Web Services Workflows—Composition, Co-Ordination, and Transactions in Service-Oriented Computing

Web services can be seen as a newly emerging research area for Service-oriented Computing and their implementation in Service-oriented Architectures. Web services are self-contained, self-describing modular applications or components providing services. Web services may be dynamically aggregated, composed, and enacted as Web services Workflows. This requires frameworks and interaction protocols for their co-ordination and transaction support. In a Service-oriented Computing setting, transactions are more complex, involve multiple parties (roles), span many organizations, and may be long-running, consisting of a highly decentralized service partner and performed by autonomous entities. A Service-oriented Transaction Model has to provide comprehensive support for long-running propositions including negotiations, conversations, commitments, contracts, tracking, payments, and exception handling. Current transaction models and mechanisms including their protocols and primitives do not sufficiently cater for quality-aware and long running transactions comprising loosely-coupled (federated) service partners and resources. Web services transactions require co-ordination behavior provided by a traditional transaction mechanism to control the operations and outcome of an application. Furthermore, Web services transactions require the capability to handle the co-ordination of processing outcomes or results from multiple services in a more flexible manner. This requires more relaxed forms of transactions—those that do not strictly have to abide by the ACID properties—such as loosely-coupled collaboration and workflows. Furthermore, there is a need to group Web services into applications that require some form of correlation, but do not necessarily require transactional behavior. The purpose of this paper is to provide a state-of-the-art review and overview of some proposed standards surrounding Web services composition, co-ordination, and transaction. In particular the Business Process Execution Language for Web services (BPEL4WS), its co-ordination, and transaction frameworks (WS-Co-ordination and WS-Transaction) are discussed.

Acceso a catálogo de biblioteca desde móviles Android y navegadores mediante servicios web

Este PFC trata la construcción de un sistema de acceso al catálogo de una biblioteca doméstica a través de distintas interfaces de usuario que hacen uso de unos mismos servicios web REST expuestos en un servidor Java EE. Su desarrollo implica la integración de múltiples tecnologías open source a varios niveles.

Resource Management for Responsive Web Computing

The exploding demand for services like the World Wide Web reflects the potential that is presented by globally distributed information systems. The number of WWW servers world-wide has doubled every 3 to 5 months since 1993, outstripping even the growth of the Internet. At each of these self-managed sites, the Common Gateway Interface (CGI) and Hypertext Transfer Protocol (HTTP) already constitute a rudimentary basis for contributing local resources to remote collaborations. However, the Web has serious deficiencies that make it unsuited for use as a true medium for metacomputing --- the process of bringing hardware, software, and expertise from many geographically dispersed sources to bear on large scale problems. These deficiencies are, paradoxically, the direct result of the very simple design principles that enabled its exponential growth. There are many symptoms of the problems exhibited by the Web: disk and network resources are consumed extravagantly; information search and discovery are difficult; protocols are aimed at data movement rather than task migration, and ignore the potential for distributing computation. However, all of these can be seen as aspects of a single problem: as a distributed system for metacomputing, the Web offers unpredictable performance and unreliable results. The goal of our project is to use the Web as a medium (within either the global Internet or an enterprise intranet) for metacomputing in a reliable way with performance guarantees. We attack this problem one four levels: (1) Resource Management Services: Globally distributed computing allows novel approaches to the old problems of performance guarantees and reliability. Our first set of ideas involve setting up a family of real-time resource management models organized by the Web Computing Framework with a standard Resource Management Interface (RMI), a Resource Registry, a Task Registry, and resource management protocols to allow resource needs and availability information be collected and disseminated so that a family of algorithms with varying computational precision and accuracy of representations can be chosen to meet realtime and reliability constraints. (2) Middleware Services: Complementary to techniques for allocating and scheduling available resources to serve application needs under realtime and reliability constraints, the second set of ideas aim at reduce communication latency, traffic congestion, server work load, etc. We develop customizable middleware services to exploit application characteristics in traffic analysis to drive new server/browser design strategies (e.g., exploit self-similarity of Web traffic), derive document access patterns via multiserver cooperation, and use them in speculative prefetching, document caching, and aggressive replication to reduce server load and bandwidth requirements. (3) Communication Infrastructure: Finally, to achieve any guarantee of quality of service or performance, one must get at the network layer that can provide the basic guarantees of bandwidth, latency, and reliability. Therefore, the third area is a set of new techniques in network service and protocol designs. (4) Object-Oriented Web Computing Framework A useful resource management system must deal with job priority, fault-tolerance, quality of service, complex resources such as ATM channels, probabilistic models, etc., and models must be tailored to represent the best tradeoff for a particular setting. This requires a family of models, organized within an object-oriented framework, because no one-size-fits-all approach is appropriate. This presents a software engineering challenge requiring integration of solutions at all levels: algorithms, models, protocols, and profiling and monitoring tools. The framework captures the abstract class interfaces of the collection of cooperating components, but allows the concretization of each component to be driven by the requirements of a specific approach and environment.

Android as a cloud ticket validator

Trabalho Final de Mestrado para a obtenção do grau de Mestre em Engenharia Informática e de Computadores

An Animating Spark: Mundane Computing and the Web of Data

Network connectivity is reaching more and more into the physical world. This is potentially transformative – allowing every object and service in the world to talk to one other—and to their users—through any networked interface; where online services are the connective tissue of the physical world and where physical objects are avatars of online services.

Progettazione e Sviluppo di Applicazioni Web per Cloud Computing

Negli ultimi anni si sente sempre più spesso parlare di cloud computing. L'idea di fondo di questo concetto è quella di pagare per il solo effettivo utilizzo di un servizio, disponibile sulla rete, avendo a disposizione la possibilità di poter variare le proprie risorse utilizzabili a seconda delle necessità, che potrebbero essere, per esempio, applicazioni standard oppure spazi di storage per i dati. Quando cominciò a diffondersi l'utilizzo del Web, la rete Internet veniva raffigurata come una nuvola (cloud) in modo tale che si rendesse l'idea di un'entità esterna rispetto alla nostra casa o al nostro posto di lavoro, un qualcosa cioè al di fuori dei luoghi abituali in cui vengono utilizzati i PC. Tale rappresentazione diventa ora utile per poter spiegare il concetto di cloud computing. Infatti, grazie a questa nuova tecnologia, dati e programmi normalmente presenti nei nostri computer potranno ora trovarsi sul cloud. Molti reparti IT sono costretti a dedicare una parte significativa del loro tempo a progetti di implementazione, manutenzione e upgrade che spesso non danno un vero valore per l'azienda. I team di sviluppo hanno cominciato quindi a rivolgersi a questa nuova tecnologia emergente per poter minimizzare il tempo dedicato ad attività a basso valore aggiunto per potersi concentrare su quelle attività strategiche che possono fare la differenza per un'azienda. Infatti un'infrastruttura come quella cloud computing promette risparmi nei costi amministrativi che raggiungono addirittura il 50% rispetto ad un software standard di tipo client/server. Questa nuova tecnologia sta dando inizio ad un cambiamento epocale nel mondo dello sviluppo delle applicazioni. Il passaggio che si sta effettuando verso le nuove soluzioni cloud computing consente infatti di creare applicazioni solide in tempi decisamente più brevi e con costi assai inferiori, evitando inoltre tutte le seccature associate a server, soluzioni software singole, aggiornamenti, senza contare il personale necessario a gestire tutto questo. L'obiettivo di questa tesi è quello di mostrare una panoramica della progettazione e dello sviluppo di applicazioni Web nel cloud computing, analizzandone pregi e difetti in relazione alle soluzioni software attuali. Nel primo capitolo viene mostrato un quadro generale in riferimento al cloud, mettendo in luce le sue caratteristiche fondamentali, esaminando la sua architettura e valutando vantaggi e svantaggi di tale piattaforma. Nel secondo capitolo viene presentata la nuova metodologia di progettazione nel cloud, operando prima di tutto un confronto con lo sviluppo dei software standard e analizzando poi l'impatto che il cloud computing opera sulla progettazione. Nel terzo capitolo si entra nel merito della progettazione e sviluppo di applicazioni SaaS, specificandone le caratteristiche comuni ed elencando le piattaforme di rilievo allo stato dell'arte. Si entrerà inoltre nel merito della piattaforma Windows Azure. Nel quarto capitolo viene analizzato nel particolare lo sviluppo di applicazioni SaaS Multi-Tenant, specificando livelli e caratteristiche, fino a spiegare le architetture metadata-driven. Nel quinto capitolo viene operato un confronto tra due possibili approcci di sviluppo di un software cloud, analizzando nello specifico le loro differenze a livello di requisiti non funzionali. Nel sesto capitolo, infine, viene effettuata una panoramica dei costi di progettazione di un'applicazione cloud.

Prototipo di schermo adattativo basato su Android e Bluetooth Low Energy

La tesi nasce da un'attività di ricerca approfondita su alcune tecnologie innovative e all'avanguardia nell'ambito del mobile computing e dell'Internet of Things. Tra queste il focus principale è orientato allo studio del Bluetooth Low Energy, nuova specifica di Bluetooth caratterizzata principalmente da un consumo di energia assai ridotto. In particolare, si è approfondito il suo funzionamento nel caso dei beacon, piccoli dispositivi che permettono una localizzazione mediante l'invio di un segnale BLE. Inoltre è stata analizzata la possibilità di interazione con Android, poiché oggigiorno non si può evitare di pensare a come queste tecnologie possano interfacciarsi con il mondo degli smartphone e dei tablet. Come conseguenza di tale attività di ricerca è stato analizzato un caso di studio che permettesse di applicare le tecnologie studiate e la loro interazione. Si è pensato quindi a un piccolo sistema distribuito per schermi adattativi (capaci di modificare i contenuti visualizzati in relazione ad eventi esterni) affinché ogni schermo mostrasse dinamicamente l'orario delle lezioni di ciascuno studente all'avvicinarsi di quest'ultimo, e solo per il tempo di permanenza nei pressi dello schermo. Si è quindi progettato e sviluppato un prototipo, e infine durante il testing si sono potute verificare le attuali potenzialità di queste tecnologie e trarre conclusioni sulla possibilità della loro futura diffusione e di impiego in contesti differenti.

Sistema Bluetooth-based di remarketing pervasivo

Il progetto si propone di dotare la realta fisica di un estensione digitale. Sensori, attuatori e tecnologie embedded hanno cambiato il nostro modo di lavorare, allenarci e seguire i nostri interessi. Il mondo del commercio non e rimasto a guardare ed ha dovuto adattarsi alla metamorfosi high-tech del settore dei servizi. Il sistema proposto costituisce un promotore per acquisti ed un raccoglitore intelligente di abitudini sullo shopping e si compone di applicazione mobile, microcontroller e web server. Caratteristica prima e principale del progetto e sicuramente la pervasivita. All'utente ed utilizzatore dell'app dello shopping center deve essere certamente resa nota la collaborazione al fine di raccogliere dati statistici sulle sue abitudini, tuttavia sono le modalita di tale operazione a dover rimanere velate, in modo da non appesantire il cliente con tediose operazioni di invio di feedback e valutazioni ed allo stesso tempo permettere una raccolta capillare delle informazioni. Parallelamente alla raccolta di dati funzionali al producer, sono state implementate features per il consumatore, come notifiche promozionali place-triggered e pubblicita mirata. Tra tutte le tecnologie adibite allo scambio di informazioni, si e scelto l'utilizzo del Bluetooth e del piu recente Bluetooth Low Energy (BLE) per permettere ai dispositivi di comunicare tra loro.

A Case for CDN-as-a-Service in the Cloud: A Mobile Cloud Networking Argument

Content Distribution Networks are mandatory components of modern web architectures, with plenty of vendors offering their services. Despite its maturity, new paradigms and architecture models are still being developed in this area. Cloud Computing, on the other hand, is a more recent concept which has expanded extremely quickly, with new services being regularly added to cloud management software suites such as OpenStack. The main contribution of this paper is the architecture and the development of an open source CDN that can be provisioned in an on-demand, pay-as-you-go model thereby enabling the CDN as a Service paradigm. We describe our experience with integration of CDNaaS framework in a cloud environment, as a service for enterprise users. We emphasize the flexibility and elasticity of such a model, with each CDN instance being delivered on-demand and associated to personalized caching policies as well as an optimized choice of Points of Presence based on exact requirements of an enterprise customer. Our development is based on the framework developed in the Mobile Cloud Networking EU FP7 project, which offers its enterprise users a common framework to instantiate and control services. CDNaaS is one of the core support components in this project as is tasked to deliver different type of multimedia content to several thousands of users geographically distributed. It integrates seamlessly in the MCN service life-cycle and as such enjoys all benefits of a common design environment, allowing for an improved interoperability with the rest of the services within the MCN ecosystem.

Semantic Service Discovery Techniques for the composable web

This PhD thesis contributes to the problem of resource and service discovery in the context of the composable web. In the current web, mashup technologies allow developers reusing services and contents to build new web applications. However, developers face a problem of information flood when searching for appropriate services or resources for their combination. To contribute to overcoming this problem, a framework is defined for the discovery of services and resources. In this framework, three levels are defined for performing discovery at content, discovery and agente levels. The content level involves the information available in web resources. The web follows the Representational Stateless Transfer (REST) architectural style, in which resources are returned as representations from servers to clients. These representations usually employ the HyperText Markup Language (HTML), which, along with Content Style Sheets (CSS), describes the markup employed to render representations in a web browser. Although the use of SemanticWeb standards such as Resource Description Framework (RDF) make this architecture suitable for automatic processes to use the information present in web resources, these standards are too often not employed, so automation must rely on processing HTML. This process, often referred as Screen Scraping in the literature, is the content discovery according to the proposed framework. At this level, discovery rules indicate how the different pieces of data in resources’ representations are mapped onto semantic entities. By processing discovery rules on web resources, semantically described contents can be obtained out of them. The service level involves the operations that can be performed on the web. The current web allows users to perform different tasks such as search, blogging, e-commerce, or social networking. To describe the possible services in RESTful architectures, a high-level feature-oriented service methodology is proposed at this level. This lightweight description framework allows defining service discovery rules to identify operations in interactions with REST resources. The discovery is thus performed by applying discovery rules to contents discovered in REST interactions, in a novel process called service probing. Also, service discovery can be performed by modelling services as contents, i.e., by retrieving Application Programming Interface (API) documentation and API listings in service registries such as ProgrammableWeb. For this, a unified model for composable components in Mashup-Driven Development (MDD) has been defined after the analysis of service repositories from the web. The agent level involves the orchestration of the discovery of services and contents. At this level, agent rules allow to specify behaviours for crawling and executing services, which results in the fulfilment of a high-level goal. Agent rules are plans that allow introspecting the discovered data and services from the web and the knowledge present in service and content discovery rules to anticipate the contents and services to be found on specific resources from the web. By the definition of plans, an agent can be configured to target specific resources. The discovery framework has been evaluated on different scenarios, each one covering different levels of the framework. Contenidos a la Carta project deals with the mashing-up of news from electronic newspapers, and the framework was used for the discovery and extraction of pieces of news from the web. Similarly, in Resulta and VulneraNET projects the discovery of ideas and security knowledge in the web is covered, respectively. The service level is covered in the OMELETTE project, where mashup components such as services and widgets are discovered from component repositories from the web. The agent level is applied to the crawling of services and news in these scenarios, highlighting how the semantic description of rules and extracted data can provide complex behaviours and orchestrations of tasks in the web. The main contributions of the thesis are the unified framework for discovery, which allows configuring agents to perform automated tasks. Also, a scraping ontology has been defined for the construction of mappings for scraping web resources. A novel first-order logic rule induction algorithm is defined for the automated construction and maintenance of these mappings out of the visual information in web resources. Additionally, a common unified model for the discovery of services is defined, which allows sharing service descriptions. Future work comprises the further extension of service probing, resource ranking, the extension of the Scraping Ontology, extensions of the agent model, and contructing a base of discovery rules. Resumen La presente tesis doctoral contribuye al problema de descubrimiento de servicios y recursos en el contexto de la web combinable. En la web actual, las tecnologías de combinación de aplicaciones permiten a los desarrolladores reutilizar servicios y contenidos para construir nuevas aplicaciones web. Pese a todo, los desarrolladores afrontan un problema de saturación de información a la hora de buscar servicios o recursos apropiados para su combinación. Para contribuir a la solución de este problema, se propone un marco de trabajo para el descubrimiento de servicios y recursos. En este marco, se definen tres capas sobre las que se realiza descubrimiento a nivel de contenido, servicio y agente. El nivel de contenido involucra a la información disponible en recursos web. La web sigue el estilo arquitectónico Representational Stateless Transfer (REST), en el que los recursos son devueltos como representaciones por parte de los servidores a los clientes. Estas representaciones normalmente emplean el lenguaje de marcado HyperText Markup Language (HTML), que, unido al estándar Content Style Sheets (CSS), describe el marcado empleado para mostrar representaciones en un navegador web. Aunque el uso de estándares de la web semántica como Resource Description Framework (RDF) hace apta esta arquitectura para su uso por procesos automatizados, estos estándares no son empleados en muchas ocasiones, por lo que cualquier automatización debe basarse en el procesado del marcado HTML. Este proceso, normalmente conocido como Screen Scraping en la literatura, es el descubrimiento de contenidos en el marco de trabajo propuesto. En este nivel, un conjunto de reglas de descubrimiento indican cómo los diferentes datos en las representaciones de recursos se corresponden con entidades semánticas. Al procesar estas reglas sobre recursos web, pueden obtenerse contenidos descritos semánticamente. El nivel de servicio involucra las operaciones que pueden ser llevadas a cabo en la web. Actualmente, los usuarios de la web pueden realizar diversas tareas como búsqueda, blogging, comercio electrónico o redes sociales. Para describir los posibles servicios en arquitecturas REST, se propone en este nivel una metodología de alto nivel para descubrimiento de servicios orientada a funcionalidades. Este marco de descubrimiento ligero permite definir reglas de descubrimiento de servicios para identificar operaciones en interacciones con recursos REST. Este descubrimiento es por tanto llevado a cabo al aplicar las reglas de descubrimiento sobre contenidos descubiertos en interacciones REST, en un nuevo procedimiento llamado sondeo de servicios. Además, el descubrimiento de servicios puede ser llevado a cabo mediante el modelado de servicios como contenidos. Es decir, mediante la recuperación de documentación de Application Programming Interfaces (APIs) y listas de APIs en registros de servicios como ProgrammableWeb. Para ello, se ha definido un modelo unificado de componentes combinables para Mashup-Driven Development (MDD) tras el análisis de repositorios de servicios de la web. El nivel de agente involucra la orquestación del descubrimiento de servicios y contenidos. En este nivel, las reglas de nivel de agente permiten especificar comportamientos para el rastreo y ejecución de servicios, lo que permite la consecución de metas de mayor nivel. Las reglas de los agentes son planes que permiten la introspección sobre los datos y servicios descubiertos, así como sobre el conocimiento presente en las reglas de descubrimiento de servicios y contenidos para anticipar contenidos y servicios por encontrar en recursos específicos de la web. Mediante la definición de planes, un agente puede ser configurado para descubrir recursos específicos. El marco de descubrimiento ha sido evaluado sobre diferentes escenarios, cada uno cubriendo distintos niveles del marco. El proyecto Contenidos a la Carta trata de la combinación de noticias de periódicos digitales, y en él el framework se ha empleado para el descubrimiento y extracción de noticias de la web. De manera análoga, en los proyectos Resulta y VulneraNET se ha llevado a cabo un descubrimiento de ideas y de conocimientos de seguridad, respectivamente. El nivel de servicio se cubre en el proyecto OMELETTE, en el que componentes combinables como servicios y widgets se descubren en repositorios de componentes de la web. El nivel de agente se aplica al rastreo de servicios y noticias en estos escenarios, mostrando cómo la descripción semántica de reglas y datos extraídos permiten proporcionar comportamientos complejos y orquestaciones de tareas en la web. Las principales contribuciones de la tesis son el marco de trabajo unificado para descubrimiento, que permite configurar agentes para realizar tareas automatizadas. Además, una ontología de extracción ha sido definida para la construcción de correspondencias y extraer información de recursos web. Asimismo, un algoritmo para la inducción de reglas de lógica de primer orden se ha definido para la construcción y el mantenimiento de estas correspondencias a partir de la información visual de recursos web. Adicionalmente, se ha definido un modelo común y unificado para el descubrimiento de servicios que permite la compartición de descripciones de servicios. Como trabajos futuros se considera la extensión del sondeo de servicios, clasificación de recursos, extensión de la ontología de extracción y la construcción de una base de reglas de descubrimiento.

Contribution to multiuser videoconferencing systems based on cloud computing

Multi-user videoconferencing systems offer communication between more than two users, who are able to interact through their webcams, microphones and other components. The use of these systems has been increased recently due to, on the one hand, improvements in Internet access, networks of companies, universities and houses, whose available bandwidth has been increased whilst the delay in sending and receiving packets has decreased. On the other hand, the advent of Rich Internet Applications (RIA) means that a large part of web application logic and control has started to be implemented on the web browsers. This has allowed developers to create web applications with a level of complexity comparable to traditional desktop applications, running on top of the Operating Systems. More recently the use of Cloud Computing systems has improved application scalability and involves a reduction in the price of backend systems. This offers the possibility of implementing web services on the Internet with no need to spend a lot of money when deploying infrastructures and resources, both hardware and software. Nevertheless there are not many initiatives that aim to implement videoconferencing systems taking advantage of Cloud systems. This dissertation proposes a set of techniques, interfaces and algorithms for the implementation of videoconferencing systems in public and private Cloud Computing infrastructures. The mechanisms proposed here are based on the implementation of a basic videoconferencing system that runs on the web browser without any previous installation requirements. To this end, the development of this thesis starts from a RIA application with current technologies that allow users to access their webcams and microphones from the browser, and to send captured data through their Internet connections. Furthermore interfaces have been implemented to allow end users to participate in videoconferencing rooms that are managed in different Cloud provider servers. To do so this dissertation starts from the results obtained from the previous techniques and backend resources were implemented in the Cloud. A traditional videoconferencing service which was implemented in the department was modified to meet typical Cloud Computing infrastructure requirements. This allowed us to validate whether Cloud Computing public infrastructures are suitable for the traffic generated by this kind of system. This analysis focused on the network level and processing capacity and stability of the Cloud Computing systems. In order to improve this validation several other general considerations were taken in order to cover more cases, such as multimedia data processing in the Cloud, as research activity has increased in this area in recent years. The last stage of this dissertation is the design of a new methodology to implement these kinds of applications in hybrid clouds reducing the cost of videoconferencing systems. Finally, this dissertation opens up a discussion about the conclusions obtained throughout this study, resulting in useful information from the different stages of the implementation of videoconferencing systems in Cloud Computing systems. RESUMEN Los sistemas de videoconferencia multiusuario permiten la comunicación entre más de dos usuarios que pueden interactuar a través de cámaras de video, micrófonos y otros elementos. En los últimos años el uso de estos sistemas se ha visto incrementado gracias, por un lado, a la mejora de las redes de acceso en las conexiones a Internet en empresas, universidades y viviendas, que han visto un aumento del ancho de banda disponible en dichas conexiones y una disminución en el retardo experimentado por los datos enviados y recibidos. Por otro lado también ayudó la aparación de las Aplicaciones Ricas de Internet (RIA) con las que gran parte de la lógica y del control de las aplicaciones web comenzó a ejecutarse en los mismos navegadores. Esto permitió a los desarrolladores la creación de aplicaciones web cuya complejidad podía compararse con la de las tradicionales aplicaciones de escritorio, ejecutadas directamente por los sistemas operativos. Más recientemente el uso de sistemas de Cloud Computing ha mejorado la escalabilidad y el abaratamiento de los costes para sistemas de backend, ofreciendo la posibilidad de implementar servicios Web en Internet sin la necesidad de grandes desembolsos iniciales en las áreas de infraestructuras y recursos tanto hardware como software. Sin embargo no existen aún muchas iniciativas con el objetivo de realizar sistemas de videoconferencia que aprovechen las ventajas del Cloud. Esta tesis doctoral propone un conjunto de técnicas, interfaces y algoritmos para la implentación de sistemas de videoconferencia en infraestructuras tanto públicas como privadas de Cloud Computing. Las técnicas propuestas en la tesis se basan en la realización de un servicio básico de videoconferencia que se ejecuta directamente en el navegador sin la necesidad de instalar ningún tipo de aplicación de escritorio. Para ello el desarrollo de esta tesis parte de una aplicación RIA con tecnologías que hoy en día permiten acceder a la cámara y al micrófono directamente desde el navegador, y enviar los datos que capturan a través de la conexión de Internet. Además se han implementado interfaces que permiten a usuarios finales la participación en salas de videoconferencia que se ejecutan en servidores de proveedores de Cloud. Para ello se partió de los resultados obtenidos en las técnicas anteriores de ejecución de aplicaciones en el navegador y se implementaron los recursos de backend en la nube. Además se modificó un servicio ya existente implementado en el departamento para adaptarlo a los requisitos típicos de las infraestructuras de Cloud Computing. Alcanzado este punto se procedió a analizar si las infraestructuras propias de los proveedores públicos de Cloud Computing podrían soportar el tráfico generado por los sistemas que se habían adaptado. Este análisis se centró tanto a nivel de red como a nivel de capacidad de procesamiento y estabilidad de los sistemas. Para los pasos de análisis y validación de los sistemas Cloud se tomaron consideraciones más generales para abarcar casos como el procesamiento de datos multimedia en la nube, campo en el que comienza a haber bastante investigación en los últimos años. Como último paso se ideó una metodología de implementación de este tipo de aplicaciones para que fuera posible abaratar los costes de los sistemas de videoconferencia haciendo uso de clouds híbridos. Finalmente en la tesis se abre una discusión sobre las conclusiones obtenidas a lo largo de este amplio estudio, obteniendo resultados útiles en las distintas etapas de implementación de los sistemas de videoconferencia en la nube.

Interacción desde dispositivos Android vía Bluetooth, con juguete teledirigido, para su uso por personas con discapacidad

El Proyecto Fin de Carrera, con título, "Interacción desde dispositivos Android vía Bluetooth, con juguete teledirigido, para su uso por personas con discapacidad" pretende completar la primera versión de la aplicación sobre dispositivo Android para manejar un juguete teledirigido añadiendo nuevas formas de interactuar con el dispositivo Android. Para este caso, el juguete teledirigido es el mismo: el robot esférico llamado Sphero. Dicho robot posee una interfaz a través de la cual puede recibir instrucciones, y mediante las cuales, se puede poner en movimiento o iluminarse con diferentes colores. Esta ampliación facilitará la interacción del usuario con el dispositivo Android, además de ampliar la funcionalidad hacia la inversa: recibir los movimientos del robot Sphero en el dispositivo Android cuando es manejado con la mano. Completando la primera versión, como cumplimiento de este Proyecto Fin de Carrera, se han realizado una serie de mandos nuevos, los cuales abarcan desde el manejo del robot por instrucciones de voz, movimientos del dispositivo Android desde el que se ejecuta, describir una trayectoria dibujada previamente en el dispositivo Android, o, realizar una serie de movimientos corregidos mediante la aplicación gracias a los límites de movimientos para un usuario concreto que pueden introducirse. Además, completando lo anteriormente escrito, se ha desarrollado una aplicación web que registrará todos los datos de uso del juguete, la cual, explota una base de datos que almacena toda interacción con el juguete. Estos datos estarán asociados a un usuario, debido a que la aplicación Android debe perfilarse para el uso de un usuario concreto. El perfilado de usuario se ha completado añadiendo una serie de información que puede ser útil para la persona que analice el comportamiento de una persona con discapacidad que utilice la aplicación. Por último, se ha realizado un estudio de elementos externos que puedan facilitar la interacción con los dispositivos Android a personas que sufran alguna discapacidad. ABSTRACT. The Thesis, titled "Interaction from Android devices via Bluetooth, with remote control toy, for use by people with disabilities" project aims to complete the first version of the application on Android device to manage a remote control toy adding new ways of interacting to Android device. For this case, the remote control toy is the same: the spherical robot called Sphero. This robot has an interface through which it can receive instructions, and by means of which can be set in motion or illuminated with different colors. This expansion will facilitate user interaction with the Android device, and extend the functionality to reverse: receiving Sphero robot movements in the Android device when handled by hand. Completing the first version, in fulfillment of this Thesis, there have been a number of new controls, which range from control of robot by voice instructions, movements Android device from which it runs, describe a path drawn previously on your Android device, or perform a series of movements corrected by applying through limits of movement for a particular user can be made. Besides completing the above written, has developed a web application that will record all data on use of the toy, which exploits a database that stores all interaction with the toy. These data will be associated with a user, because the Android application should be outlined for the use of a particular user. The user profile is completed by adding a range of information that can be useful for the person to analyze the behavior of a disabled person to use the application. Finally, a study was made of external elements that can facilitate interaction with Android devices to people who suffer from a disability.

Fast Information Retrieval in the Open Grid Service Architecture

This is an extended version of an article presented at the Second International Conference on Software, Services and Semantic Technologies, Sofia, Bulgaria, 11–12 September 2010.

API de servicios web REST extensible dinámicamente basada en una arquitectura Plug-in para el procesado de imágenes recibidas desde dispositivos móviles

Se ha diseñado una aplicación móvil que permite examinar el riesgo de melanoma mediante el análisis de una foto. La memoria documenta la realización de una aplicación de servidor que forma parte de una solución de eHealth con un cliente ya desarrollado por un proyecto previo de fin de carrera en forma de una aplicación Android. La aplicación de servidor desarrollada expone una API de servicios web REST y presenta una arquitectura extensible dinámicamente mediante la implementación de un patrón plug-in.