161 research outputs found
Robustness of BitTorrent-like VoD protocols
Besides server supported solutions for Video-on-demand, approaches based on distributed systems such as BitTorrent are being used due to their efficiency and high scalability. There are several protocol variants proposed in the literature, which are mainly concerned with providing mechanisms for piece selection and peer selection. In this paper, using the concept of
Design Space Analysis, we give comparisons of the performances of several BitTorrent-like Video-on-demand protocols under the assumption that other protocol variants may also enter the system
Analyzing Peer Selection Policies for BitTorrent Multimedia On-Demand Streaming Systems in Internet
The adaptation of the BitTorrent protocol to multimedia on-demand streaming
systems essentially lies on the modification of its two core algorithms, namely
the piece and the peer selection policies, respectively. Much more attention
has though been given to the piece selection policy. Within this context, this
article proposes three novel peer selection policies for the design of
BitTorrent-like protocols targeted at that type of systems: Select Balanced
Neighbour Policy (SBNP), Select Regular Neighbour Policy (SRNP), and Select
Optimistic Neighbour Policy (SONP). These proposals are validated through a
competitive analysis based on simulations which encompass a variety of
multimedia scenarios, defined in function of important characterization
parameters such as content type, content size, and client interactivity
profile. Service time, number of clients served and efficiency retrieving
coefficient are the performance metrics assessed in the analysis. The final
results mainly show that the novel proposals constitute scalable solutions that
may be considered for real project designs. Lastly, future work is included in
the conclusion of this paper.Comment: 19 PAGE
Improving BitTorrent's Peer Selection For Multimedia Content On-Demand Delivery
The great efficiency achieved by the BitTorrent protocol for the distribution
of large amounts of data inspired its adoption to provide multimedia content
on-demand delivery over the Internet. As it is not designed for this purpose,
some adjustments have been proposed in order to meet the related QoS
requirements like low startup delay and smooth playback continuity.
Accordingly, this paper introduces a BitTorrent-like proposal named as
Quota-Based Peer Selection (QBPS). This proposal is mainly based on the
adaptation of the original peer-selection policy of the BitTorrent protocol.
Its validation is achieved by means of simulations and competitive analysis.
The final results show that QBPS outperforms other recent proposals of the
literature. For instance, it achieves a throughput optimization of up to 48.0%
in low-provision capacity scenarios where users are very interactive.Comment: International Journal of Computer Networks & Communications(IJCNC)
Vol.7, No.6, November 201
Mathematical analysis of scheduling policies in peer-to-peer video streaming networks
Las redes de pares son comunidades virtuales autogestionadas, desarrolladas en la capa de aplicación sobre la infraestructura de Internet, donde los usuarios (denominados pares) comparten recursos (ancho de banda, memoria, procesamiento) para alcanzar un fin común. La distribución de video representa la aplicación más desafiante, dadas las limitaciones de ancho de banda. Existen básicamente tres servicios de video. El más simple es la descarga, donde un conjunto de servidores posee el contenido original, y los usuarios deben descargar completamente este contenido previo a su reproducción. Un segundo servicio se denomina video bajo demanda, donde los pares se unen a una red virtual siempre que inicien una solicitud de un contenido de video, e inician una descarga progresiva en lÃnea. El último servicio es video en vivo, donde el contenido de video es generado, distribuido y visualizado simultáneamente. En esta tesis se estudian aspectos de diseño para la distribución de video en vivo y bajo demanda. Se presenta un análisis matemático de estabilidad y capacidad de arquitecturas de distribución bajo demanda hÃbridas, asistidas por pares. Los pares inician descargas concurrentes de múltiples contenidos, y se desconectan cuando lo desean. Se predice la evolución esperada del sistema asumiendo proceso Poisson de arribos y egresos exponenciales, mediante un modelo determinÃstico de fluidos. Un sub-modelo de descargas secuenciales (no simultáneas) es globalmente y estructuralmente estable, independientemente de los parámetros de la red. Mediante la Ley de Little se determina el tiempo medio de residencia de usuarios en un sistema bajo demanda secuencial estacionario. Se demuestra teóricamente que la filosofÃa hÃbrida de cooperación entre pares siempre desempeña mejor que la tecnologÃa pura basada en cliente-servidor
Video-on-Demand over Internet: a survey of existing systems and solutions
Video-on-Demand is a service where movies are delivered to distributed users with low delay and free interactivity. The traditional client/server architecture experiences scalability issues to provide video streaming services, so there have been many proposals of systems, mostly based on a peer-to-peer or on a hybrid server/peer-to-peer solution, to solve this issue. This work presents a survey of the currently existing or proposed systems and solutions, based upon a subset of representative systems, and defines selection criteria allowing to classify these systems. These criteria are based on common questions such as, for example, is it video-on-demand or live streaming, is the architecture based on content delivery network, peer-to-peer or both, is the delivery overlay tree-based or mesh-based, is the system push-based or pull-based, single-stream or multi-streams, does it use data coding, and how do the clients choose their peers. Representative systems are briefly described to give a summarized overview of the proposed solutions, and four ones are analyzed in details. Finally, it is attempted to evaluate the most promising solutions for future experiments. Résumé La vidéo à la demande est un service où des films sont fournis à distance aux utilisateurs avec u
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