Varios modelos de gestión han intentado suplir estas necesidades, entre los que se puede mencionar a: hosting, outsourcing, leasing, servicios profesionales, asesorías especializadas, entre otros. El modelo de gestión cloud computing y sus diversas opciones se está posicionando últimamente como la solución más viable y rápida de implementar. De ahí que, este proyecto se enfoca en el estudio de este modelo como una alternativa al modelo de gestión tradicional de servicios TIC, y toma como referencia para el desarrollo de esta tesis la situación actual de la infraestructura tecnológica de la Corporación ADC&HAS Management Ecuador S.A. No se pretende justificar al cloud como una solución definitiva, sino plantear este modelo como una alternativa útil a la realidad tecnológica de la Corporación, y en base a sus propiedades concluir que fue el modelo que mejor se ajustó a la estrategia institucional en términos: organizacionales, tecnológicos y financieros, por lo menos para los próximos cinco años. En los dos primeros capítulos se referencian algunos elementos conceptuales en los que se fundamenta las TIC y se mencionan ciertos parámetros que intervinieron en su evolución. El tercer capítulo describe a la Corporación; y en el capítulo cuarto se aplican los conceptos de los primeros capítulos reforzados con las experiencias publicadas en la revista Computerworld (2010 hasta la presente) y que permitieron evaluar los beneficios de los dos modelos de gestión y las razones para implementarlos o mantenerlos.

Análisis del modelo de negocio del cloud computing. Caso: empresa de desarrollo DevTeam

Hoy en día el uso de las TIC en una empresa se ha convertido en indispensable sin importar su tamaño o industria a tal punto que ya no es una ventaja competitiva el simple hecho de usarla sino que la clave es determinar cuál es la mejor para la empresa. Existen en el mercado servicios en-línea que igualan o sobrepasan los estándares de tecnologías pagadas que incluso deben ser instaladas dentro de la empresa consumiendo recursos y en algunos casos subutilizándolos, los servicios del cloud computing poseen la flexibilidad y capacidad que la empresa requiere de acuerdo a sus necesidades de crecimiento y de cambio continuo que el mercado exige en la actualidad. Algunas empresas no invierten en dichas tecnologías porque no saben que pueden accederlas a costos bajos e incluso en algunos casos sin pagar un solo centavo y pierden competitividad y productividad por simple desconocimiento. El uso de servicios SaaS e IaaS afecta al flujo de caja de manera positiva comparada con una inversión en infraestructura propia, sobre todo en empresas que están empezando a funcionar o en aquellas que están en proceso de renovación tecnológica. Después de realizada esta investigación se recomienda el uso de los servicios de cloud computing, pero es evidente que no son útiles para todas las empresas y la utilidad depende de la criticidad de las aplicaciones o infraestructuras, el momento por el que pasa la compañía, tamaño de la empresa, ¿Cloud pública o Cloud privada?, en ocasiones, virtualizar también es racionalizar y la visión integral de la seguridad. Por otro lado, después de tabular los datos obtenidos en la encuesta número 2 se evidenció que el lanzamiento del Servicio en la nube de EcuFlow incrementó la demanda de esta herramienta en el mercado.

Collaborative grid infrastructure for molecular simulations: The eMinerals minigrid as a prototype integrated computer and data grid

This paper describes a prototype grid infrastructure, called the eMinerals minigrid, for molecular simulation scientists. which is based on an integration of shared compute and data resources. We describe the key components, namely the use of Condor pools, Linux/Unix clusters with PBS and IBM's LoadLeveller job handling tools, the use of Globus for security handling, the use of Condor-G tools for wrapping globus job submit commands, Condor's DAGman tool for handling workflow, the Storage Resource Broker for handling data, and the CCLRC dataportal and associated tools for both archiving data with metadata and making data available to other workers.

Major differences of cloud computing adoption in universities: Europe vs. Middle East

The extensive use of cloud computing in educational institutes around the world brings unique challenges for universities. Some of these challenges are due to clear differences between Europe and Middle East universities. These differences stem from the natural variation between people. Cloud computing has created a new concept to deal with software services and hardware infrastructure. Some benefits are immediately gained, for instance, to allow students to share their information easily and to discover new experiences of the education system. However, this introduces more challenges, such as security and configuration of resources in shared environments. Educational institutes cannot escape from these challenges. Yet some differences occur between universities which use cloud computing as an educational tool or a form of social connection. This paper discusses some benefits and limitations of using cloud computing and major differences in using cloud computing at universities in Europe and the Middle East, based on the social perspective, security and economics concepts, and personal responsibility.