Registry composition in ambient networks

Ambient Networks (AN) is a new networking concept for beyond 3G. It is a product of the European Union's Sixth Framework Program (FP6). Network composition is a core concept of ANs. It allows dynamic, scalable and uniform cooperation between heterogeneous networks. ANs can host various registries. These registries may be of different types (e.g. centralized, distributed), store heterogeneous types of information (e.g. raw data vs. aggregated data), and rely on different interfaces to access the stored information (i.e. protocols or programming interfaces). When ANs compose, the hosted registries need to compose. Registry composition is a sub-process of network composition. It provides seamless and autonomous access to the content of all of the registries in the composed network. This thesis proposes a new architecture for registry composition in ANs. This overall architecture is made up of four components: interface interworking, data interworking, negotiation and signaling. Interface interworking enables dynamic intercommunication between registries with heterogeneous interfaces. Data interworking involves dynamically overcoming data heterogeneity (e.g. format and granularity). Interface and data interworking go beyond static interworking using gateways, as done today. The negotiation component allows the negotiation of the composition agreement. Signaling coordinates and regulates the negotiation and the execution of the composition agreement. Requirements are derived and related work is reviewed. We propose a new functional entity and a new procedure to orchestrate the composition process. We also propose a new architecture for interface interworking, based on a peer to peer overlay network. We have built a proof-of-concept prototype. The interface-interworking component is used as the basis of our new architecture to data interworking. This architecture reuses mechanisms and algorithms from the federated data base area. The thesis proposes as well a new architecture for on-line negotiation. The architecture includes a template for composition agreement proposals, and a negotiation protocol that was validated using SPIN. A new signaling framework is also proposed. It is based on the IETF Next Step in Signaling (NSIS) framework and was validated using OPNET. Most of these contributions are now part of the AN concept, as defined by the European Union's Sixth Framework Progra

Discovery and Push Notification Mechanisms for Mobile Cloud Services

Viimase viie aasta jooksul on mobiilsed seadmed nagu sülearvutid, pihuarvutid, nutitelefonid jmt. tunginud peaaegu kõigisse inimeste igapäevaelu tegevustesse. Samuti on põhjalik teadus- ja arendustegevus mobiilsete tehnoloogiate vallas viinud märkimisväärsete täiustusteni riistvara, tarkvara ja andmeedastuse alal. Tänapäeval on mobiilsed seadmed varustatud sisseehitatud sensorite, kaamera, puutetundliku ekraani, suurema hulga mäluga, kuid ka tõhusamate energiatarbemehhanismidega. Lisaks on iOS ja Android operatsioonisüsteemide väljalaske tõttu suurenenud nii mobiilirakenduste arv kui keerukus, pakkudes arvukamalt kõrgetasemelisi rakendusi. Sarnaselt on toimunud olulised arengud ja standardiseerimisele suunatud jõupingutused veebiteenusete valdkonnas ja elementaarsetele veebiteenuste ligipääsu kasutatakse laialdaselt nutitelefonidest. See on viinud loogilise järgmise sammuna veebiteenuste pakkumiseni nutitelefonidest. Telefonidest veebiteenuste pakkumise kontseptsioon ei ole uus ning seda on põhjalikult uurinud Srirama, kes pakkus välja Mobile Host (Mobiilne Veebiteenuse Pakkuja) kontseptsiooni. Algne realisatsioon kasutas aga aegunud tehnoloogiaid nagu JMEE, PersonalJava, SOAP arhitektuur jne. See töö uuendab Mobile Host'i kasutades uusimaid tehnoloogiad, nagu Android OS ja REST arhitektuur, ning pakub välja teenusemootori, mis põhineb Apache Felix'il - OSGi platvormi realisatsioonil piiratud ressurssidega seadmetele. Hämmastava kiirusega toimunud arengud mobiilsete arvutuste vallas võimaldavad uue põlvkonna veebirakenduste loomist valdkondades nagu keskkonnateadlikkus, sotsiaalvõrgustikud, koostöövahendid, asukohapõhised teenused jne. Sellised rakendused saavad ära kasutada Mobile Host'i võimalusi. Selle tulemusena on klientidel ligipääs väga suurele hulgale teenustele, mistõttu tekib vajadus efektiivse teenuste avastamise mehhanismi järele. See töö pakub välja kataloogipõhise avastusmehhanismi võrgu ülekatte toega suurtele, kõrge liikuvusega võrgustikele. See mehhanism toetub OWL-S'le, mis on ontoloogia veebiteenuseid pakkuvate ressursside avastamiseks, väljakutseks, koostamiseks ja jälgimiseks. Töö kirjeldab ka Srirama välja pakutud algupärast teenuste avastamise mehhanismi, mis toetub peer-to-peer võrkudele ja Apache Lucene võtmesõna otsingumootorile. Uurimuse käigus uuendatakse teenuseotsing kasutama Apache Solr'i, Apache Lucene'i viimast versiooni. Teenuste avastust testiti põhjalikult ja tulemused on töös kokkuvõtvalt välja toodud. Mobiilsete tehnoloogiate vallas uuritakse ka võimalust kasutada pilvetehnolologiat laiendamaks mobiilseadmete salvestusmahtu ja töökoormust edastades pilve andme- ja arvutusmahukad ülesanded. See soodustab keerulisemate ja võimalusrohkemate mobiilirakenduste arendust. Pilve delegeeritavate toimingute aeganõudva iseloomu tõttu aga on vajalik asünkroonne mehhanism teavitamaks kasutajat, millal töömahukad tegevused on lõpetatud. Mobiilsete pilveteenuste pakkujad ja vahevara lahendused võivad kasu saada Mobile Host'ist ja selle asünkroonsete teavituste võimekusest. Uurimus esitleb nelja teavitusmehhanismi: AC2DM, APNS, IBM MQTT ja Mobile Host'i põhine teavitus. Töö võtab kokku kvantitatiivse analüüsi tulemused ja toob välja nelja teavitamise lähenemise tugevused ja nõrkused. Lisaks kirjeldatakse CroudSTag rakenduse realisatsiooni - CroudSTag on mobiilirakendus, mille eesmärgiks on sotsiaalsete gruppide moodustamine kasutades näotuvastustehnoloogiat. CroudSTag-i realisatsioon kasutab mobiilseid pilveteenuseid ja Mobile Host'i, et pakkuda oma funktsionaalsust kasutajale.In the last lustrum the mobile devices such as laptops, PDAs, smart phones, tablets, etc. have pervaded almost all the environments where people perform their day-to-day activities. Further, the extensive Research and Development in mobile technologies has led to significant improvements in hardware, software and transmission. Similarly, there are significant developments and standardization efforts in web services domain and basic web services have been widely accessed from smart phones. This has lead to the logical next step of providing web services from the smart phones. The concept of the web service provisioning from smart phones is not new and has been extensively explored by Srirama who proposed the concept of Mobile Host. However, the original implementation considered aged technologies such as JMEE, PersonalJava, SOAP architecture among others. This work updates the Mobile Host to the latest technologies like Android OS and REST architecture and proposes a service engine based on Apache Felix, and OSGI implementation for resource constraint devices. Moreover, the astonishing speed in developments in mobile computing enable the new generation of applications from domains such as context-awareness, social network, collaborative tools, location based services, etc., which benefit from the Mobile Host service provisioning capabilities. As a result the clients have access to a huge number of services available; therefore, an efficient and effective service discovery mechanism is required. The thesis proposes a directory-based with network overlay support discovery mechanism for large networks with high mobility. The proposed discovery mechanism relies in OWL-S, an ontology for service discovery, invocation, composition, and monitoring of web resources. The work also considers the original service discovery mechanism proposed by Srirama relying in peer-to-peer networks and Apache Lucene, a keyword search engine. The study updates the service search to Apache Solr, the latest development for Apache Lucene. The service discovery was extensively tested and the results are summarized in this work. Mobile technologies are looking into the clouds for extending their capabilities in storage and processing by offloading data and process intensive tasks. This fosters the development of more complex and rich mobile applications. However, due to the time-consuming nature of the tasks delegated to the clouds, an asynchronous mechanism is necessary for notifying the user when the intensive tasks are completed. Mobile cloud service providers and Middleware solutions might benefit from Mobile Host and its asynchronous notification capabilities. The study presents four push notification mechanisms being AC2DM, APNS, IBM MQTT and Mobile Host based push notification. The work summarizes the results of a quantitative analysis and highlights the strengths and weakness of the four notifications approaches. In addition, it explains CroudSTag realization, a mobile application that aims the social group formation by means of facial recognition that relies in mobile cloud services and Mobile Host to provide its functionality to the user

Wireless Sensor Network Virtualization: A Survey

Wireless Sensor Networks (WSNs) are the key components of the emerging Internet-of-Things (IoT) paradigm. They are now ubiquitous and used in a plurality of application domains. WSNs are still domain specific and usually deployed to support a specific application. However, as WSN nodes are becoming more and more powerful, it is getting more and more pertinent to research how multiple applications could share a very same WSN infrastructure. Virtualization is a technology that can potentially enable this sharing. This paper is a survey on WSN virtualization. It provides a comprehensive review of the state-of-the-art and an in-depth discussion of the research issues. We introduce the basics of WSN virtualization and motivate its pertinence with carefully selected scenarios. Existing works are presented in detail and critically evaluated using a set of requirements derived from the scenarios. The pertinent research projects are also reviewed. Several research issues are also discussed with hints on how they could be tackled.Comment: Accepted for publication on 3rd March 2015 in forthcoming issue of IEEE Communication Surveys and Tutorials. This version has NOT been proof-read and may have some some inconsistencies. Please refer to final version published in IEEE Xplor

Service Oriented Mobile Computing

La diffusione di concetti quali Pervasive e Mobile Computing introduce nell'ambito dei sistemi distribuiti due aspetti fondamentali: la mobilità dell'utente e l'interazione con l'ambiente circostante, favorite anche dal crescente utilizzo di dispositivi mobili dotati di connettività wireless come prodotti di consumo. Per estendere le funzionalità introdotte nell'ambito dei sistemi distribuiti dalle Architetture Orientate ai Servizi (SOA) e dal paradigma peer-to-peer anche a dispositivi dalle risorse limitate (in termini di capacità computazionale, memoria e batteria), è necessario disporre di un middleware leggero e progettato tenendo in considerazione tali caratteristiche. In questa tesi viene presentato NAM (Networked Autonomic Machine), un formalismo che descrive in modo esaustivo un sistema di questo tipo; si tratta di un modello teorico per la definizione di entità hardware e software in grado di condividere le proprie risorse in modo completamente altruistico. In particolare, il lavoro si concentra sulla definizione e gestione di un determinato tipo di risorse, i servizi, che possono essere offerti ed utilizzati da dispositivi mobili, mediante meccanismi di composizione e migrazione. NSAM (Networked Service-oriented Autonomic Machine) è una specializzazione di NAM per la condivisione di servizi in una rete peer-to-peer, ed è basato su tre concetti fondamentali: schemi di overlay, composizione dinamica di servizi e auto-configurazione dei peer. Nella tesi vengono presentate anche diverse attività applicative, che fanno riferimento all'utilizzo di due middleware sviluppati dal gruppo di Sistemi Distribuiti (DSG) dell'Università di Parma: SP2A (Service Oriented Peer-to-peer Architecture), framework per lo sviluppo di applicazioni distribuite attraverso la condivisione di risorse in una rete peer-to-peer, e Jxta-Soap che consente la condivisione di Web Services in una rete peer-to-peer JXTA. Le applicazioni realizzate spaziano dall'ambito della logistica, alla creazione di comunità per l'e-learning, all'Ambient Intelligence alla gestione delle emergenze, ed hanno come denominatore comune la creazione di reti eterogenee e la condivisione di risorse anche tra dispositivi mobili. Viene inoltre messo in evidenza come tali applicazioni possano essere ottimizzate mediante l'introduzione del framework NAM descritto, per consentire la condivisione di diversi tipi di risorse in modo efficiente e proattivo

A service based approach for future internet architectures

Doktorgradsavhandling i informasjons- og kommunikasjonsteknologi, Universitetet i Agder, Grimstad, 201

Combining Cloud and sensors in a smart city environment

International audienceIn the current worldwide ICT scenario, a constantly growing number of ever more powerful devices (smartphones, sensors, household appliances, RFID devices, etc.) join the Internet, significantly impacting the global traffic volume (data sharing, voice, multimedia, etc.) and foreshadowing a world of (more or less) smart devices, or "things" in the Internet of Things (IoT) perspective. Heterogeneous resources can be aggregated and abstracted according to tailored thing-like semantics, thus enabling Things as a Service paradigm, or better a "Cloud of Things". In the Future Internet initiatives, sensor networks will assume even more of a crucial role, especially for making smarter cities. Smarter sensors will be the peripheral elements of a complex future ICT world. However, due to differences in the "appliances" being sensed, smart sensors are very heterogeneous in terms of communication technologies, sensing features and elaboration capabilities. This article intends to contribute to the design of a pervasive infrastructure where new generation services interact with the surrounding environment, thus creating new opportunities for contextualization and geo-awareness. The architecture proposal is based on Sensor Web Enablement standard specifications and makes use of the Contiki Operating System for accomplishing the IoT. Smart cities are assumed as the reference scenario

Provision, discovery and development of ubiquitous services and applications

Ph.DDOCTOR OF PHILOSOPH

Designing and experimenting coordination primitives for service oriented computing

Service Oriented Architecture (SOA) and Web Services (WS) are becoming a widely accepted device for designing and implementing distributed systems. SOAs have given an important contribution to software engineering providing a model where applications are defined by assembling together certain functionalities, called services, possibly provided by remote suppliers. The characterizing issue of SOAs consists of defining common principles to make services accessible and usable regardless their execution context. Nevertheless, the architectural specification is far from giving a complete reference application model on which systems should rely on. The specification just includes principles for achieving interoperability and reusability of services; other aspects are left to the implementing platforms. As a consequence, it is understood how services are specified in isolation and how their functionalities are made available to the requesters, but the definition of languages for describing service composition are far from being widely accepted and reveals to be an impelling challenge. In the last years, several solutions have been proposed for describing aggregated services. However, they often lack a formally defined semantics. Moreover, these solutions are often specific for a platform (e.g. WSs) and are difficult to adapt to other platforms since they rely on low level assumptions that are out of the SOA specifications. This thesis aims at providing new methodologies for implementing the coordination of services. Our framework proposes to be flexible enough to support high level languages and to provide reliable tools for testing correctness of implementation. Our approach relies on a formal model that takes the form of a process calculus specifically designed to deal with services and their coordination. The process calculus has been the main tool driving the specification issues as well the implementation issues. Indeed, it acts as a bridge between the high level specification language and the run-time environment. A distinguished feature of our proposal is that our formal model, i.e. the process calculus, describes distributed processes relying on an event notification mechanism as machinery for interactions. Services are represented by certain components that embody local computations and react to changes of the overall environment in which they are involved. The adoption of event notification results particularly fashionable for tackling service coordination. The principles studied at specification level are from one side understood within a theoretical framework that provides instruments for checking correctness of interaction policies and from the other side offers the core model for implementing and experimenting a programming middleware

Distributed coordination in unstructured intelligent agent societies

Current research on multi-agent coordination and distributed problem solving is still not robust or scalable enough to build large real-world collaborative agent societies because it relies on either centralised components with full knowledge of the domain or pre-defined social structures. Our approach allows overcoming these limitations by using a generic coordination framework for distributed problem solving on totally unstructured environments that enables each agent to decompose problems into sub-problems, identify those which it can solve and search for other agents to delegate the sub-problems for which it does not have the necessary knowledge or resources. Regarding the problem decomposition process, we have developed two distributed versions of the Graphplan planning algorithm. To allow an agent to discover other agents with the necessary skills for dealing with unsolved sub-problems, we have created two peer-to-peer search algorithms that build and maintain a semantic overlay network that connects agents relying on dependency relationships, which improves future searches. Our approach was evaluated using two different scenarios, which allowed us to conclude that it is efficient, scalable and robust, allowing the coordinated distributed solving of complex problems in unstructured environments without the unacceptable assumptions of alternative approaches developed thus far.As abordagens actuais de coordenação multi-agente e resolução distribuída de problemas não são suficientemente robustas ou escaláveis para criar sociedades de agentes colaborativos uma vez que assentam ou em componentes centralizados com total conhecimento do domínio ou em estruturas sociais pré-definidas. A nossa abordagem permite superar estas limitações através da utilização de um algoritmo genérico de coordenação de resolução distribuída de problemas em ambientes totalmente não estruturados, o qual permite a cada agente decompor problemas em sub-problemas, identificar aqueles que consegue resolver e procurar outros agentes a quem delegar os subproblemas para os quais não tem conhecimento suficiente. Para a decomposição de problemas, criámos duas versões distribuídas do algoritmo de planeamento Graphplan. Para procurar os agentes com as capacidades necessárias à resolução das partes não resolvidas do problema, criámos dois algoritmos de procura que constroem e mantêm uma camada de rede semântica que relaciona agentes dependentes com o fim de facilitar as procuras. A nossa abordagem foi avaliada em dois cenários diferentes, o que nos permitiu concluir que ´e uma abordagem eficiente, escalável e robusta, possibilitando a resolução distribuída e coordenada de problemas complexos em ambientes não estruturados sem os pressupostos inaceitáveis em que assentava o trabalho feito até agora