Testing a Cloud Provider Network for Hybrid P2P and Cloud Streaming Architectures

The number of online real-time streaming services deployed over network topologies like P2P or centralized ones has remarkably increased in the recent years. This has revealed the lack of networks that are well prepared to respond to this kind of traffic. A hybrid distribution network can be an efficient solution for real-time streaming services. This paper contains the experimental results of streaming distribution in a hybrid architecture that consist of mixed connections among P2P and Cloud nodes that can interoperate together. We have chosen to represent the P2P nodes as Planet Lab machines over the world and the cloud nodes using a Cloud provider's network. First we present an experimental validation of the Cloud infrastructure's ability to distribute streaming sessions with respect to some key streaming QoS parameters: jitter, throughput and packet losses. Next we show the results obtained from different test scenarios, when a hybrid distribution network is used. The scenarios measure the improvement of the multimedia QoS parameters, when nodes in the streaming distribution network (located in different continents) are gradually moved into the Cloud provider infrastructure. The overall conclusion is that the QoS of a streaming service can be efficiently improved, unlike in traditional P2P systems and CDN, by deploying a hybrid streaming architecture. This enhancement can be obtained by strategic placing of certain distribution network nodes into the Cloud provider infrastructure, taking advantage of the reduced packet loss and low latency that exists among its datacenters

Peer-to-peer collaboration in content delivery networks

A low-cost collaboration architecture for web content distribution, that aims to improve all stakeholder's interests, is presented. A peer-to-peer (P2P) contribution among the end users layer is suggested, in order to increase download rates and reduce server traffic and resource usage. In addition, the Internet Service Providers (ISPs) concerns are also considered, with an ISP-aware connection strategy in the P2P protocol. Collaboration among publisher's web server resources is also proposed, in order to improve the CDN architecture performance. All the elements of this architecture have been developed and have been successfully tested in 5 different scenarios, within the PlanetLab large-scale overlay network testbed. Results show that download speed increases after implementing P2P collaboration on a content delivery scenario, with a strong reduction of data transferred via HTTP servers. The ISP-aware approach reduces inter-ISP traffic, with an increase of download speeds. This implementation is fairer as the content popularity grows because end-users extreme download rates tend to approach to the average.info:eu-repo/semantics/acceptedVersio

Cloud-based Content Distribution on a Budget

To leverage the elastic nature of cloud computing, a solution provider must be able to accurately gauge demand for its offering. For applications that involve swarm-to-cloud interactions, gauging such demand is not straightforward. In this paper, we propose a general framework, analyze a mathematical model, and present a prototype implementation of a canonical swarm-to-cloud application, namely peer-assisted content delivery. Our system – called Cyclops – dynamically adjusts the off-cloud bandwidth consumed by content servers (which represents the bulk of the provider's cost) to feed a set of swarming clients, based on a feedback signal that gauges the real-time health of the swarm. Our extensive evaluation of Cyclops in a variety of settings – including controlled PlanetLab and live Internet experiments involving thousands of users – show significant reduction in content distribution costs (by as much as two orders of magnitude) when compared to non-feedback-based swarming solutions, with minor impact on content delivery times

Implementation of a public key infrastructure over peer-to-peer network

En este proyecto se ha desarrollado la aplicación PKI-P2P, esta aplicación implementa una infraestructura de clave pública (PKI) sobre una red peer-to-peer (P2P). Una PKI tiene como objetivo probar que una clave pública es auténtica para un cierto usuario, porque la confianza que se tiene en una clave pública es muy importante para la seguridad en los métodos criptográficos. Lo normal es que el sistema sea centralizado y jerárquico en donde unos pocos elementos llamados Autoridades de Certificación (AC) son los encargados de validar la relación entre un usuario y su clave pública. En redes con una gran cantidad de nodos la PKI tiene que atender muchas peticiones de autenticidad de clave pública, por lo tanto, en este tipo de escenarios es mejor descentralizar la PKI. Para ello todos los elementos de la PKI deberían ser capaces de decidir si una clave pública es auténtica o no. Las redes descentralizadas en donde todos los elementos son iguales son las llamadas P2P, estas redes ofrecen algunas ventajas sobre los sistemas jerárquicos o centralizados como: resistencia a fallos, distribución de carga, auto administración y independencia de organización operativa. La forma de implementar una PKI sobre una red P2P es descrita en el documento de Thomas Wölfl “Public-Key-Infrastructure Based on a Peer-to-Peer Network”, el autor de este documento desarrolló una aplicación Peer-to-Peer-PKI consiguiendo búsqueda y transferencia eficiente de certificados y recomendaciones. Se basa en una combinación del modelo de Maurers y el protocolo escalable de búsqueda P2P de Chord. La red P2P utilizada es Pastry mediante su implementación en Java Freepastry, esto ha hecho que todo el proyecto se desarrolle en Java. Pastry es un esquema genérico, escalable y eficiente para aplicaciones P2P. Los nodos Pastry forman una red overlay descentralizada, auto-organizada y tolerante a fallos. Además para probar el funcionamiento de la aplicación PKI-P2P se ha utilizado la red de pruebas PlanetLab. PlanetLab es una red global de investigación para dar soporte al desarrollo de nuevos servicios de red. Gran parte del tiempo se ha dedicado al estudio de PlanetLab, saber como funciona para poder realizar las pruebas

AngelCast: cloud-based peer-assisted live streaming using optimized multi-tree construction

Increasingly, commercial content providers (CPs) offer streaming solutions using peer-to-peer (P2P) architectures, which promises significant scalabil- ity by leveraging clients’ upstream capacity. A major limitation of P2P live streaming is that playout rates are constrained by clients’ upstream capac- ities – typically much lower than downstream capacities – which limit the quality of the delivered stream. To leverage P2P architectures without sacri- ficing quality, CPs must commit additional resources to complement clients’ resources. In this work, we propose a cloud-based service AngelCast that enables CPs to complement P2P streaming. By subscribing to AngelCast, a CP is able to deploy extra resources (angel), on-demand from the cloud, to maintain a desirable stream quality. Angels do not download the whole stream, nor are they in possession of it. Rather, angels only relay the minimal fraction of the stream necessary to achieve the desired quality. We provide a lower bound on the minimum angel capacity needed to maintain a desired client bit-rate, and develop a fluid model construction to achieve it. Realizing the limitations of the fluid model construction, we design a practical multi- tree construction that captures the spirit of the optimal construction, and avoids its limitations. We present a prototype implementation of AngelCast, along with experimental results confirming the feasibility of our service.Supported in part by NSF awards #0720604, #0735974, #0820138, #0952145, #1012798 #1012798 #1430145 #1414119. (0720604 - NSF; 0735974 - NSF; 0820138 - NSF; 0952145 - NSF; 1012798 - NSF; 1430145 - NSF; 1414119 - NSF

Crowdsourced Live Streaming over the Cloud

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

Enhancing Internet-scale Video Service Deployment Using Microblog-based Prediction

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Semi-fluid: A Content Distribution Model For Faster Dissemination Of Data

Tesis ini mencadangkan serta melaksanakan suatu model agihan kandungan bagi mengurangkan atau meminimumkan kelengahan penyaluran data sebaya. Buat masa ini, agihan kandungan dalam rangkaian tindihan-atas adalah berdasarkan dua model berikut: model Kelulan dan model Bendalir. This thesis proposes and implements a novel content distribution model for reducing or minimizing delay in data dissemination