18 research outputs found

    Providing security and fault tolerance in P2P connections between clouds for mHealth services

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    [EN] The mobile health (mHealth) and electronic health (eHealth) systems are useful to maintain a correct administration of health information and services. However, it is mandatory to ensure a secure data transmission and in case of a node failure, the system should not fall down. This fact is important because several vital systems could depend on this infrastructure. On the other hand, a cloud does not have infinite computational and storage resources in its infrastructure or would not provide all type of services. For this reason, it is important to establish an interrelation between clouds using communication protocols in order to provide scalability, efficiency, higher service availability and flexibility which allow the use of services, computing and storage resources of other clouds. In this paper, we propose the architecture and its secure protocol that allows exchanging information, data, services, computing and storage resources between all interconnected mHealth clouds. The system is based on a hierarchic architecture of two layers composed by nodes with different roles. The routing algorithm used to establish the connectivity between the nodes is the shortest path first (SPF), but it can be easily changed by any other one. Our architecture is highly scalable and allows adding new nodes and mHealth clouds easily, while it tries to maintain the load of the cloud balanced. Our protocol design includes node discovery, authentication and fault tolerance. We show the protocol operation and the secure system design. Finally we provide the performance results in a controlled test bench.Lloret, J.; Sendra, S.; Jimenez, JM.; Parra-Boronat, L. (2016). Providing security and fault tolerance in P2P connections between clouds for mHealth services. Peer-to-Peer Networking and Applications. 9(5):876-893. doi:10.1007/s12083-015-0378-3S87689395The Fifty-eighth World Health Assembly, Resolutions and Decisions. Document: A58/21. Available at: http://www.who.int/healthacademy/media/WHA58-28-en.pdf . [Last access: Dec. 30, 2014]World Health organization. Topics of eHealth. In WHO website. Available at: http://www.who.int/topics/eHealth/en/ . [Last access: Dec. 30, 2014]Pickup JC, Freeman SC, Sutton AJ (2011) Glycaemic control in type 1 diabetes during real time continuous glucose monitoring compared with self monitoring of blood glucose: meta-analysis of randomised controlled trials using individual patient data. BMJ 343:d3805Promotional Material Digital health: working in partnership. Department of Health. UK. (2014) Available at: https://www.gov.uk/government/publications/digital-health-working-in-partnership/digital-health-working-in-partnerships#digital-health---harnessing-technology-for-patient-benefit . [Last access: Dec. 30, 2014]eHealth for a Healthier Europe!– opportunities for a better use of healthcare resources. Available at: https://joinup.ec.europa.eu/sites/default/files/files_epractice/sites/eHealth%20for%20a%20Healthier%20Europe %20-%20Opportunities%20for%20a%20better%20use%20of%20healthcare%20resources.pdf. [Last access: Dec. 30, 2014]Adibi S (2012) Link technologies and BlackBerry mobile health (mHealth) solutions: a review. IEEE Trans Inf Technol Biomed 16(4):586–597Chiarini G, Ray P, Akter S, Masella C, Ganz A (2013) mHealth technologies for chronic diseases and elders: a systematic review. IEEE J Sel Areas Commun 31(9):6–18Lopes IM, Silva BM, Rodrigues JJ, Lloret J, Proenca ML (2011) A mobile health monitoring solution for weight control. In proceedings of the 2011 International Conference on Wireless Communications and Signal Processing (WCSP 2011), Nanjing, pp 1–5Lopes IM, Silva BM, Rodrigues JJPC, Lloret J (2012) Performance evaluation of cooperation mechanisms for m-health applications. In proceedings of the 2012 I.E. Global Communications Conference (GLOBECOM 2012), AnaheimKyriacou EC, Pattichis CS, Pattichis MS (2009) An overview of recent health care support systems for eEmergency and mHealth applications. In proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC 2009), Hilton Minneapolis, pp 1246–1249Nkosi MT, Mekuria F (2010) Cloud computing for enhanced mobile health applications. In proceedings of the 2010 I.E. Second International Conference on Cloud Computing Technology and Science (CloudCom 2010), Indianapolis, pp 629–633Sultan N (2014) Making use of cloud computing for healthcare provision: opportunities and challenges. Int J Inf Manag 34(2):177–184Pandey S, Voorsluys W, Niu S, Khandoker A, Buyya R (2012) An autonomic cloud environment for hosting ECG data analysis services. Futur Gener Comput Syst 28(1):147–154Xia H, Asif I, Zhao X (2013) Cloud-ECG for real time ECG monitoring and analysis. Comput Methods Prog Biomed 110(3):253–259Bourouis A, Feham M, Bouchachia A (2012) A new architecture of a ubiquitous health monitoring system: a prototype of cloud mobile health monitoring system. arXiv preprint. Reference: arXiv:1205.6910Chen KR, Lin YL, Huang MS (2011) A mobile biomedical device by novel antenna technology for cloud computing resource toward pervasive healthcare. In proceedings of the 11th International Conference on Bioinformatics and Bioengineering (BIBE 2011), Taichung, pp 133–136Lacuesta R, Lloret J, Sendra S, Peñalver L (2014), Spontaneous ad hoc mobile cloud computing network. Sci World J (Article ID 232419): 1–19Ghafoor KZ, Bakar KA, Mohammed MA, Lloret J (2013) Vehicular cloud computing: trends and challenges (Chapter 14). In Mobile Networks and Cloud computing Convergence for Progressive Services and Applications. IGI Global. pp. 262–274. DOI: 10.4018/978-1-4666-4781-7.ch014Wan J, Zhang D, Zhao S, Yang LT, Lloret J (2014) Context-aware vehicular cyber-physical systems with cloud support: architecture, challenges and solutions. IEEE Commun Mag 52(8):106–113. doi: 10.1109/MCOM.2014.6871677Rodrigues JJPC, Zhou L, Mendes LDP, Lin K, Lloret J (2012) Distributed media-aware flow scheduling in cloud computing environment. Comput Commun 35(15):1819–1827Dutta R, Annappa B (2014) Protection of data in unsecured public cloud environment with open, vulnerable networks using threshold-based secret sharing. Netw Protoc Algoritm 6(1):58–75Modares H, Lloret J, Moravejosharieh A, Salleh R (2013) Security in mobile cloud computing (Chapter 5). In Mobile Networks and Cloud computing Convergence for Progressive Services and Applications. IGI Global. pp. 79–91Mehmood A, Song H, Lloret J (2014) Multi-agent based framework for secure and reliable communication among open clouds. Netw Protoc Algoritm 6(4):60–76Mendes LDP, Rodrigues JJPC, Lloret J, Sendra S (2014) Cross-layer dynamic admission control for cloud-based multimedia sensor networks. IEEE Syst J 8(1):235–246Xiong J, Li F, Ma J, Liu X, Yao Z, Chen PS (2014) A full lifecycle privacy protection scheme for sensitive data in cloud computing. Peer-to-Peer Netw Appl 1–13Yang H, Kim H, Mtonga K (2014) An efficient privacy-preserving authentication scheme with adaptive key evolution in remote health monitoring system. Peer-to-Peer Netw Appl 1–11Silva BM, Rodrigues JJ, Canelo F, Lopes IM, Lloret J (2014) Towards a cooperative security system for mobile-health applications. Electron Commer Re 1–27Flynn D, Gregory P, Makki H, Gabbay M (2009) Expectations and experiences of eHealth in primary care: a qualitative practice-based investigation. Int J Med Inform 78(9):588–604Thampi SM (2010) Survey of search and replication schemes in unstructured P2P networks. Netw Protoc Algoritm 2(1):93–131Khan SM, Mallesh N, Nambiar A, Wright M (2010) The dynamics of salsa: a robust structured P2P system. Netw Protoc Algoritm 2(4):40–60Garcia M, Hammoumi M, Canovas A, Lloret J (2011) Controlling P2P file-sharing networks’ traffic. Netw Protoc Algoritm 3(4):54–92Lloret J, Garcia M, Tomas J, Rodrigues JJPC (2014) Architecture and protocol for InterCloud communication. Inf Sci 258:434–451Chowdhury CR (2014) A survey of cloud based health care system. Int J Innov Res Comput Commun Eng 2(8):5477–5481Ghosh R, Papapanagiotou I, Boloor KA (2014) Survey on research initiatives for healthcare clouds. Cloud Computing Applications for Quality Health Care Delivery. IGI Global 1–18Donahue S (2010) Can cloud computing help fix health care? Cloudbook J 1(6):1–6Deng M, Petkovic M, Nalin M, Baroni IA (2011) Home healthcare system in the cloud--addressing security and privacy challenges. In proceedings of the 2011 I.E. International Conference on Cloud Computing (CLOUD 2011), Washington, pp 549–556Wang X, Gui Q, Liu B, Chen Y, Jin Z (2013) Leveraging mobile cloud for telemedicine: a performance study in medical monitoring. In proceedings of the 39th Annual Northeast Bioengineering Conference (NEBEC 2013), Syracuse, pp 49–50Alamri A (2012) Cloud-based e-health multimedia framework for heterogeneous network. In proceedings of the 2012 I.E. International Conference on Multimedia and Expo Workshops (ICMEW 2012), Melbourne, pp 447–452Constantinescu L, Kim J, Feng DD (2012) Sparkmed: a framework for dynamic integration of multimedia medical data into distributed m-health systems. IEEE Trans Inf Technol Biomed 16(1):40–52Botts N, Thoms B, Noamani A, Horan TA (2010) Cloud computing architectures for the underserved: public health cyberinfrastructures through a network of healthatms. In proceedings of the 43rd Hawaii International Conference on System Sciences (HICSS 2010), Honolulu, pp 1–10Fan L, Buchanan W, Thummler C, Lo O, Khedim A, Uthmani O, Lawson A, Bell D (2011) DACAR platform for eHealth services cloud. In proceedings of the 2011 I.E. International Conference on Cloud Computing (CLOUD 2011), Washington, pp 219–226Ruiz-Zafra A, Benghazi K, Noguera M, Garrido JL (2013) Zappa: An Open Mobile Platform to Build Cloud-Based m-Health Systems. In proceedings of the 4th International Symposium on Ambient Intelligence (ISAmI 2013), Salamanca, pp 87–94Nijon S, Dickerson RF, Asare P, Li Q, Hong D, Stankovic JA, Hu P, Shen G, Jiang X (2013) Auditeur: a mobile-cloud service platform for acoustic event detection on smartphones. In Proceeding of the 11th annual international conference on Mobile systems, applications, and services. ACM, Taipei, pp 403–416Lloret J, Diaz JR, Boronat F, Jiménez JM (2006) A fault-tolerant P2P-based protocol for logical networks interconnection. In proceedings of the International Conference on Networking and Services (ICNS’06), Silicon ValleyLloret J, Palau C, Boronat F, Tomas J (2008) Improving networks using group-based topologies. Comput Commun 31(14):3438–3450Lloret J, Boronat Segui F, Palau C, Esteve M (2005) Two levels SPF-based system to interconnect partially decentralized P2P file sharing networks. In proceedings of the Joint International Conference on Autonomic and Autonomous Systems and International Conference on Networking and Services.(ICAS-ICNS 2005), Papeete, p 39Cramer C, Kutzner K, Fuhrmann T (2004) Bootstrapping locality-aware P2P networkS. In proceedings of the 12th IEEE International Conference on Networks (ICON 2004), Singapore, pp 357–361FIPS 180-1 - Secure Hash Standard, SHA-1. National Institute of Standards and Technology. http://www.itl.nist.gov/fipspubs/fip180-1.htm [Last access: Dec. 30, 2014]Eastlake D., Jones P., US Secure Hash Algorithm 1 (SHA1),(2001). In IETF website, Available at: http://www.ietf.org/rfc/rfc3174.txt [Last access: March 20, 2015]Lacuesta R, Lloret J, Garcia M, Peñalver L (2011) Two secure and energy-saving spontaneous Ad-Hoc protocol for wireless mesh client networks. J Netw Comput Appl 3(2):492–50

    A decentralized framework for cross administrative domain data sharing

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    Federation of messaging and storage platforms located in remote datacenters is an essential functionality to share data among geographically distributed platforms. When systems are administered by the same owner data replication reduces data access latency bringing data closer to applications and enables fault tolerance to face disaster recovery of an entire location. When storage platforms are administered by different owners data replication across different administrative domains is essential for enterprise application data integration. Contents and services managed by different software platforms need to be integrated to provide richer contents and services. Clients may need to share subsets of data in order to enable collaborative analysis and service integration. Platforms usually include proprietary federation functionalities and specific APIs to let external software and platforms access their internal data. These different techniques may not be applicable to all environments and networks due to security and technological restrictions. Moreover the federation of dispersed nodes under a decentralized administration scheme is still a research issue. This thesis is a contribution along this research direction as it introduces and describes a framework, called \u201cWideGroups\u201d, directed towards the creation and the management of an automatic federation and integration of widely dispersed platform nodes. It is based on groups to exchange messages among distributed applications located in different remote datacenters. Groups are created and managed using client side programmatic configuration without touching servers. WideGroups enables the extension of the software platform services to nodes belonging to different administrative domains in a wide area network environment. It lets different nodes form ad-hoc overlay networks on-the-fly depending on message destinations located in distinct administrative domains. It supports multiple dynamic overlay networks based on message groups, dynamic discovery of nodes and automatic setup of overlay networks among nodes with no server-side configuration. I designed and implemented platform connectors to integrate the framework as the federation module of Message Oriented Middleware and Key Value Store platforms, which are among the most widespread paradigms supporting data sharing in distributed systems

    Estudio del rendimiento de arquitecturas basadas en grupos para WAHSN

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    [ES] Existen muchos trabajos relacionados con las redes ad hoc y las redes de sensores donde se presentan nuevos protocolos que encaminamiento que aportan mejores características, otros trabajos donde se comparan para ver cual posee un mejor rendimiento ó incluso presentan nuevas aplicaciones basadas en este tipo de redes, pero este trabajo aporta otro punto de vista. ¿Por que no ver la red como un conjunto que se divide en grupos para aportar un mejor rendimiento a la red independientemente del protocolo de encaminamiento utilizado?. Para ello, en este trabajo, vamos a demostrar a través de simulaciones, que la agrupación de nodos en redes WAHSN (Wireless Ad Hoc & Sensor Networks) aporta mejoras a la red en general, disminuyendo el tráfico de encaminamiento, el retardo, el throughput, etc. Este estudio se ha realizado evaluando los protocolos estándar más utilizados (DSR [1], AODV [2] y OLSR [3]), así podemos observar cual de ellos aporta un mejor rendimiento. Finalmente, se propone una arquitectura de red basada en grupos optimizada para las redes WAHSN[EN] There are many works related with ad hoc networks and sensor networks where the authors present new routing protocols with better or enhanced features, others just compare the performance of them or present an application environment, but this work tries to give another point of view. Why don¿t we see the network as a whole and split it intro groups to give better performance to the network regardless of the used routing protocol?. First, we will demonstrate, through simulations, that grouping nodes in WAHSN (Wireless Ad Hoc & Sensor Networks) improves the whole network by diminishing the routing traffic, the delay, the throughput, etc. This study was conducted to assess the most used standard protocols (DSR [1], AODV [2] and OLSR [3]) that gives better performance to the whole network when there are groups of nodes. Finally, a group-based network architecture optimized for WAHSN is proposedGarcía Pineda, M. (2008). Estudio del rendimiento de arquitecturas basadas en grupos para WAHSN. http://hdl.handle.net/10251/13472Archivo delegad

    Design and Implementation of a Communication Protocol to Improve Multimedia QoS and QoE in Wireless Ad Hoc Networks

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    [EN] This dissertation addresses the problem of multimedia delivery over multi-hop ad hoc wireless networks, and especially over wireless sensor networks. Due to their characteristics of low power consumption, low processing capacity and low memory capacity, they have major difficulties in achieving optimal quality levels demanded by end users in such communications. In the first part of this work, it has been carried out a study to determine the behavior of a variety of multimedia streams and how they are affected by the network conditions when they are transmitted over topologies formed by devices of different technologies in multi hop wireless ad hoc mode. To achieve this goal, we have performed experimental tests using a test bench, which combine the main codecs used in audio and video streaming over IP networks with different sound and video captures representing the characteristic patterns of multimedia services such as phone calls, video communications, IPTV and video on demand (VOD). With the information gathered in the laboratory, we have been able to establish the correlation between the induced changes in the physical and logical topology and the network parameters that measure the quality of service (QoS) of a multimedia transmission, such as latency, jitter or packet loss. At this stage of the investigation, a study was performed to determine the state of the art of the proposed protocols, algorithms, and practical implementations that have been explicitly developed to optimize the multimedia transmission over wireless ad hoc networks, especially in ad hoc networks using clusters of nodes distributed over a geographic area and wireless sensor networks. Next step of this research was the development of an algorithm focused on the logical organization of clusters formed by nodes capable of adapting to the circumstances of real-time traffic. The stated goal was to achieve the maximum utilization of the resources offered by the set of nodes that forms the network, allowing simultaneously sending reliably and efficiently all types of content through them, and mixing conventional IP data traffic with multimedia traffic with stringent QoS and QoE requirements. Using the information gathered in the previous phase, we have developed a network architecture that improves overall network performance and multimedia streaming. In parallel, it has been designed and programmed a communication protocol that allows implementing the proposal and testing its operation on real network infrastructures. In the last phase of this thesis we have focused our work on sending multimedia in wireless sensor networks (WSN). Based on the above results, we have adapted both the architecture and the communication protocol for this particular type of network, whose use has been growing hugely in recent years.[ES] Esta tesis doctoral aborda el problema de la distribución de contenidos multimedia a través de redes inalámbricas ad hoc multisalto, especialmente las redes inalámbricas de sensores que, debido a sus características de bajo consumo energético, baja capacidad de procesamiento y baja capacidad de memoria, plantean grandes dificultades para alcanzar los niveles de calidad óptimos que exigen los usuarios finales en dicho tipo de comunicaciones. En la primera parte de este trabajo se ha llevado a cabo un estudio para determinar el comportamiento de una gran variedad de flujos multimedia y como se ven afectados por las condiciones de la red cuando son transmitidos a través topologías formadas por dispositivos de diferentes tecnologías que se comunican en modo ad hoc multisalto inalámbrico. Para ello, se han realizado pruebas experimentales sobre una maqueta de laboratorio, combinando los principales códecs empleados en la transmisión de audio y video a través de redes IP con diversas capturas de sonido y video que representan patrones característicos de servicios multimedia tales como las llamadas telefónicas, videoconferencias, IPTV o video bajo demanda (VOD). Con la información reunida en el laboratorio se ha podido establecer la correlación entre los cambios inducidos en la topología física y lógica de la red con los parámetros que miden la calidad de servicio (QoS) de una transmisión multimedia, tales como la latencia el jitter o la pérdida de paquetes. En esta fase de la investigación se realiza un estudio para determinar el estado del arte de las propuestas de desarrollo e implementación de protocolos y algoritmos que se han generado de forma explícita para optimizar la transmisión de tráfico multimedia sobre redes ad hoc inalámbricas, especialmente en las redes inalámbricas de sensores y redes ad hoc utilizando clústeres de nodos distribuidos en un espacio geográfico. El siguiente paso en la investigación ha consistido en el desarrollo de un algoritmo propio para la organización lógica de clústeres formados por nodos capaces de adaptarse a las circunstancias del tráfico en tiempo real. El objetivo planteado es conseguir un aprovechamiento máximo de los recursos ofrecidos por el conjunto de nodos que forman la red, permitiendo de forma simultánea el envío de todo tipo de contenidos a través de ellos de forma confiable y eficiente, permitiendo la convivencia de tráfico de datos IP convencional con tráfico multimedia con requisitos exigentes de QoS y QoE. A partir de la información conseguida en la fase anterior, se ha desarrollado una arquitectura de red que mejora el rendimiento general de la red y el de las transmisiones multimedia de audio y video en particular. De forma paralela, se ha diseñado y programado un protocolo de comunicación que permite implementar el modelo y testear su funcionamiento sobre infraestructuras de red reales. En la última fase de esta tesis se ha dirigido la atención hacia la transmisión multimedia en las redes de sensores inalámbricos (WSN). Partiendo de los resultados anteriores, se ha adaptado tanto la arquitectura como el protocolo de comunicaciones para este tipo concreto de red, cuyo uso se ha extendido en los últimos años de forma considerable[CA] Esta tesi doctoral aborda el problema de la distribució de continguts multimèdia a través de xarxes sense fil ad hoc multi salt, especialment les xarxes sense fil de sensors que, a causa de les seues característiques de baix consum energètic, baixa capacitat de processament i baixa capacitat de memòria, plantegen grans dificultats per a aconseguir els nivells de qualitat òptims que exigixen els usuaris finals en eixos tipus de comunicacions. En la primera part d'este treball s'ha dut a terme un estudi per a determinar el comportament d'una gran varietat de fluxos multimèdia i com es veuen afectats per les condicions de la xarxa quan són transmesos a través topologies formades per dispositius de diferents tecnologies que es comuniquen en mode ad hoc multi salt sense fil. Per a això, s'han realitzat proves experimentals sobre una maqueta de laboratori, combinant els principals códecs empleats en la transmissió d'àudio i vídeo a través de xarxes IP amb diverses captures de so i vídeo que representen patrons característics de serveis multimèdia com son les cridades telefòniques, videoconferències, IPTV o vídeo baix demanda (VOD). Amb la informació reunida en el laboratori s'ha pogut establir la correlació entre els canvis induïts en la topologia física i lògica de la xarxa amb els paràmetres que mesuren la qualitat de servei (QoS) d'una transmissió multimèdia, com la latència el jitter o la pèrdua de paquets. En esta fase de la investigació es realitza un estudi per a determinar l'estat de l'art de les propostes de desenvolupament i implementació de protocols i algoritmes que s'han generat de forma explícita per a optimitzar la transmissió de tràfic multimèdia sobre xarxes ad hoc sense fil, especialment en les xarxes sense fil de sensors and xarxes ad hoc utilitzant clusters de nodes distribuïts en un espai geogràfic. El següent pas en la investigació ha consistit en el desenvolupament d'un algoritme propi per a l'organització lògica de clusters formats per nodes capaços d'adaptar-se a les circumstàncies del tràfic en temps real. L'objectiu plantejat és aconseguir un aprofitament màxim dels recursos oferits pel conjunt de nodes que formen la xarxa, permetent de forma simultània l'enviament de qualsevol tipus de continguts a través d'ells de forma confiable i eficient, permetent la convivència de tràfic de dades IP convencional amb tràfic multimèdia amb requisits exigents de QoS i QoE. A partir de la informació aconseguida en la fase anterior, s'ha desenvolupat una arquitectura de xarxa que millora el rendiment general de la xarxa i el de les transmissions multimèdia d'àudio i vídeo en particular. De forma paral¿lela, s'ha dissenyat i programat un protocol de comunicació que permet implementar el model i testejar el seu funcionament sobre infraestructures de xarxa reals. En l'última fase d'esta tesi s'ha dirigit l'atenció cap a la transmissió multimèdia en les xarxes de sensors sense fil (WSN). Partint dels resultats anteriors, s'ha adaptat tant l'arquitectura com el protocol de comunicacions per a aquest tipus concret de xarxa, l'ús del qual s'ha estés en els últims anys de forma considerable.Díaz Santos, JR. (2016). Design and Implementation of a Communication Protocol to Improve Multimedia QoS and QoE in Wireless Ad Hoc Networks [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/62162TESI

    A Cluster-Based Architecture to Structure the Topology of Parallel Wireless Sensor Networks

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    A wireless sensor network is a self-configuring network of mobile nodes connected by wireless links where the nodes have limited capacity and energy. In many cases, the application environment requires the design of an exclusive network topology for a particular case. Cluster-based network developments and proposals in existence have been designed to build a network for just one type of node, where all nodes can communicate with any other nodes in their coverage area. Let us suppose a set of clusters of sensor nodes where each cluster is formed by different types of nodes (e.g., they could be classified by the sensed parameter using different transmitting interfaces, by the node profile or by the type of device: laptops, PDAs, sensor etc.) and exclusive networks, as virtual networks, are needed with the same type of sensed data, or the same type of devices, or even the same type of profiles. In this paper, we propose an algorithm that is able to structure the topology of different wireless sensor networks to coexist in the same environment. It allows control and management of the topology of each network. The architecture operation and the protocol messages will be described. Measurements from a real test-bench will show that the designed protocol has low bandwidth consumption and also demonstrates the viability and the scalability of the proposed architecture. Our ccluster-based algorithm is compared with other algorithms reported in the literature in terms of architecture and protocol measurements

    Cooperation in open, decentralized, and heterogeneous computer networks

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    Community Networks (CN) are naturally open and decentralized structures, that grow organically with the addition of heterogeneous network devices, contributed and configured as needed by their participants. The continuous growth in popularity and dissemination of CNs in recent years has raised the perception of a mature and sustainable model for the provisioning of networking services. However, because such infrastructures include uncontrolled entities with non delimited responsibilities, every single network entity does indeed represent a potential single-point of failure that can stop the entire network from working, and that no other entity can prevent or even circumvent. Given the open and decentralized nature of CNs, that brings together individuals and organizations with different and even conflicting economic, political, and technical interests, the achievement of no more than basic consensus on the correctness of all network nodes is challenging. In such environment, the lack of self-determination for CN participants in terms of control and security of routing can be regarded as an obstacle for growth or even as a risk of collapse. To address this problem we first consider deployments of existing Wireless CN and we analyze their technology, characteristics, and performance. We perform an experimental evaluation of a production 802.11an Wireless CN, and compare to studies of other Wireless CN deployments in the literature. We compare experimentally obtained throughput traces with path-capacity calculations based on well-known conflict graph models. We observe that in the majority of cases the path chosen by the employed BMX6 routing protocol corresponds with the best identified path in our model. We analyze monitoring and interaction shortcomings of CNs and address these with Network Characterization Tool (NCT), a novel tool that allows users to assess network state and performance, and improve their quality of experience by individually modifying the routing parameters of their devices. We also evaluate performance outcomes when different routing policies are in use. Routing protocols provide self-management mechanisms that allow the continuous operation of a Community Mesh Network (CMN). We focus on three widely used proactive mesh routing protocols and their implementations: BMX6, OLSR, and Babel. We describe the core idea behind these protocols and study the implications of these in terms of scalability, performance, and stability by exposing them to typical but challenging network topologies and scenarios. Our results show the relative merits, costs, and limitations of the three protocols. Built upon the studied characteristics of typical CN deployments, their requirements on open and decentralized cooperation, and the potential controversy on the trustiness of particular components of a network infrastructure, we propose and evaluate SEMTOR, a novel routing-protocol that can satisfy these demands. SEMTOR allows the verifiable and undeniable definition and distributed application of individually trusted topologies for routing traffic towards each node. One unique advantage of SEMTOR is that it does not require a global consensus on the trustiness of any node and thus preserves cooperation among nodes with even oppositional defined trust specification. This gives each node admin the freedom to individually define the subset, and the resulting sub-topology, from the whole set of participating nodes that he considers sufficiently trustworthy to meet their security, data-delivery objectives and concerns. The proposed mechanisms have been realized as a usable and open-source implementation called BMX7, as successor of BMX6. We have evaluated its scalability, contributed robustness, and security. These results show that the usage of SEMTOR for securing trusted routing topologies is feasible, even when executed on real and very cheap (10 Euro, Linux SoC) routers as commonly used in Community Mesh Networks.Las Redes Comunitarias (CNs) son estructuras de naturaleza abierta y descentralizada, que crecen orgánicamente con la adición de dispositivos de red heterogéneos que aportan y configuran sus participantes según sea necesario. Sin embargo, debido a que estas infraestructuras incluyen entidades con responsabilidades poco delimitadas, cada entidad puede representar un punto de fallo que puede impedir que la red funcione y que ninguna otra entidad pueda prevenir o eludir. Dada la naturaleza abierta y descentralizada de las CNs, que agrupa individuos y organizaciones con diferentes e incluso contrapuestos intereses económicos, políticos y técnicos, conseguir poco más que un consenso básico sobre los nodos correctos en la red puede ser un reto. En este entorno, la falta de autodeterminación para los participantes de una CN en cuanto a control y seguridad del encaminamiento puede considerarse un obstáculo para el crecimiento o incluso un riesgo de colapso. Para abordar este problema consideramos las implementaciones de redes comunitarias inalámbricas (WCN) y se analiza su tecnología, características y desempeño. Realizamos una evaluación experimental de una WCN establecida y se compara con estudios de otros despliegues. Comparamos las trazas de rendimiento experimentales con cálculos de la capacidad de los caminos basados en modelos bien conocidos del grafo. Se observa que en la mayoría de los casos el camino elegido por el protocolo de encaminamiento BMX6 corresponde con el mejor camino identificado en nuestro modelo. Analizamos las limitaciones de monitorización e interacción en CNs y los tratamos con NCT, una nueva herramienta que permite evaluar el estado y rendimiento de la red, y mejorar la calidad de experiencia modificando los parámetros de sus dispositivos individuales. También evaluamos el rendimiento resultante para diferentes políticas de encaminamiento. Los protocolos de encaminamiento proporcionan mecanismos de autogestión que hacen posible el funcionamiento continuo de una red comunitaria mesh (CMN). Nos centramos en tres protocolos de encaminamiento proactivos para redes mesh ampliamente utilizados y sus implementaciones: BMX6, OLSR y Babel. Se describe la idea central de estos protocolos y se estudian la implicaciones de éstos en términos de escalabilidad, rendimiento y estabilidad al exponerlos a topologías y escenarios de red típicos pero exigentes. Nuestros resultados muestran los méritos, costes y limitaciones de los tres protocolos. A partir de las características analizadas en despliegues típicos de redes comunitarias, y de las necesidades en cuanto a cooperación abierta y descentralizada, y la esperable divergencia sobre la confiabilidad en ciertos componentes de la infraestructura de red, proponemos y evaluamos SEMTOR, un nuevo protocolo de encaminamiento que puede satisfacer estas necesidades. SEMTOR permite definir de forma verificable e innegable, así como aplicar de forma distribuida, topologías de confianza individualizadas para encaminar tráfico hacia cada nodo. Una ventaja única de SEMTOR es que no precisa de consenso global sobre la confianza en cualquier nodo y por tanto preserva la cooperación entre los nodos, incluso con especificaciones de confianza definidas por oposición. Esto proporciona a cada administrador de nodo la libertad para definir el subconjunto, y la sub-topología resultante, entre el conjunto de todos los nodos participantes que considere dignos de suficiente confianza para cumplir con su objetivo y criterio de seguridad y entrega de datos. Los mecanismos propuestos se han realizado en forma de una implementación utilizable de código abierto llamada BMX7. Se ha evaluado su escalabilidad, robustez y seguridad. Estos resultados demuestran que el uso de SEMTOR para asegurar topologías de encaminamiento de confianza es factible, incluso cuando se ejecuta en routers reales y muy baratos utilizados de forma habitual en WCN.Postprint (published version

    A new Z39.50 protocol client to search in libraries and improve research collaboration

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    The increasing number of information available at libraries and the necessity to find a mechanism to look for information at several libraries at the same time promoted to the creation of the Z39.50 protocol. Since it has been launched, many Z39.50 clients have been developed, but most of them only have access to a reduced number of libraries catalogues and are focused on the point of view of the library users. We present a Z39.50 client that adds new features focused on the point of view of researchers and publishing houses. With our proposal the user can add the catalogue of any library whenever he wants in order to facilitate the process of looking for the desired information. Our Z39.50 client shows as well the situation of the closest libraries where the results of the information searched by the user is located. Finally, we have compared our Z39.50 client with the existing ones.Rego Mañez, A.; García-García, L.; Llopis, M.; Lloret, J. (2016). A new Z39.50 protocol client to search in libraries and improve research collaboration. Network Protocols and Algorithms. 8(3):29-54. doi:10.5296/npa.v8i3.10147S29548

    A Cognitive Routing framework for Self-Organised Knowledge Defined Networks

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    This study investigates the applicability of machine learning methods to the routing protocols for achieving rapid convergence in self-organized knowledge-defined networks. The research explores the constituents of the Self-Organized Networking (SON) paradigm for 5G and beyond, aiming to design a routing protocol that complies with the SON requirements. Further, it also exploits a contemporary discipline called Knowledge-Defined Networking (KDN) to extend the routing capability by calculating the “Most Reliable” path than the shortest one. The research identifies the potential key areas and possible techniques to meet the objectives by surveying the state-of-the-art of the relevant fields, such as QoS aware routing, Hybrid SDN architectures, intelligent routing models, and service migration techniques. The design phase focuses primarily on the mathematical modelling of the routing problem and approaches the solution by optimizing at the structural level. The work contributes Stochastic Temporal Edge Normalization (STEN) technique which fuses link and node utilization for cost calculation; MRoute, a hybrid routing algorithm for SDN that leverages STEN to provide constant-time convergence; Most Reliable Route First (MRRF) that uses a Recurrent Neural Network (RNN) to approximate route-reliability as the metric of MRRF. Additionally, the research outcomes include a cross-platform SDN Integration framework (SDN-SIM) and a secure migration technique for containerized services in a Multi-access Edge Computing environment using Distributed Ledger Technology. The research work now eyes the development of 6G standards and its compliance with Industry-5.0 for enhancing the abilities of the present outcomes in the light of Deep Reinforcement Learning and Quantum Computing

    Application of service composition mechanisms to Future Networks architectures and Smart Grids

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    Aquesta tesi gira entorn de la hipòtesi de la metodologia i mecanismes de composició de serveis i com es poden aplicar a diferents camps d'aplicació per a orquestrar de manera eficient comunicacions i processos flexibles i sensibles al context. Més concretament, se centra en dos camps d'aplicació: la distribució eficient i sensible al context de contingut multimèdia i els serveis d'una xarxa elèctrica intel·ligent. En aquest últim camp es centra en la gestió de la infraestructura, cap a la definició d'una Software Defined Utility (SDU), que proposa una nova manera de gestionar la Smart Grid amb un enfocament basat en programari, que permeti un funcionament molt més flexible de la infraestructura de xarxa elèctrica. Per tant, revisa el context, els requisits i els reptes, així com els enfocaments de la composició de serveis per a aquests camps. Fa especial èmfasi en la combinació de la composició de serveis amb arquitectures Future Network (FN), presentant una proposta de FN orientada a serveis per crear comunicacions adaptades i sota demanda. També es presenten metodologies i mecanismes de composició de serveis per operar sobre aquesta arquitectura, i posteriorment, es proposa el seu ús (en conjunció o no amb l'arquitectura FN) en els dos camps d'estudi. Finalment, es presenta la investigació i desenvolupament realitzat en l'àmbit de les xarxes intel·ligents, proposant diverses parts de la infraestructura SDU amb exemples d'aplicació de composició de serveis per dissenyar seguretat dinàmica i flexible o l'orquestració i gestió de serveis i recursos dins la infraestructura de l'empresa elèctrica.Esta tesis gira en torno a la hipótesis de la metodología y mecanismos de composición de servicios y cómo se pueden aplicar a diferentes campos de aplicación para orquestar de manera eficiente comunicaciones y procesos flexibles y sensibles al contexto. Más concretamente, se centra en dos campos de aplicación: la distribución eficiente y sensible al contexto de contenido multimedia y los servicios de una red eléctrica inteligente. En este último campo se centra en la gestión de la infraestructura, hacia la definición de una Software Defined Utility (SDU), que propone una nueva forma de gestionar la Smart Grid con un enfoque basado en software, que permita un funcionamiento mucho más flexible de la infraestructura de red eléctrica. Por lo tanto, revisa el contexto, los requisitos y los retos, así como los enfoques de la composición de servicios para estos campos. Hace especial hincapié en la combinación de la composición de servicios con arquitecturas Future Network (FN), presentando una propuesta de FN orientada a servicios para crear comunicaciones adaptadas y bajo demanda. También se presentan metodologías y mecanismos de composición de servicios para operar sobre esta arquitectura, y posteriormente, se propone su uso (en conjunción o no con la arquitectura FN) en los dos campos de estudio. Por último, se presenta la investigación y desarrollo realizado en el ámbito de las redes inteligentes, proponiendo varias partes de la infraestructura SDU con ejemplos de aplicación de composición de servicios para diseñar seguridad dinámica y flexible o la orquestación y gestión de servicios y recursos dentro de la infraestructura de la empresa eléctrica.This thesis revolves around the hypothesis the service composition methodology and mechanisms and how they can be applied to different fields of application in order to efficiently orchestrate flexible and context-aware communications and processes. More concretely, it focuses on two fields of application that are the context-aware media distribution and smart grid services and infrastructure management, towards a definition of a Software-Defined Utility (SDU), which proposes a new way of managing the Smart Grid following a software-based approach that enable a much more flexible operation of the power infrastructure. Hence, it reviews the context, requirements and challenges of these fields, as well as the service composition approaches. It makes special emphasis on the combination of service composition with Future Network (FN) architectures, presenting a service-oriented FN proposal for creating context-aware on-demand communication services. Service composition methodology and mechanisms are also presented in order to operate over this architecture, and afterwards, proposed for their usage (in conjunction or not with the FN architecture) in the deployment of context-aware media distribution and Smart Grids. Finally, the research and development done in the field of Smart Grids is depicted, proposing several parts of the SDU infrastructure, with examples of service composition application for designing dynamic and flexible security for smart metering or the orchestration and management of services and data resources within the utility infrastructure
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