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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
Relevância na Pesquisa
68.987446%
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...

Comparação analítica dos esquemas de autenticação em sistemas P2P de live streaming; Comparative analisys of authentication schemes in P2P live streaming

Coelho, Rafael Vieira
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
68.634546%
As aplicações de live streaming em redes P2P têm grande potencial de crescimento, em popularidade e qualidade, mas são potencialmente vulneráveis ao ataque de poluição de conteúdo. Tal ataque corresponde a qualquer adulteração de áudio e/ou vídeo na mídia transmitida buscando ludibriar espectadores. A autenticação de blocos do fluxo de dados contínuo (stream) permite a detecção de conteúdo poluído e a possível identificação de pares maliciosos na rede P2P. A literatura contém diversas propostas de autenticação baseadas em assinatura digital leve e em amortização de assinatura digital. O presente trabalho, como nenhum anterior, compara tanto os esquemas de assinatura leve quanto os de amortização sob diferentes perspectivas de qualidade de transmissão (vídeos convencionais e de alta definição) em redes P2P de live streaming através da formularização analítica dos mesmos. Para isto, é feita uma comparação quantitativa de sobrecargas e nível de segurança, observando fenômenos e identificando desafios de pesquisa que precisarão ser vencidos. Particularmente, para avaliar a viabilidade dos esquemas, foi definido um coeficiente que leva em consideração o tempo total de transmissão e o custo computacional proporcionado pelo esquema estudado. Como uma das conclusões inéditas dessa análise...

Proposta de arquitetura adaptativa para transmissão multidestinatária e ao vivo de vídeo escalável em rede par-a-par; An adaptive architecture for live streaming of scalable video over p2p network

Dias, Bernardo Vergne
Fonte: Universidade de Brasília Publicador: Universidade de Brasília
Tipo: Dissertação
Português
Relevância na Pesquisa
48.238066%
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Elétrica, 2012.; A distribuição de fluxo contínuo de vídeo (video streaming) é, atualmente, uma das aplicações de maior sucesso na Internet, sendo as redes par-a-par (P2P, Peer-to-Peer), baseadas em princípios como a escalabilidade e o compartilhamento de recursos, uma das opções importantes para contribuir para a solução de diversos gargalos decorrentes do emprego da tradicional arquitetura cliente-servidor, comumente presente na Internet. Por outro lado, esquemas de codificação de vídeo têm sido recentemente propostos, que permitem o ajuste entre a disponibilidade de recursos (banda) de rede e a quantidade de informação (camadas) sendo enviada para transmissão. Dentre tais esquemas, destaca-se o H.264 SVC (Scalable Video Coding), normatizado pela ITU-T (International Telecommunication Union). Dessa forma, o trabalho inicia-se com a apresentação de conceitos relativos à codificação escalável de vídeo bem como sobre alternativas relativas à distribuição de vídeo sobre redes P2P. Adicionalmente, o trabalho discute alternativas de protocolos de controle de congestionamento multidestinatário...

Exploring a QoS Driven Scheduling Approach for Peer-to-Peer Live Streaming Systems with Network Coding

Cui, Laizhong; Lu, Nan; Chen, Fu
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
48.145117%
Most large-scale peer-to-peer (P2P) live streaming systems use mesh to organize peers and leverage pull scheduling to transmit packets for providing robustness in dynamic environment. The pull scheduling brings large packet delay. Network coding makes the push scheduling feasible in mesh P2P live streaming and improves the efficiency. However, it may also introduce some extra delays and coding computational overhead. To improve the packet delay, streaming quality, and coding overhead, in this paper are as follows. we propose a QoS driven push scheduling approach. The main contributions of this paper are: (i) We introduce a new network coding method to increase the content diversity and reduce the complexity of scheduling; (ii) we formulate the push scheduling as an optimization problem and transform it to a min-cost flow problem for solving it in polynomial time; (iii) we propose a push scheduling algorithm to reduce the coding overhead and do extensive experiments to validate the effectiveness of our approach. Compared with previous approaches, the simulation results demonstrate that packet delay, continuity index, and coding ratio of our system can be significantly improved, especially in dynamic environments.

A Study of Traffic Locality and Reliability in Peer-to-Peer Video Streaming Applications

ZHANG, XIANGYANG
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
48.682207%
The past decade has witnessed tremendous growth of peer-to-peer (P2P) video streaming applications on the Internet. For these applications, playback smoothness and timeliness are the two most important aspects of users' viewing experiences, whereas the amount of traffic is Internet service providers' main concern. According to the playback delay, video streaming can be classified into on-demand streaming, live streaming, and interactive streaming. P2P live streaming applications typically have an arbitrary number of users, tens of seconds of playback delay, and a high packet delivery rate, but their heavy traffic incurs great financial expenditure and threatens the quality of other services. Interactive streaming applications usually have a small group size, several hundreds of milliseconds of playback delay, and reasonable traffic volume, but cannot achieve a high packet delivery rate. The goal of this thesis is to study traffic locality and reliable delivery of packets in large-scale live streaming and small-scale interactive streaming applications, while keeping the playback delay well below the targeted applications' limits. For P2P live streaming applications, we first identify "typical" schemes from existing P2P live streaming schemes...

Detection of encrypted traffic generated by peer-to-peer live streaming applications using deep packet inspection

Esteves, André Filipe Ferreira
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2011 Português
Relevância na Pesquisa
47.854883%
The number of applications using the peer-to-peer (P2P) networking paradigm and their popularity has substantially grown over the last decade. They evolved from the le-sharing applications to media streaming ones. Nowadays these applications commonly encrypt the communication contents or employ protocol obfuscation techniques. In this dissertation, it was conducted an investigation to identify encrypted traf c ows generated by three of the most popular P2P live streaming applications: TVUPlayer, Livestation and GoalBit. For this work, a test-bed that could simulate a near real scenario was created, and traf c was captured from a great variety of applications. The method proposed resort to Deep Packet Inspection (DPI), so we needed to analyse the payload of the packets in order to nd repeated patterns, that later were used to create a set of SNORT rules that can be used to detect key network packets generated by these applications. The method was evaluated experimentally on the test-bed created for that purpose, being shown that its accuracy is of 97% for GoalBit.; Fundação para a Ciência e a Tecnologia (FCT)

Live Streaming y Video On Demand de contenido académico producido en la PUCP

Fonte: RedCLARA Publicador: RedCLARA
Tipo: Artigo de Revista Científica Formato: PDF
Português
Relevância na Pesquisa
57.99209%
Las universidades requieren cada vez más que sus actividades académicas y de investigación sean difundidas a un mayor número de usuarios. Internet nos permite que el intercambio de información sea en tiempo real, lo que facilita que los eventos sean transmitidos en vivo, así como bajo demanda cada vez que el usuario lo solicite. Las tecnologías streaming siguen evolucionando, adaptándose a los recursos de red y nuevos dispositivos finales, por ello desplegar este tipo de servicios requiere considerar múltiples factores como ancho de banda, consumo de recursos, servidores y protocolos de transmisión, dispositivos de reproducción, entre otros. El presente trabajo tiene por objetivo analizar las diferentes tecnologías de streaming disponibles e implementar una solución que garantice ancho de banda y compatibilidad con la mayor cantidad de dispositivos.

Supporting Seamless Mobility for P2P Live Streaming

Kim, Eunsam; Kim, Sangjin; Lee, Choonhwa
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
48.23929%
With advent of various mobile devices with powerful networking and computing capabilities, the users' demand to enjoy live video streaming services such as IPTV with mobile devices has been increasing rapidly. However, it is challenging to get over the degradation of service quality due to data loss caused by the handover. Although many handover schemes were proposed at protocol layers below the application layer, they inherently suffer from data loss while the network is being disconnected during the handover. We therefore propose an efficient application-layer handover scheme to support seamless mobility for P2P live streaming. By simulation experiments, we show that the P2P live streaming system with our proposed handover scheme can improve the playback continuity significantly compared to that without our scheme.

A simple analysis on P2P streaming with peer playback lags

Zhao, Y.; Shen, H.
Fonte: IEEE; USA Publicador: IEEE; USA
Tipo: Conference paper
Publicado em //2011 Português
Relevância na Pesquisa
58.145117%
Nowadays, mesh-based live streaming on P2P network is becoming more and more popular because of its scalability, robustness and no additional infrastructure requirement (e.g. CoolStreaming, PPlive, PPstream, Gridmedia). How to design a high fluency and small delay system is a challenge task. In this paper we analyze the impact of playback lags between peers on the playback fluency via a simple stochastic model. For every position in arbitrary peer’s buffer, we calculate its probability of containing the corresponding chunk, which can indicate the fluency of a peer’s playback on the video. Through our analysis and simulation, we get insights into playback lags and some useful tips for designing a real P2P live streaming system more effective.; Yang Zhao and Hong Shen

Congestion Control for P2P Live Streaming

Efthymiopoulos, Nikolaos; Christakidis, Athanasios; Efthymiopoulou, Maria; Corazza, Loris; Denazis, Spyros
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/10/2015 Português
Relevância na Pesquisa
48.23929%
In recent years, research efforts tried to exploit peer-to-peer (P2P) systems in order to provide Live Streaming (LS) and Video-on-Demand (VoD) services. Most of these research efforts focus on the development of distributed P2P block schedulers for content exchange among the participating peers and on the characteristics of the overlay graph (P2P overlay) that interconnects the set of these peers. Currently, researchers try to combine peer-to-peer systems with cloud infrastructures. They developed monitoring and control architectures that use resources from the cloud in order to enhance QoS and achieve an attractive trade-off between stability and low cost operation. However, there is a lack of research effort on the congestion control of these systems and the existing congestion control architectures are not suitable for P2P live streaming traffic (small sequential non persistent traffic towards multiple network locations). This paper proposes a P2P live streaming traffic aware congestion control protocol that: i) is capable to manage sequential traffic heading to multiple network destinations , ii) efficiently exploits the available bandwidth, iii) accurately measures the idle peer resources, iv) avoids network congestion, and v) is friendly to traditional TCP generated traffic. The proposed P2P congestion control has been implemented...

Peer-to-Peer Live Streaming and Video On Demand Design Issues and its Challenges

K, Hareesh.; H, Manjaiah D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 29/11/2011 Português
Relevância na Pesquisa
48.145117%
Peer-to-Peer Live streaming and Video on Demand is the most popular media applications over the Internet in recent years. These systems reduce the load on the server and provide a scalable content distribution. A new paradigm of P2P network collaborates to build large distributed video applications on existing networks .But, the problem of designing the system are at par with the P2P media streaming, live and Video on demand systems. Hence a comprehensive design comparison is needed to build such kind of system architecture. Therefore, in this paper we elaborately studied the traditional approaches for P2P streaming architectures, and its critical design issues, as well as practicable challenges. Thus, our studies in this paper clearly point the tangible design issues and its challenges, and other intangible issues for providing P2P VoD services.; Comment: International Journal of Peer to Peer Networks (IJP2P), Vol.2, No.4, October 2011

Modeling and Performance Analysis of Pull-Based Live Streaming Schemes in Peer-to-Peer Network

Zhang, Jianwei; Xing, Wei; Wang, Yongchao; Lu, Dongming
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 16/02/2013 Português
Relevância na Pesquisa
48.30519%
Recent years mesh-based Peer-to-Peer live streaming has become a promising way for service providers to offer high-quality live video streaming service to Internet users. In this paper, we make a detailed study on modeling and performance analysis of the pull-based P2P streaming systems. We establish the analytical framework for the pull-based streaming schemes in P2P network, give accurate models of the chunk selection and peer selection strategies, and organize them into three categories, i.e., the chunk first scheme, the peer first scheme and the epidemic scheme. Through numerical performance evaluation, the impacts of some important parameters, such as size of neighbor set, reply number, buffer size and so on are investigated. For the peer first and chunk first scheme, we show that the pull-based schemes do not perform as well as the push-based schemes when peers are limited to reply only one request in each time slot. When the reply number increases, the pull-based streaming schemes will reach close to optimal playout probability. As to the pull-based epidemic scheme, we find it has unexpected poor performance, which is significantly different from the push-based epidemic scheme. Therefore we propose a simple, efficient and easily deployed push-pull scheme which can significantly improve the playout probability.

On Using Seeders for P2P Live Streaming

Mathieu, Fabien
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/04/2011 Português
Relevância na Pesquisa
47.87913%
Seeders (peers that do not request anything but contribute to the system) are a powerful concept in peer-to-peer (P2P). They allow to leverage the capacities of a P2P system. While seeding is a natural idea for filesharing or video-on-demand applications, it seems somehow counter-intuitive in the context of live streaming. This paper aims at describing the feasibility and performance of P2P live seeding. After a formal definition of "live seeding" and efficiency, we consider the theoretical performance of systems where the overhead is neglected. We then propose a linear overhead model and extend the results for this model, for a single seeder and for a set of seeders as well (it is not always possible to perfectly aggregate individual efficiencies in a given system).

Size Does Matter (in P2P Live Streaming)

Hegde, Nidhi; Mathieu, Fabien; Perino, Diego
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/09/2009 Português
Relevância na Pesquisa
48.007915%
Optimal dissemination schemes have previously been studied for peer-to-peer live streaming applications. Live streaming being a delay-sensitive application, fine tuning of dissemination parameters is crucial. In this report, we investigate optimal sizing of chunks, the units of data exchange, and probe sets, the number peers a given node probes before transmitting chunks. Chunk size can have significant impact on diffusion rate (chunk miss ratio), diffusion delay, and overhead. The size of the probe set can also affect these metrics, primarily through the choices available for chunk dissemination. We perform extensive simulations on the so-called random-peer, latest-useful dissemination scheme. Our results show that size does matter, with the optimal size being not too small in both cases.

On Resource Aware Algorithms in Epidemic Live Streaming

Mathieu, Fabien; Perino, Diego
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/09/2009 Português
Relevância na Pesquisa
47.631924%
Epidemic-style diffusion schemes have been previously proposed for achieving peer-to-peer live streaming. Their performance trade-offs have been deeply analyzed for homogeneous systems, where all peers have the same upload capacity. However, epidemic schemes designed for heterogeneous systems have not been completely understood yet. In this report we focus on the peer selection process and propose a generic model that encompasses a large class of algorithms. The process is modeled as a combination of two functions, an aware one and an agnostic one. By means of simulations, we analyze the awareness-agnostism trade-offs on the peer selection process and the impact of the source distribution policy in non-homogeneous networks. We highlight that the early diffusion of a given chunk is crucial for its overall diffusion performance, and a fairness trade-off arises between the performance of heterogeneous peers, as a function of the level of awareness.

Heterogeneity in Distributed Live Streaming: Blessing or Curse?

Mathieu, Fabien
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/09/2009 Português
Relevância na Pesquisa
48.23929%
Distributed live streaming has brought a lot of interest in the past few years. In the homogeneous case (all nodes having the same capacity), many algorithms have been proposed, which have been proven almost optimal or optimal. On the other hand, the performance of heterogeneous systems is not completely understood yet. In this paper, we investigate the impact of heterogeneity on the achievable delay of chunk-based live streaming systems. We propose several models for taking the atomicity of a chunk into account. For all these models, when considering the transmission of a single chunk, heterogeneity is indeed a ``blessing'', in the sense that the achievable delay is always faster than an equivalent homogeneous system. But for a stream of chunks, we show that it can be a ``curse'': there is systems where the achievable delay can be arbitrary greater compared to equivalent homogeneous systems. However, if the system is slightly bandwidth-overprovisioned, optimal single chunk diffusion schemes can be adapted to a stream of chunks, leading to near-optimal, faster than homogeneous systems, heterogeneous live streaming systems.

Crowdsourced Live Streaming over the Cloud

Chen, Fei; Zhang, Cong; Wang, Feng; Liu, Jiangchuan
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/02/2015 Português
Relevância na Pesquisa
48.39567%
Empowered by today's rich tools for media generation and distribution, and the convenient Internet access, crowdsourced streaming generalizes the single-source streaming paradigm by including massive contributors for a video channel. It calls a joint optimization along the path from crowdsourcers, through streaming servers, to the end-users to minimize the overall latency. The dynamics of the video sources, together with the globalized request demands and the high computation demand from each sourcer, make crowdsourced live streaming challenging even with powerful support from modern cloud computing. In this paper, we present a generic framework that facilitates a cost-effective cloud service for crowdsourced live streaming. Through adaptively leasing, the cloud servers can be provisioned in a fine granularity to accommodate geo-distributed video crowdsourcers. We present an optimal solution to deal with service migration among cloud instances of diverse lease prices. It also addresses the location impact to the streaming quality. To understand the performance of the proposed strategies in the realworld, we have built a prototype system running over the planetlab and the Amazon/Microsoft Cloud. Our extensive experiments demonstrate that the effectiveness of our solution in terms of deployment cost and streaming quality.

On Crowdsourced Interactive Live Streaming: A Twitch.TV-Based Measurement Study

Zhang, Cong; Liu, Jiangchuan
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
48.442104%
Empowered by today's rich tools for media generation and collaborative production, the multimedia service paradigm is shifting from the conventional single source, to multi-source, to many sources, and now toward {\em crowdsource}. Such crowdsourced live streaming platforms as Twitch.tv allow general users to broadcast their content to massive viewers, thereby greatly expanding the content and user bases. The resources available for these non-professional broadcasters however are limited and unstable, which potentially impair the streaming quality and viewers' experience. The diverse live interactions among the broadcasters and viewers can further aggravate the problem. In this paper, we present an initial investigation on the modern crowdsourced live streaming systems. Taking Twitch as a representative, we outline their inside architecture using both crawled data and captured traffic of local broadcasters/viewers. Closely examining the access data collected in a two-month period, we reveal that the view patterns are determined by both events and broadcasters' sources. Our measurements explore the unique source- and event-driven views, showing that the current delay strategy on the viewer's side substantially impacts the viewers' interactive experience...

Fetching Strategy in the Startup Stage of p2p Live Streaming

Li, Chunxi; Chen, Changjia
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/10/2008 Português
Relevância na Pesquisa
47.631924%
A protocol named Threshold Bipolar (TB) is proposed as a fetching strategy at the startup stage of p2p live streaming systems. In this protocol, chunks are fetched consecutively from buffer head at the beginning. After the buffer is filled into a threshold, chunks at the buffer tail will be fetched first while keeping the contiguously filled part in the buffer above the threshold even when the buffer is drained at a playback rate. High download rate, small startup latency and natural strategy handover can be reached at the same time by this protocol. Important parameters in this protocol are identified. The buffer progress under this protocol is then expressed as piecewise lines specified by those parameters. Startup traces of peers measured from PPLive are studied to show the real performance of TB protocol in a real system. A simple design model of TB protocol is proposed to reveal important considerations in a practical design.; Comment: 9 pages, 11 figures

Algorithms for Constructing Overlay Networks For Live Streaming

Andreev, Konstantin; Maggs, Bruce M.; Meyerson, Adam; Saks, Jevan; Sitaraman, Ramesh K.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 19/09/2011 Português
Relevância na Pesquisa
48.16588%
We present a polynomial time approximation algorithm for constructing an overlay multicast network for streaming live media events over the Internet. The class of overlay networks constructed by our algorithm include networks used by Akamai Technologies to deliver live media events to a global audience with high fidelity. We construct networks consisting of three stages of nodes. The nodes in the first stage are the entry points that act as sources for the live streams. Each source forwards each of its streams to one or more nodes in the second stage that are called reflectors. A reflector can split an incoming stream into multiple identical outgoing streams, which are then sent on to nodes in the third and final stage that act as sinks and are located in edge networks near end-users. As the packets in a stream travel from one stage to the next, some of them may be lost. A sink combines the packets from multiple instances of the same stream (by reordering packets and discarding duplicates) to form a single instance of the stream with minimal loss. Our primary contribution is an algorithm that constructs an overlay network that provably satisfies capacity and reliability constraints to within a constant factor of optimal, and minimizes cost to within a logarithmic factor of optimal. Further in the common case where only the transmission costs are minimized...