CloudMedia: When cloud on demand meets video on demand

Internet-based cloud computing is a new computing paradigm aiming to provide agile and scalable resource access in a utility-like fashion. Other than being an ideal platform for computation-intensive tasks, clouds are believed to be also suitable to support large-scale applications with periods of flash crowds by providing elastic amounts of bandwidth and other resources on the fly. The fundamental question is how to configure the cloud utility to meet the highly dynamic demands of such applications at a modest cost. In this paper, we address this practical issue with solid theoretical analysis and efficient algorithm design using Video on Demand (VoD) as the example application. Having intensive bandwidth and storage demands in real time, VoD applications are purportedly ideal candidates to be supported on a cloud platform, where the on-demand resource supply of the cloud meets the dynamic demands of the VoD applications. We introduce a queueing network based model to characterize the viewing behaviors of users in a multichannel VoD application, and derive the server capacities needed to support smooth playback in the channels for two popular streaming models: client-server and P2P. We then propose a dynamic cloud resource provisioning algorithm which, using the derived capacities and instantaneous network statistics as inputs, can effectively support VoD streaming with low cloud utilization cost. Our analysis and algorithm design are verified and extensively evaluated using large-scale experiments under dynamic realistic settings on a home-built cloud platform. © 2011 IEEE.published_or_final_versionThe 31st International Conference on Distributed Computing Systems (ICDCS 2011), Minneapolis, MN., 20-24 June 2011. In Proceedings of 31st ICDCS, 2011, p. 268-27

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

Bandwidth-efficient Video Streaming with Network Coding on Peer-to-Peer Networks

PhDOver the last decade, live video streaming applications have gained great popularity among users but put great pressure on video servers and the Internet. In order to satisfy the growing demands for live video streaming, Peer-to-Peer(P2P) has been developed to relieve the video servers of bandwidth bottlenecks and computational load. Furthermore, Network Coding (NC) has been proposed and proved as a significant breakthrough in information theory and coding theory. According to previous research, NC not only brings substantial improvements regarding throughput and delay in data transmission, but also provides innovative solutions for multiple issues related to resource allocation, such as the coupon-collection problem, allocation and scheduling procedure. However, the complex NC-driven P2P streaming network poses substantial challenges to the packet scheduling algorithm. This thesis focuses on the packet scheduling algorithm for video multicast in NC-driven P2P streaming network. It determines how upload bandwidth resources of peer nodes are allocated in different transmission scenarios to achieve a better Quality of Service(QoS). First, an optimized rate allocation algorithm is proposed for scalable video transmission (SVT) in the NC-based lossy streaming network. This algorithm is developed to achieve the tradeoffs between average video distortion and average bandwidth redundancy in each generation. It determines how senders allocate their upload bandwidth to different classes in scalable data so that the sum of the distortion and the weighted redundancy ratio can be minimized. Second, in the NC-based non-scalable video transmission system, the bandwidth ineffi- ciency which is caused by the asynchronization communication among peers is reduced. First, a scalable compensation model and an adaptive push algorithm are proposed to reduce the unrecoverable transmission caused by network loss and insufficient bandwidth resources. Then a centralized packet scheduling algorithm is proposed to reduce the unin- formative transmission caused by the asynchronized communication among sender nodes. Subsequently, we further propose a distributed packet scheduling algorithm, which adds a critical scalability property to the packet scheduling model. Third, the bandwidth resource scheduling for SVT is further studied. A novel multiple- generation scheduling algorithm is proposed to determine the quality classes that the receiver node can subscribe to so that the overall perceived video quality can be maxi- mized. A single generation scheduling algorithm for SVT is also proposed to provide a faster and easier solution to the video quality maximization function. Thorough theoretical analysis is conducted in the development of all proposed algorithms, and their performance is evaluated via comprehensive simulations. We have demon- strated, by adjusting the conventional transmission model and involving new packet scheduling models, the overall QoS and bandwidth efficiency are dramatically improved. In non-scalable video streaming system, the maximum video quality gain can be around 5dB compared with the random push method, and the overall uninformative transmiss- sion ratio are reduced to 1% - 2%. In scalable video streaming system, the maximum video quality gain can be around 7dB, and the overall uninformative transmission ratio are reduced to 2% - 3%

Collaborative communications among multiple points.

Zhang Xinyan.Thesis (M.Phil.)--Chinese University of Hong Kong, 2004.Includes bibliographical references (leaves [78]-[85]).Abstracts in English and Chinese.Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Multiple Point Communication --- p.1Chapter 1.2 --- Major Contributions --- p.2Chapter 1.3 --- Thesis Organization --- p.4Chapter 2 --- Related Work --- p.5Chapter 2.1 --- Peer-to-Peer Networks --- p.5Chapter 2.2 --- Application Layer Multicast --- p.11Chapter 2.3 --- Internet Traffic Engineering --- p.19Chapter 3 --- MultiServ: Application Layer Multiple Path Routing --- p.23Chapter 3.1 --- Motivation --- p.24Chapter 3.2 --- MultiServ Overlay Construction --- p.28Chapter 3.3 --- MultiServ Routing --- p.33Chapter 3.3.1 --- The importance of routing strategy --- p.33Chapter 3.3.2 --- Solutions for IP network --- p.35Chapter 3.3.3 --- MultiServ routing --- p.37Chapter 3.3.4 --- MultiServ routing with bounded complexity --- p.39Chapter 3.3.5 --- Routing implementation --- p.41Chapter 3.4 --- Performance Evaluation --- p.45Chapter 3.4.1 --- End-to-end streaming --- p.45Chapter 3.4.2 --- Application-layer multicast --- p.50Chapter 3.4.3 --- Experiments in real network --- p.54Chapter 3.5 --- Summary and Future Work --- p.57Chapter 4 --- DDS: Distributed Dynamic Streaming --- p.59Chapter 4.1 --- Motivation --- p.59Chapter 4.2 --- Distributed Dynamic Streaming --- p.61Chapter 4.2.1 --- DDS overlay construction --- p.62Chapter 4.2.2 --- DDS streaming --- p.64Chapter 4.3 --- Performance Analysis in Dynamic User Environment --- p.66Chapter 4.3.1 --- Basic definition and user model --- p.67Chapter 4.3.2 --- Data outage in tree topology --- p.68Chapter 4.3.3 --- Data outage in DDS --- p.70Chapter 4.4 --- Performance Evaluation --- p.73Chapter 4.4.1 --- Simulation setup --- p.73Chapter 4.4.2 --- Simulation results --- p.74Chapter 4.5 --- Summary and Future Work --- p.75Chapter 5 --- Concluding Remarks --- p.76Bibliography --- p.7

Distributed rate allocation for multi-flow video delivery

We consider rate-distortion (RD) optimized multi-flow video delivery in unstructured overlay networks. We show that this problem can be studied as a distributed rate allocation. To solve the problem over the participating peers in the overlay, we apply classical decomposition techniques such that the network-wide utility of video distortion is minimized. Media packets are assumed to be piggy-backed with RD preambles that contain information regarding their impact on decoder video distortion and their size. This allows for converting the calculated optimal rate allocation at every node into simple forwarding or dropping actions. Furthermore, the proposed distributed media streaming framework employs a network inference algorithm for minimizing the flow of duplicate packets over the network and utilizing thus more efficiently the available resources. Our simulation results indicate that significant quality benefits can be achieved when the precise RD characteristics of a media presentation are taken into account

Development of advanced multimedia services in P2P architectures

La transmissió de fluxos multimèdia en temps real (streaming) s’ha convertit en un tema punter i de gran interès al món de la recerca d’Internet, especialment quan ens referim a aplicacions de transmissió d’àudio i vídeo en directe a través de xarxes peer-to-peer (P2P). Generalment, aquestes aplicacions han de fer front a molts problemes en el seu disseny i implementació deguts a la dinamicitat i heterogeneïtat que per natura caracteritzen les xarxes P2P. En aquest projecte, s’introdueixen noves característiques que les aplicacions de transmissió multimèdia P2P actuals no contemplen. Els requisits de connexió i maquinari són diferents per a la transmissió de fluxos de baixa i alta capacitat, no obstant, tots els nodes s’acostumen a considerar idèntics, cosa que no representa una aproximació gaire encertada tenint en compte un medi tan heterogeni. A més a més, amb la finalitat d’aconseguir distinció entre nodes, es fa necessari la introducció d’un mecanisme que permeti l’intercanvi de les capacitats específiques de cada node, incloent-hi les de transcodificació de fluxos. Un altre aspecte a destacar és el fet que aquestes aplicacions són difícils d’ampliar, incorporar nous serveis o modificar les dades que porten precarregades com ara la llista de canals de televisió disponibles, cosa que impossibilita garantir la disponibilitat de la font tot el temps. Per altra banda, els serveis interactius tampoc s’han desenvolupat gaire. Aquest projecte proposa el disseny i implementació d’una plataforma de difusió multimèdia P2P cooperativa i interactiva que permet superar els problemes esmentats. La plataforma integra diferents mecanismes que permeten la distribució en temps real de continguts multimèdia en diferents qualitats incloent fluxos d’alta capacitat (com per exemple HD). Aquesta plataforma és una solució novedosa basada en JXTA, DONET i ALM (Arbres Multicast a nivell d’Aplicació) que proporciona un sistema ampliable segons noves necessitats i facilita la inserció de nous serveis de valor afegit. La plataforma proposada es fonamenta en la creació d’una arquitectura de 2 capes lògiques superposades: una capa lògica JXTA, encarregada bàsicament de la senyalització i intercanvi de metadades, i una capa de transmissió basada en sockets UDP unicast. D’aquesta manera, la diferència entre la capa de transmissió i la capa física es pot veure reduïda a partir de la informació obtinguda de la capa JXTA, la qual es va actualitzant al llarg del temps