首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 625 毫秒
1.
A robust real-time video communication service over the Internet in a distributed manner is an important challenge, as it influences not only the current Internet structure but also the future Internet evolution. In this context, Peer-to-Peer (P2P) networks are playing an imperative position for providing efficient video transmission over the Internet. Recently, several P2P video transmission systems have been proposed for live video streaming services or video-on-demand services over the Internet. In this paper, we describe and discuss existing video streaming systems over P2P. Efficient (delay tolerant and intolerant) data sharing mechanisms in P2P and current video coding trends are elaborated in detail. Moreover, video streaming solutions (live and on-demand) over P2P from the perspective of tree-based and mesh-based systems are explained. Finally, the conclusion is drawn with key challenges and open issues related to video streaming over P2P.  相似文献   

2.
With the rapid development of Peer-to-Peer (P2P) technology, IPTV applications based on that have received more and more attention from both industry and academia. Several applications using the data-driven mesh-pull architectures raised and gained great success commercially. At present, PPLive system is one of the most popular instances of IPTV applications which attract a large number of users from across the globe. At the same time, however, the dramatic rise in popularity makes it more likely to become a vulnerable target. In this paper, we propose an effective measurement architecture, which is based on the peer’s nature not only receiving polluted video chunks but also forwarding those to other peers, to measure the video streaming pollution attack and then use a dedicated crawler of PPLive developed by us to evaluate the impact of pollution in P2P live streaming. Specifically, the results show that a single polluter is capable of compromising all the system and its destructiveness is severe.  相似文献   

3.
Peer-to-peer (P2P) networks have been adopted for Internet live video-streaming service, and several practical systems have been deployed in past years due to the inherent scalability and ease of deployment. However, most of these systems are commercial and proprietary, and hence little research was done in the area of characterizing practical system performance properties. In this article, we mainly present our experience on a practical P2P-based live video- streaming system called GridMedia, which was employed to broadcast live the Chinese Spring Festival Gala show over the Internet. Benefiting from two sets of flush-crowd traces with about 15,239 and 224,453 concurrent users in a 300 kb/s streaming session in 2005 and 2006, we perform a trace study to understand the service capacity, quality of streaming service, connection heterogeneity, user geographic distribution, and request and online duration characteristics. Our observations shed light on those systems and further improvements in the arena of large-scale live video-streaming service over the Internet.  相似文献   

4.
Oche  Michael  Md Noor  Rafidah  Jalooli  Ali 《Wireless Networks》2015,21(1):315-328

In order to deliver a qualitative Internet Protocol Television (IPTV) service over vehicular ad hoc networks (VANETs), a quality of service (QoS) mechanism is needed to manage the allocate of network resources to the diverse IPTV application traffic demands. Unlike other mobile network, VANETs have certain unique characteristic that presents several difficulties in providing an effective QoS. Similarly, IPTV requires a constant stream for QoS which at the moment is quite difficult due to the inherent VANET characteristics. To provide an effective QoS that will meet the IPTV application service demands, VANETs, must satisfy the compelling real-time traffic streaming QoS requirement (i.e., minimum bandwidth allocation, packet loss and jitter). In this report, we evaluate via simulation the feasibility of deploying quality IPTV services over VANETs, by characterizing the association between the IPTV streaming quality determining factors (i.e., throughput, delay, loss, jitter) and the IPTV quality degradation, with respect to node density and node velocity. Furthermore, we used an objective QoS metric (Media-Delivery-Index) to identify, locate and address the loss or out-of-order packet. We outline how, using these information’s can support in shaping network parameters to optimize service flows. The implementation assures a priority for handling IPTV traffic, such that maximise the usage of VANETs resources, and opens the possibility that loss and delay can be minimised to a degree that could guarantee quality IPTV service delivery among vehicle in a vehicular network system.

  相似文献   

5.
胡超  陈鸣  许博  李兵 《电子与信息学报》2011,33(9):2219-2224
基于P2P的IPTV(P2P-TV)是当前发展最为迅速的因特网应用之一,实时识别P2P-TV视频流是管理网络P2P-TV流量和理解网络行为的关键一步。通过分析以PPLive为代表的P2P-TV体系结构、通信过程、报文结构以及系统特征,该文提出了一种实时的基于爬虫的识别视频流CIVF算法和一种实时的基于协议特征的识别视频流PIVF算法,CIVF算法通过爬虫程序获取P2P-TV节点信息来识别P2P-TV视频流,而PIVF算法则基于视频流的通信时序和应用层负载特征实现实时识别。在因特网环境的试验分析结果表明,CIVF算法具有实现便捷但识别率不够高且节点信息残存时间较长的特点,PIVF算法则具有准确率较高、识别速度较快和扩展性强的特点。  相似文献   

6.
P2P网络流媒体关键技术   总被引:9,自引:0,他引:9       下载免费PDF全文
秦丰林  刘琚 《电子学报》2011,39(4):919-927
P2P网络流媒体技术一直是学术界和产业界的研究热点.本文围绕覆盖网络拓扑结构,对现有的P2P流媒体系统作了全面的归类总结,深入介绍和分析了覆盖网络构建、数据块调度策略等P2P流媒体核心技术,并概要讨论视频编码、网络编码、覆盖网络拓扑优化、安全与激励机制等P2P流媒体相关增强技术.对典型P2P流媒体系统的性能进行了比较,...  相似文献   

7.
Since the year of 2006,peer-to-peer (P2P) streaming media service has been developing rapidly,the user scale and income scale achieve synchronous growth.However,while people enjoying the benefits of th...  相似文献   

8.
P2P流媒体网络电视通信机制研究   总被引:1,自引:0,他引:1  
近年来兴起的P2P流媒体网络电视成为了Internet上的一种主要应用,分析和研究P2P流媒体系统对于识别其流量和日后开发类似的系统具有很强的指导意义.本文选取PPStream和QQLive两款常用软件通过抓取其流量数据进行协议分析,主要关注系统获取节点列表、资源交换和数据传输等实现方法,进而总结出了一套P2P流媒体协议分析框架,提出了一种基于协议分析的流量识别方法.  相似文献   

9.
A peer-to-peer (P2P) multimedia conferencing service is operating that users share their resources to each other on the Internet. It can solve the problem in the centralized conferencing architecture, such as the centralized loading, single point error, and expensive infrastructure. However, P2P networks have the problem that a peer has a difference between the physical location and logical location in the overlay network. In the viewpoint of P2P networks, the nearest conference resource may be far away geographically. The P2P-session initiation protocol (P2P-SIP) multimedia conference is to construct an application-based logical multicast network efficiently according to physical network information. Thus, this paper proposes a real-time streaming relay mechanism for P2P conferences on hierarchical overlay networks. The real-time streaming relay mechanism can improve the transportation efficiency of conferencing stream exchange well based on the application-layer multicast (ALM) structure and the hierarchical overlay networks.  相似文献   

10.
P2P技术在IPTV中的应用   总被引:4,自引:0,他引:4  
何晓华 《中国有线电视》2006,(12):1142-1144
IPTV是基于宽带高速IP网的流媒体服务,提出基于对等网络模式的IPTV系统,从而克服了现在IPTV系统的“瓶颈”问题,对P2P技术存在的问题进行分析并提出对策。  相似文献   

11.
A peer-to-peer(P2P) network is a distributed application architecture which provides many attractive features,such as availability,self-organization,load-balancing,and anonymity.However,P2P network has created significant problems to network operators by generating large volumes of inter autonomous system(inter-AS) traffic.Focusing on the BitTorrent swarming protocol,this paper proposes an approach which aims to reduce P2P generated inter-AS traffic.In particular,the approach can reduce inter-AS traffic by 50% to 70%.Moreover,it can improve the downloading speed by 60% for the popular torrents.The evaluation shows that controlled regional-based contents replication can effectively achieve this goal.Furthermore,the approach is incrementally deployable.Network regions in which the system gets deployed can solve their P2P generated inter-AS traffic problems autonomously,i.e.,without any Internet service providers-collaboration and any requirement,the system can be deployed in the entire Internet.  相似文献   

12.
This paper studies the conditions under which P2P sharing can increase the capacity of IPTV services over FTTN networks. For a typical FTTN network, our study shows a) P2P sharing is not beneficial when the total traffic in a local video office is low; b) P2P sharing increases the load on FTTN switches and routers in local video offices; c) P2P sharing is the most beneficial when the network bottleneck is experienced in the southbound segment of a local video office (equivalently a northbound segment of an FTTN switch); and d) sharing among all FTTN serving communities is not needed when network congestion problems are solved by using some other technologies such as program pre-caching or replication. Based on the analytical results, design for IPTV services which monitors FTTN network conditions and decides when and how to share videos among peers to maximize the service capacity. Simulations and bounds both validate the potential benefits of the MediaGrid IPTV service platform  相似文献   

13.
Wireless mesh networks (WMNs) have emerged as a promising technology that provides low‐cost broadband access to the Internet for fixed and mobile wireless end users. An orthogonal evolution in computer networking has been the rise of peer‐to‐peer (P2P) applications such as P2P data sharing. It is of interest to enable effective P2P data sharing in this type of networks. Conventional P2P data sharing systems are not cognizant of the underlying network topology and therefore suffer from inefficiency. We argue for dual‐layer mesh network architecture with support from wireless mesh routers for P2P applications. The main contribution of this paper is P2PMesh: a topology‐aware system that provides combined architecture and efficient schemes for enabling efficient P2P data sharing in WMNs. The P2PMesh architecture utilizes three schemes: (i) an efficient content lookup that mitigates traffic load imbalance at mesh routers; (ii) an efficient establishment of download paths; and (iii) a data transfer protocol for multi‐hop wireless networks with limited capacity. We note here that the path establishment and data transfer schemes are specific to P2P traffic and that other traffic would use routes determined by the default routing protocol in the WMN. Simulation results suggest that P2PMesh has the potential to improve the performance of P2P applications in a wireless multi‐hop setting; specifically, we focused on data sharing, but other P2P applications can also be supported by this approach. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

14.
The concept of the ??future Internet?? has evolved amongst researchers recently to relieve the tremendous pressure on the current Internet infrastructure to support the heterogeneous networking technologies, mobile devices, increased population of users, and also the high user requirements for real-time services and applications. Peer-to-Peer (P2P) Video on Demand (VoD) streaming technologies are expected to be a key technology in the future Internet. Because the existing P2P streaming techniques are attributed to a number of shortcomings, P2P VoD schemes need to be adequately redesigned for the future Internet. In this paper, we propose a scheme to effectively provide VoD by using P2P-based mesh overlay networks that may be suitable for the future Internet. Our scheme selects the most appropriate peers by exploiting domain-based localization and congestion awareness strategies. Through simulations, our proposed scheme is demonstrated to have scalability and capability of reducing the startup delay and total link cost, while maintaining high playback rate. The results are encouraging and show the importance of redesigning P2P VoD services in future Internet.  相似文献   

15.
Inferring Network-Wide Quality in P2P Live Streaming Systems   总被引:2,自引:0,他引:2  
This paper explores how to remotely monitor network-wide quality in mesh-pull P2P live streaming systems. Peers in such systems advertise to each other buffer maps which summarize the chunks of the video stream that they currently have cached and make available for sharing. We demonstrate how buffer maps can be exploited to monitor network-wide quality. We show that the information provided in a peer's advertised buffer map correlates with that peer's viewing-continuity and startup latency. Given this correlation, we remotely harvest buffer maps from many peers and then process these buffer maps to estimate the video playback quality. We apply this methodology to a popular P2P live streaming system, namely, PPLive. To harvest buffer maps, we build a buffer-map crawler and also deploy passive sniffing nodes. We process the harvested buffer maps and present results for network-wide playback continuity, startup latency, playback lags among peers, and chunk propagation patterns. The results show that this methodology can provide reasonably accurate estimates of ongoing video playback quality throughout the network.  相似文献   

16.
随着以数字经济为代表的新兴互联网产业快速崛起,消费互联网向产业互联网转型升级,众多企业信息系统分散部署于多个云平台以及传统IDC中,它们需要一个“平等的”、“互利的”场所进行企业信息上云和云间互联业务流量疏导,需要实现高效、快速、灵活的与各类型云服务商互联。然而互联网发展初期就已经形成的层级化网络架构决定了下层中小网络为了实现跨网流量转发需要向上层网络缴纳高昂的流量转接费用,并且内容源和用户之间分属不同网络,流量绕行时延较大,影响网络质量。互联网交换中心应运而生,并且已经成为国际上重要的网络信息基础设施和流量交互节点,本文旨在研究国内互联网交换中心建设环境,提出新型互联网交换中心组网架构方案建议。  相似文献   

17.
Traffic theory and the Internet   总被引:8,自引:0,他引:8  
We argue that traffic theory, an essential component in the design of traditional telecommunications networks, should be increasingly applied in the development of the multiservice Internet. We discuss the statistical characteristics of Internet traffic at different time scales. Modeling is facilitated on identifying the notion of flow and distinguishing the categories of streaming and elastic traffic. We review mathematical modeling approaches useful for predicting the relationship between demand, capacity and performance for both streaming and elastic flows. Derived results indicate the limitations of service differentiation as a means for guaranteeing QoS and highlight the importance of traditional traffic engineering approaches in ensuring that the network has sufficient capacity to handle offered demand  相似文献   

18.
Introduction TV services over the Internet can be provided by either exploiting IP multicast functionalities or relying on a pure peer-to-peer (P2P) approach. The first technique will only work on a network infrastructure controlled by a single broadband operator due to limitations of IP multicast facilities. The main goal of the project is the study of a future system suitable for HQTV live streaming over the Internet based on P2P technology, or a P2P-HQTV system. The major focus is on overcoming today's pure layered approach through a cooperative paradigm in which the application and network layers cooperate to optimize the quality of service offered to end users.  相似文献   

19.
随着互联网的迅猛发展,P2P技术在互联网上的应用超过了Web而成为在流量上占据统治地位的新型应用。同时,P2P技术的影响力不仅限于互联网,还间接地延伸到了电信网和广电网。使用P2P技术的新业务对传统领域带来冲击的同时,也协助解决了三网融合的技术瓶颈。ENUM技术作为跨越互联网和电信网的基础性架构,是融合网络的一条重要的技术途径。将ENUM技术与P2P相结合,可以使P2P共享的优势延伸到电信网络,加速网络融合。  相似文献   

20.
Routing has always been a great challenge for structured Peer-to-Peer (P2P) networks. There are a lot of representative structured routing algorithms for P2P networks, but these algorithms do not guarantee the quality of service (QoS) for real-time P2P applications. Addressing this challenge, a traffic prediction-based structured routing algorithm over P2P networks (TPSR) is proposed. Our contributions are described as below. We firstly analyze P2P traffic features and then build a wavelet neural-network predicting model. Secondly, we employ the traffic prediction model to predict the future state of each peer, such as normal or congestion, and let each peer update its routing table. In this way the requesting peers always get a resource list which contains the best resource peers. Simulation results demonstrate that TPSR has higher transmission success rate and lower end to end delay than other structured routing algorithms. Thus, TPSR can guarantee the QoS for real-time P2P applications.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号