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Avaliação de roteamento em redes P2P visando obtenção de QoS na busca de serviço em nuvem; Evaluation of routing in P2P networks in order to obtain QoS in search of cloud service

Leite Filho, Dionisio Machado
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 25/04/2012 Português
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Este trabalho apresenta a avaliação de diferentes algoritmos de roteamento utilizados na camada lógica ponto a ponto (P2P) adotada por um Metaescalonador que provê Qualidade de Serviços (QoS) na Computação em Nuvem. Experimentos mostram a superioridade de três algoritmos de roteamento P2P (BCR, Chord e Pastry) em relação à utilização de Round Robin, analisando-se o tempo de resposta e a variabilidade entre os resultados obtidos em diferentes testes. Os experimentos consideram, além dos algoritmos de roteamento, a influência do número de usuários e do tipo de serviço requisitado e como esses fatores interagem entre si. É apresentado ainda um estudo sobre a melhor métrica a ser adotada para representar as informações da rede. As métricas consideradas foram latência e número de saltos. Os resultados obtidos permitem determinar, com base nos objetivos especificados, qual o impacto dos sistemas P2P utilizados pelo metaescalonador na busca e descoberta de serviços em relação à forma como a qualidade de serviços é abordada; This work presents an evaluation of different routing algorithms that are employed in a logical layer peer-to-peer (P2P) that are adopted by a Metascheduler that provides quality of services (QoS) in Cloud Computing. The experiments show the superiority of three P2P routing algorithms (BCR...

Abordagem de teoria dos jogos evolucionários para modelagem de aplicações de live streaming em redes peer-to-peer; Evolutionary game theory approach for modeling live streaming applications over peer-to-peer networks

Watanabe, Sandra Satyko Guimarães
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
Português
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Existe um interesse crescente do mercado por aplicações de multimídia em streaming via rede. Particularmente, as aplicações de live streaming que utilizam a tecnologia de redes P2P para a disseminação de conteúdo têm sido alvo de grande atenção. Aplicações como PPLive e PPStream provam que as aplicações de live streaming em redes P2P são uma realidade com relação à tecnologia atual. Os sistemas de live streaming fornecem um serviço de multicast no nível de aplicação para transmissões ao vivo na Internet. Essas aplicações de live streaming, quando executadas em redes P2P, têm potencial para serem altamente robustas, escaláveis e adaptativas devido à redundância e não dependência de recursos particulares dentre os nodos participantes. Porém, para fazer uso de todas as vantagens disponíveis, a aplicação deve contornar alguns desafios: i) manter a qualidade de playback mesmo com a inerente dinamicidade das redes P2P; ii) impedir que nodos incorretos escondam ações maliciosas atrás do anonimato que existe em P2P; iii) manter a taxa de upload dos nodos participantes da aplicação em um nível aceitável. A taxa de upload dos nodos é muito importante porque a aplicação de live streaming em P2P é uma aplicação cooperativa. Desta forma...

On the investigation of the joint use of self-* properties and peer-to-peer for network management; Investigação do uso integrado de propriedades self-* e peer-to-peer para o gerenciamento de redes

Marquezan, Clarissa Cassales
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
Português
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Ao longo dos anos, a comunidade de gerenciamento de redes têm sido levada a criar alternativas de gerenciamento que sejam capazes de lidar com problemas de heterogeneidade, escalabilidade, confiabilidade, e com a redução da intervenção humana. Atualmente, existem duas principais alternativas empregadas na definição e desenvolvimento de soluções de gerenciamento de redes. A primeira utiliza computação autonômica e propriedades self-*, enquanto a segunda utiliza conceitos e tecnologias peer-to-peer (P2P). Geralmente, as investigações relacionadas com a aplicação de computação autonômica e propriedades self-* no gerenciamento de redes são focadas na definição de modelos de alto nível (ex., ontologias e políticas), os quais são capazes de determinar as ações autônomas do sistema. Em contrapartida, pesquisas relacionadas com P2P no gerenciamento de redes estão mais focadas na definição da infraestrutura de comunicação da solução de gerenciamento. Sendo assim, de um lado existem as pesquisas ligadas à aplicação de computação autonômica e propriedades self-* que sofrem com o problema da falta de aproximação dos modelos de alto nível com a infraestrutura de gerenciamento, e do outro lado existem as que aplicam P2P e que sofrem com o problema oposto. Dado o cenário descrito acima...

Gerenciamento de redes fortemente distribuído utilizando a tecnologia P2P; Strongly distributed network management using p2p technology

Melchiors, Cristina
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
Português
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O gerenciamento de redes é realizado seguindo diversos modelos, baseados em diferentes paradigmas. Os paradigmas tradicionais de gerenciamento compreendem o paradigma centralizado e o paradigma hierárquico fracamente distribuído. Tais paradigmas, contudo, apresentam limitações para o gerenciamento de diversas redes atuais, em virtude de fatores como o aumento em tamanho, em complexidade e em heterogeneidade destas redes. Em adição a estes fatores, existem atualmente contextos de rede que, por apresentarem certas peculiaridades, não podem ser gerenciados de modo apropriado por tais modelos. Estas limitações e requisitos diferenciados encontrados nas redes atuais trazem a necessidade do emprego de modelos de gerenciamento inovadores, baseados nos paradigmas fortemente distribuídos. Neste contexto, uma tecnologia que se mostra promissora para o desenvolvimento de um modelo de gerenciamento com tais características é a tecnologia peer-to-peer (P2P). Esta Tese versa sobre estes tópicos. Discute, como primeiro objetivo, as limitações dos modelos tradicionais para o gerenciamento de contextos modernos de rede, isto é, contextos de redes atuais que possuem particularidades distintas e, com isto, demandam requisitos de gerenciamento específicos...

Slowing down to speed up : protecting users against massive attacks in content distribution systems; Atrasar para aprimorar : protegendo usuários contra ataques massivos em sistemas de distribuição de conteúdo

Santos, Flávio Roberto
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
Português
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The Internet has become a large platform where users can interact and share personal files or third-party productions. Considering the increasing demand for efficient content sharing, modern and robust content distribution systems (CDS) need to be deployed and maintained. In the context of this thesis, CDS are defined as systems used for sharing any kind of content on the Internet. Two categories of CDS are underscored as the most popular ones: file sharing and streaming systems. Peer-to-peer (P2P) architectures have emerged as a potential solution to improve content dissemination in CDS. The popularization of P2P architectures, in the context of CDS,motivated the scientific community to investigate some challenging problems, namely network topology optimization, bootstrap mechanisms, and service discovery. One particular interesting challenge, in the context of this thesis, is related to mechanisms to approximate users to their personal interests. This is important to guarantee good quality of experience (QoE) to users when searching for content. Imprecise descriptions are likely to happen due to different users’ opinion or malicious behavior. Substantial research has been carried out to fight content pollution in CDS. Proposed approaches try to identify and isolate suspicious content after publication. The rationale is to build a base of knowledge about polluters and fake content. However...

Um sistema P2P adaptável a diferentes contextos de utilização

Bompastor, Bruno; Sousa, Pedro
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2010 Português
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No mundo actual em que vivemos tudo e todos estão conectados por uma rede global denominada Internet, onde as aplicações P2P proliferam. Com a crescente evolução da Internet tem-se vindo a observar um aumento na utilização de soluções P2P, que devido à sua imprevisibilidade trazem fortes problemas para os fornecedores de serviços (e.g. ISPs). Este artigo apresentará um sistema P2P baseado no protocolo BitTorrent de fácil integração na rede Internet através da sua capacidade de adaptação a diferentes contextos de utilização. Esta integração será alcançada recorrendo a vários mecanismos e estratégias implementadas no sistema desenvolvido. A arquitectura a desenvolver será avaliada e testada com o auxilio da ferramenta de simulação NS-2, com o objectivo de testar os mecanismos propostos e analisar os resultados obtidos.

A framework for highly reconfigurable P2P trackers

Sousa, Pedro
Fonte: Croatian Communications and Information Society (CCIS) Publicador: Croatian Communications and Information Society (CCIS)
Tipo: Artigo de Revista Científica
Publicado em /12/2013 Português
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The increasing use of Peer to Peer (P2P) applications, usually ruled by selfish behaviors, is posing new challenges to the research community. As contributions of this work we firstly devise a general framework underpinning the development of highly reconfigurable P2P trackers. Following that, a novel tracker architecture is proposed and several illustrative and enhanced tracker configurations are described. As result, the devised solution turns possible that flexible, programmable and adaptive peer selection mechanisms can be introduced at the P2P application level. The proposed solution assumes the general framework of one of the most popular P2P solutions, in this case a BitTorrent-like approach. As illustrative examples of the proposed framework capabilities, several straightforward and easy to deploy tracker configuration examples are presented, including methods for qualitative differentiation of swarm peers and advanced P2P Traffic Engineering mechanisms fostering the collaboration efforts between ISPs and P2P applications. Both the framework and the devised tracker configurations are validated resorting to simulation experiments.

Inteligência estratégica antecipativa coletiva e crowdfunding: aplicação do método L.E.SCAnning em empresa social de economia peer-to-peer (P2P)

Blanck,Mery; Janissek-Muniz,Raquel
Fonte: Departamento de Administração da Faculdade de Economia, Administração e Contabilidade da Universidade de São Paulo Publicador: Departamento de Administração da Faculdade de Economia, Administração e Contabilidade da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2014 Português
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Neste artigo, apresentam-se os resultados de pesquisa qualitativa em que se objetivou investigar a aplicabilidade do método L.E.SCAnning em empresas sociais de economia peer-to-peer (P2P). A motivação partiu da ideia de a autossustentabilidade ser, a longo prazo, um dos maiores desafios das organizações, especialmente aquelas lastreadas na economia social, dentre elas, as empresas P2P. No entanto, empresas sociais são potencialmente negócios dinâmicos e progressistas com os quais o mercado empresarial poderia aprender, uma vez que experimentam e inovam. Partindo exatamente desse espírito inovador, muitas empresas sociais voltaram-se para o modelo crowdfunding de economia P2P, que se configura como tendência emergente de organização colaborativa de recursos na Web. Sob esse prisma, um dos novos desenvolvimentos em gestão que se aplicam à atividade de organizações com enfoque sistêmico é a prática da Inteligência Estratégica Antecipativa Coletiva (IEAc). Nesse sentido, no estudo de caso investigou-se a empresa social francesa Babyloan para compreender de que maneira a organização busca, monitora e utiliza a informação captada do meio externo para sua atuação, prototipando, com base nesse diagnóstico, a aplicação de um ciclo do método L.E.SCAnning. Os resultados deste estudo sugerem que o entendimento pragmático do cenário externo...

Efficient Semantic-based Content Search in P2P Network

Shen, Heng Tao; Shu, Yan Feng; Yu, Bei
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Artigo de Revista Científica Formato: 115972 bytes; application/pdf
Português
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Most existing Peer-to-Peer (P2P) systems support only title-based searches and are limited in functionality when compared to today’s search engines. In this paper, we present the design of a distributed P2P information sharing system that supports semantic-based content searches of relevant documents. First, we propose a general and extensible framework for searching similar documents in P2P network. The framework is based on the novel concept of Hierarchical Summary Structure. Second, based on the framework, we develop our efficient document searching system, by effectively summarizing and maintaining all documents within the network with different granularity. Finally, an experimental study is conducted on a real P2P prototype, and a large-scale network is further simulated. The results show the effectiveness, efficiency and scalability of the proposed system.; Singapore-MIT Alliance (SMA)

Uma arquitetura P2P baseada na hierarquia do endereçamento IP com roteamento unificado

Pinheiro, Marcos Cesar Madruga Alves
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Elétrica; Automação e Sistemas; Engenharia de Computação; Telecomunicações Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Elétrica; Automação e Sistemas; Engenharia de Computação; Telecomunicações
Tipo: Tese de Doutorado Formato: application/pdf
Português
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There are some approaches that take advantage of unused computational resources in the Internet nodes - users´ machines. In the last years , the peer-to-peer networks (P2P) have gaining a momentum mainly due to its support for scalability and fault tolerance. However, current P2P architectures present some problems such as nodes overhead due to messages routing, a great amount of nodes reconfigurations when the network topology changes, routing traffic inside a specific network even when the traffic is not directed to a machine of this network, and the lack of a proximity relationship among the P2P nodes and the proximity of these nodes in the IP network. Although some architectures use the information about the nodes distance in the IP network, they use methods that require dynamic information. In this work we propose a P2P architecture to fix the problems afore mentioned. It is composed of three parts. The first part consists of a basic P2P architecture, called SGrid, which maintains a relationship of nodes in the P2P network with their position in the IP network. Its assigns adjacent key regions to nodes of a same organization. The second part is a protocol called NATal (Routing and NAT application layer) that extends the basic architecture in order to remove from the nodes the responsibility of routing messages. The third part consists of a special kind of node...

Segurança da informação em redes peer-to-peer (P2P)

Fonte: Universidade Federal de Lavras Publicador: Universidade Federal de Lavras
Tipo: Trabalho de Conclusão de Curso
Português
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The great progress in the areas of telecommunications and computer networks, combined with the large reduction in cost of computer resources, led to the proliferation of networks for all segments of society. In this context, a class of systems and applications that use distributed resources to perform critical functions in a decentralized way, P2P applications. With the expansion of interest in use of P2P applications, especially in corporate environments, the security of such system has been a major constraint to their use france. Accordingly, the objective of this review was on two themes that cross has received the attention of both the scientific community and industry: Peer-to-Peer (P2P) and Information Security. At the end of the review you can see that the system for P2P networks are very attractive and widely circulated for several reasons. Systems are scalable, or do not have a central point of failure or bottleneck in the form of a central server, networks that are better to resist intentional attacks such as denial of service and has the power to attract a large number of users in function of the benefits offered by the community, without however, giving the autonomy of its participants. However, despite the best resist intentional attacks are susceptible to security flaws or show some kind of vulnerability. Therefore...

QoE-driven user-centric VoD services in urban multi-homed P2P-based vehicular networks

Xu, Changqiao; Zhao, Futao; Guan, Jianfeng; Zhang, Hongke; Muntean, Gabriel-Miro
Fonte: IEEE Computer Society Publicador: IEEE Computer Society
Tipo: info:eu-repo/semantics/article; all_ul_research; ul_published_reviewed
Português
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peer-reviewed; Recently many cities around the world have witnessed large scale deployment of terrestrial broadcasting mobile TV to vehicles. This service is similar to the cable or satellite television already watched at home and user-centric interactive mobile Video-on-Demand (VoD) over urban vehicular networks is in fact expected. However providing this new service with focus on user Quality of Experience (QoE) constitutes a significant challenge. This paper introduces a QoE-driven User-centric solution for VoD services in urban vehicular network environments (QUVoD). QUVoD relies on a multi-homed hierarchical peer-topeer (P2P) and vehicular ad-hoc network (VANET) architecture. Vehicles construct a low layer VANET via WAVE interfaces and also form an upper layer P2P Chord overlay on top of a cellular network via 4G interfaces. A novel grouping-based storage strategy is proposed which distributes uniformly the video segments along the Chord overlay, reducing segment seeking traffic, while also enabling load-balancing. A novel segment seeking and multipath delivery scheme is also introduced which achieves high lookup success rate and very good video data delivery efficiency. Furthermore, a new speculation-based prefetching strategy is proposed...

P2P object tracking in the internet of things

Wu, Y.; Sheng, Q.; Ranasinghe, D.
Fonte: IEEE; USA Publicador: IEEE; USA
Tipo: Conference paper
Publicado em //2011 Português
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With recent advances in technologies such as radio-frequency identification (RFID) and new standards such as the electronic product code (EPC), large-scale traceability is emerging as a key differentiator in a wide range of enterprise applications (e.g., counterfeit prevention, product recalls, and pilferage reduction). Such traceability applications often need to access data collected by individual enterprises in a distributed environment. Traditional centralized approaches (e.g., data ware-housing) are not feasible for these applications due to their unique characteristics such as large volume of data and sovereignty of the participants. In this paper, we describe an approach that enables applications to share traceability data across independent enterprises in a pure Peer-to-Peer (P2P) fashion. Data are stored in local repositories of participants and indexed in the network based on structured P2P overlays. In particular, we present a generic approach for efficiently indexing and locating individual objects in large, distributed traceable networks, most notably, in the emerging environment of the Internet of Things. The results from extensive experiments show that our approach scales well in both data volume and network size.; Yanbo Wu...

Analysis of searching mechanisms in hierarchical p2p based overlay networks

Martínez-Yelmo, Isaías; Cuevas, Rubén; Guerrero, Carmen; Mauthe, Andreas
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: Conferência ou Objeto de Conferência Formato: application/pdf
Publicado em /06/2007 Português
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This work presents a study of searching mechanisms in Peer-to-Peer (p2p) networks. The aim of this research line is to analyse cross-searching mechanisms that will allow the hierarchical interconnection of p2p networks. A set of relevant metrics for interconnection scenarios are defined to evaluate scalability, robustness and routing latency.; This work has been partially supported by the European Union under the IST Content (FP6-2006-IST-507295) project and by the Madrid regional government under the Biogridnet (CAM, S-0505/TIC-0101) project.; Proceedings of: The 6th Annual Mediterranean Ad Hoc Networking Workshop (Med Hoc Net 2007. (Corfu, Greece), June 2007

Secure content access and replication in pure P2P networks

Palomar, Esther; Estévez-Tapiador, Juan M.; Hernández-Castro, Julio C.; Ribagorda, Arturo
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em /02/2008 Português
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Despite the advantages offered by pure Peer-to-Peer (P2P) networks (e.g. robustness and fault tolerance), a crucial requirement is to guarantee basic security properties, such as content authenticity and integrity, as well as to enforce appropriate access control policies. These mechanisms would pave the way for new models in which content providers can exert some control over the replication and file sharing process. However, the extremely decentralized nature of these environments makes impossible to apply classic solutions that rely on some kind of fixed infrastructure, typically in the form of on-line trusted third parties (TTP). In this paper, we introduce a suite of protocols for content authentication and access control in pure P2P networks based on attribute certificates that does not rely on the existence of a public key infrastructure (PKI), privilege management infrastructure (PMI), or any other form of centralized authority. We provide an analysis concerning the efficiency (computational effort and communication overhead) and the security of our proposal.; 14 pages, 8 figures.-- A preliminary version of this work appeared in the Proceedings of the 6th International Conference on P2P Computing (P2P 2006, Cambridge, UK, Oct 2-4...

Peer-to-peer television for the IP multimedia subsystem

Bikfalvi, Alexandru
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: Tese de Doutorado Formato: application/pdf
Português
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Peer-to-peer (P2P) video streaming has generated a significant amount of interest in both the research community and the industry, which find it a cost-effective solution to the user scalability problem. However, despite the success of Internet-based applications, the adoption has been limited for commercial services, such as Internet Protocol Television (IPTV). With the advent of the next-generation-networks (NGN) based on the IP Multimedia Subsystem (IMS), advocating for an open and inter-operable architecture, P2P emerges as a possible alternative in situations where the traditional mechanisms are not possible or economically feasible. This work proposes a P2P IPTV architecture for an IMS-based NGN, called P2PTV, which allows one or more service providers to use a common P2P infrastructure for streaming the TV channels to their subscribers. Instead of using servers, we rely on the uploading capabilities of the user equipments, like set-top boxes, located at the customers’ premise. We comply with the existing IMS and IPTV standards from the 3rd Generation Partnership Project (3GPP) and the Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN) bodies, where a centralized P2PTV application server (AS) manages the customer access to the service and the peer participation. Because watching TV is a complex and demanding user activity...

Supporting mobility in an IMS-based P2P IPTV service: A proactive context transfer mechanism

Vidal Fernández, Iván; García-Reinoso, Jaime; Oliva Delgado, Antonio de la; Bikfalvi, Alex; Soto Campos, Ignacio
Fonte: Elsevier Publicador: Elsevier
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/article
Publicado em /09/2010 Português
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In recent years, IPTV has received an increasing amount of interest from the industry, commercial providers and the research community, alike. In this context, standardization bodies, such as ETSI and ITU-T, are specifying the architecture of IPTV systems based on IP multicast. An interesting alternative to support the IPTV service delivery relies on the Peer-to-Peer (P2P) paradigm to distribute and push the streaming effort towards the network edge. However, while P2P IPTV was studied in fixed access technologies, there has been little attention paid to the implications arising in mobile environments. One of these involves the service handover when the user moves to a different network. By analyzing previous work from the perspective of an IPTV service, we concluded that a proactive approach is necessary for the handling of inter-network handovers. In this paper, we propose a new general handover mechanism for the IP Multimedia Subsystem (IMS), while studying its applicability to a P2P IPTV service. Our solution, called proactive context transfer service, incorporates the existing IEEE 802.21 technology in order to minimize the handover delay. The proposal is validated by comparing it against solutions derived from previous work.; This article has been partially granted by the Spanish MEC through the CONPARTE project (TEC2007–67966-C03–03/TCM) and by the Madrid Community through the MEDIANET project (S-2009/TIC-1468).

Multiple description image and video coding for P2P transmissions

Quaresma, Marisa Raposo
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2009 Português
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Peer-to-Peer (P2P) media streaming is, nowadays, a very attractive topic due to the bandwidth available to serve demanding content scales. A key challenge, however, is making content distribution robust to peer transience. Multiple description coding (MDC) has, indeed, proven to be very effective with problems concerning the packets’ losses, since it generates several descriptions and may reconstruct the original information with any number of descriptions that may reach the decoder. Therefore multiple descriptions may be effective for robust peer-to-peer media streaming. In this dissertation, it will not only be showed that, but also that varying the redundancy level of description on the fly may lead to a better performance than the one obtained without varying this parameter. Besides that, it is shown, as well, that varying the Bitrate on the fly outperforms the redundancy on it. Furthermore, the redundancy and the Bitrate were varied simultaneously. Thus, it is shown that this variation is more efficient when the packet loss is high. The experiments reported above were done using an experimental test bed developed for this purpose at the NMCG lab of the University of Beira Interior. It was also used the REGPROT, a video encoder developed by our research team...

Exploiting semantic locality to improve peer-to-peer search mechanisms

Sharan, Ajitabh
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado Formato: 359640 bytes; application/pdf
Português
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A Peer-to-Peer(P2P) network is the most popular technology in file sharing today. With the advent of various commercial and non-commercial applications like KaZaA, Gnutella, a P2P network has exercised its growth and popularity to the maximum. Every node (peer) in a P2P network acts as both a client and a server for other peers. A search in P2P network is performed as a query relayed between peers until the peer that contains the searched data is found. Huge data size, complex management requirements, dynamic network conditions and distributed systems are some of the difficult challenges a P2P system faces while performing a search. Moreover, a blind and uninformed search leads to performance degradation and wastage of resources. To address these weaknesses, techniques like Distributed Hash Table (DHT) has been proposed to place a tight constraint on the node placement. However, it does not considers semantic significance of the data. We propose a new peer to peer search protocol that identities locality in a P2P network to mitigate the complexity in data searching. Locality is a logical semantic categorization of a group of peers sharing common data. With the help of locality information, our search model offers more informed and intelligent search for different queries. To evaluate the effectiveness of our model we propose a new P2P search protocol - LocalChord. LocalChord relies on Chord and demonstrates potential of our proposed locality scheme by re-modelling Chord as a Chord of sub-chords.

Inteligência estratégica antecipativa coletiva e crowdfunding: aplicação do método L.E.SCAnning em empresa social de economia peer-to-peer (P2P); Inteligencia estratégica anticipativa colectiva y crowdfunding: aplicación del método L.E.SCAnning en empresa social de economía peer-to-peer (P2P); Strategic environmental scanning and crowdfunding: applying the L.E.SCAnning© method to a social enterprise of the peer-to-peer (P2P) economy

Blanck, Mery; Janissek-Muniz, Raquel
Fonte: Universidade de São Paulo. Faculdade de Economia, Administração e Contabilidade Publicador: Universidade de São Paulo. Faculdade de Economia, Administração e Contabilidade
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 01/03/2014 Português
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This paper presents the results of a qualitative study that investigated the applicability of L.E.SCAnning method to social economy enterprises peer-to-peer (P2P). The motivation came from the idea of being long-term self-sustainability one of the biggest challenges to be faced by organizations; especially those backed by the social economy, among them, the P2P companies. But social enterprises are potentially dynamic and progressive business with which the business market could learn, as experimental and innovative. From exactly this spirit of innovation, many social enterprises have turned to the crowdfunding P2P model of economy, which is configured as an emerging trend in collaborative organization of resources on Web. In this light, one of the new developments in management that is applicable to organizations with systemic approach is the practice of Strategic Intelligence, particularly the Anticipative and Collective Strategic Intelligence Method (IEAc). Thus, this case study investigated the French social enterprise Babyloan to understand how the organization seeks, monitors and utilizes the information captured from the external environment to its performance, prototyping, based on this diagnosis, the application of one cycle of L.E.SCAnning method. The results suggest that the pragmatic understanding of the external environment through IEAc favors decisions that bring a mark of entrepreneurship and innovation...