IPTV业务发展趋势分析

IPTV又称为互动电视、宽带电视或网络电视，是指以电视机和机顶盒为客户终端。通过宽带网络为用户提供的交互式多媒体服务，包括通信、视频内容、互联网应用等。1999年英国Video Networks公司率先在全球推出IPTV业务，近年来境外宽带接人商纷纷推出IPTV业务。我国的IPTV市场也正在起步。     

IPTV要傍着宽带兴

2005年元旦期间,山东威海信息港宽带应用平台用户张先生对IPTV有了切身感受,视频点播的大片让他直呼过瘾。IPTV是利用IP宽带网络,集互联网、多媒体、通信等多种技术于一体,向用户提供直播电视、视频点播、上网浏览等多种交互式服务的业务。用户可以通过“IP机顶盒 电视”或电脑两种方式使用IPTV业务。     

IPTV业务分析

1.前言IPTV即交互式网络电视,是一种利用宽带IP网络,集互联网、多媒体、通讯等多种技术于一体,以电视机或PC机作为接收终端,向用户提供包括数字电视在内的多种交互式服务的崭新技术。IPTV利用ADSL或以太网或者有线电视网络等接入宽带网,通过互联网协议(IP协议)来传送电视信号,是互联网和传统电视相     

基于WiMAX技术的远程移动视频监视系统探究

随着我国信息技术与网络技术的飞速发展,国家的监视网络得到了很大的发展空间。基于WiMAX技术的城域网,运用了先进的天线技术和数据传输技术,将移动宽带的无线接入问题合理解决,将多种宽带多媒体业务结合在一起完成了数据、信息、语音、图像、视频的高效传播。随着WiMAX技术的不断发展和完善,WiMAX逐渐实现移动化,可以为用户提供高速移动下的高效数据传输业务。目前,该技术广泛应用于移动视频监控工作中,本文主要对基于WiMAX技术的远程移动视频监视系统进行研究。     

3TNet网络电视多画面监控系统设计与实现

针对网络电视监控这一新业务,通过分析系统实现的诸多难点,结合高性能宽带信息网(3Tnet)网络架构和网络电视(IPTV)服务模型,提出IPTV多画面监控系统的设计方案,以解决IPTV环境下电视播出质量监控困难的难题,为IPTV运营商提供了便利。该系统已用于3TNet网络电视实际运营中,效果良好。     

城域网网络架构优化研究

随着互联网经济的全面发展,宽带城域网也开始承担语音、电视视频等多种非传统业务,全业务网络IP化、IP网络云化的趋势越来越明显.建设一个对于用户和运营商都相对而言较为低成本、易扩展、灵活高效的城域网网络也就显得至关重要.本文通过对城域网现网架构及业务发展需求的具体分析,探讨网络的演进的具体思路.     

网络电视延时续播的设计与实现

随着互联网的迅速发展,网络电视通过互联网协议(IP)来提供包括电视节目在内的多种数字多媒体服务及其增值业务。大多数网络电视支持直播电视以及基于IP网络的视频点播服务,改变了传统电视单向广播的特点。本文介绍一种在当前网络电视系统中实现延时续播(对直播电视提供暂停、快退操作)功能的方案。     

IPTV业务发展分析

IFTV是一种利用宽带网络为用户提供交互式多媒体服务的业务，其主要特点在于交互性和实时性。通过IFTV业务．用户可以得到高质量的数字媒体服务，可以自由地选择宽带IP网的视频节目．实现媒体提供和媒体消费的实质性互动。     

流媒体海量存储节目源

网络电视、网上视频点播已经越来越广泛地应用于各行各业,湖北电信的视频服务平台的搭建为实现这些应用奠定了基础。创智公司的银鲨流媒体视频服务平台成为全省公司的一个宽带流媒体运营支撑平台。目前,该平台的建设目标是在多媒体宽带平台上实现两种业务:VOD 视频点播和网络电视。这项工程将在湖北电信现有平台的基     

基于模糊逻辑技术的切换策略

下一代宽带无线通信网在为用户提供高速率语音服务以及图像、视频信息的传输和高速接入Internet服务等丰富的业务类型的同时,也给系统的切换策略带来新的挑战。以往仅考虑单一因素对系统影响的切换策略已不适用于具有丰富业务类型的下一代宽带无线通信网络。该文利用模糊逻辑技术进行切换过程中的目标小区选取。相比传统方案,模糊逻辑技术可以兼顾多种因素,使得选取结果更加合理,并且可以均衡系统负载、减少切换的拒绝率。     

DVB-IPTV content download services—overview and use cases

IPTV services have been widely deployed by network operators around the world over the last years. However, real-time streaming of Linear TV and Video-on-Demand (VoD) offerings, especially in High Definition quality, still puts a high burden on the network and content servers concerning bandwidth, Quality-of-Service, processing performance and scalability if 100.000s of users have to be supported simultaneously. While multicast delivery can cope with some of these problems for Linear TV services, the unicast VoD services cannot take advantage of that and especially the request for on-demand content is expected to substantially grow in the future. With the introduction of Content Download Services (CDSs), operators have the option to provide IPTV services in innovative ways: They can provide high-quality video services to users with limited access bandwidth, offload the streaming request for blockbuster movies at peak times from the VoD servers or provided personalized advertisements for insertion into a live program event in advance to the users end device. The Digital Video Broadcast (DVB) Project has recently finalized its CDS specification within its IPTV specification efforts. DVB CDS supports push and pull delivery models with unicast, multicast and peer-to-peer distribution in order to enable various business models and use cases. In this work we introduce the specified technology and map it to example use cases and business models.     

基于P2P技术的IPTV解决方案研究与设计

传统地在Internet上提供电视广播服务是采用Client/Server架构,但随着使用人数的增加Server负载日益增大,服务供应者必须负担的成本会越来越高。而IPTV是集宽带有线电视网、因特网、多媒体通讯等多种技术于一体提供包括数字电视在内的多种交互式服务的一种崭新技术。随着Internet使用人数的增加,Client/Server架构所面临的问题日益严重,使得P2P(Peer to Peer)技术逐渐被重视。文章介绍了P2P技术的原理,将Client/ServerIPTV与P2P IPTV进行了性能上的比较,最后提出一种P2P IPTV的解决方案。     

基于校园网络的PeerCast数字直播系统

随着Internet的普及及信息技术的发展,传统客户机/服务器模式的IPTV,由于服务器I/O瓶颈的限制,已无法满足越来越多用户同时收视的需要。而在文件共享系统和数据库应用中使用PeerCast技术能够充分利用闲置的网络资源,实现有效的负载均衡,更适合应用在大规模的数字直播系统中。     

基于爬行器的大规模P2P IPTV测量

为了解大规模P2P IPTV系统中的用户行为特征和拓扑结构特征等内在信息,开发和部署了一个多协议P2P IPTV爬行器TVCrawer,对3个主流的P2P IPTV系统--PPLive,PPStream和UUSee进行了大量的主动测量,并对P2P IPTV系统中的用户行为和网络拓扑特征进行了分析和比较.主要发现包括:1...     

Modeling and evaluating IPTV applications in WiMAX networks

Internet Protocol-based Television (IPTV) is a digital television service which delivers television content via an IP network. The rapid growth of wireless network technology in recent years has changed, the way people access the Internet. Adding mobility to IPTV can create a truly compelling ubiquitous service which spans different network domains and varied IP-enabled terminals and devices, such as set-top boxes, PCs and cell phones. However, extending IPTV service to wireless networks requires overcoming bandwidth bottlenecks and high packet loss rates. Following the IEEE 802.16 standard, worldwide interoperability for microwave access (WiMAX) features high data rates and large service coverage, offering a wireless broadband solution for IPTV services. While previous research has focused on creating a broadband IPTV service few studies have practically evaluated IPTV applications in a wireless broadband network environment. In this paper, we model and evaluate a common constant bit rate (CBR)¹ based IPTV application and an IPTV live streaming (PPStreaming)² application while retrieving IPTV content via a WiMAX network. We also use the NS2 simulation tool to evaluate the performance of these two IPTV applications. The evaluation metrics include latency, packet loss, data rate and throughput statistics when the two IPTV applications are run in the WiMAX network. ¹The simplest IPTV solution is to convey video content by CBR. IPTV operators and content delivery networks relay CBR streaming content to control the demand for network capacity. Broadcasters prefer CBR video as it conserves bandwidth resources, but CBR delivery can degrade video quality result in higher overall demand on network capacity. ²PPStreaming (also referred to as P2P streaming Internet TV) is a network for live media streaming. In principle it’s similar to BitTorrent (BT) in that it provides stable and smooth broadcast of TV programs to broadband users. Unlike traditional streaming media, PPStreaming adopts P2P-streaming technology and supports full-scale visits with tens of thousands of simultaneous users. Its client software can be used in the browser or as a standalone executable.     

A Measurement Study of a Large-Scale P2P IPTV System

An emerging Internet application, IPTV, has the potential to flood Internet access and backbone ISPs with massive amounts of new traffic. Although many architectures are possible for IPTV video distribution, several mesh-pull P2P architectures have been successfully deployed on the Internet. In order to gain insights into mesh-pull P2P IPTV systems and the traffic loads they place on ISPs, we have undertaken an in-depth measurement study of one of the most popular IPTV systems, namely, PPLive. We have developed a dedicated PPLive crawler, which enables us to study the global characteristics of the mesh-pull PPLive system. We have also collected extensive packet traces for various different measurement scenarios, including both campus access networks and residential access networks. The measurement results obtained through these platforms bring important insights into P2P IPTV systems. Specifically, our results show the following. 1) P2P IPTV users have the similar viewing behaviors as regular TV users. 2) During its session, a peer exchanges video data dynamically with a large number of peers. 3) A small set of super peers act as video proxy and contribute significantly to video data uploading. 4) Users in the measured P2P IPTV system still suffer from long start-up delays and playback lags, ranging from several seconds to a couple of minutes. Insights obtained in this study will be valuable for the development and deployment of future P2P IPTV systems.     

On performance of group key distribution techniques when applied to IPTV services

IPTV services consist of multiple video channels grouped in bundles, such as sports, movies or generic bundles; users typically subscribe multiple bundles, including the generic bundle. Secure IP multicast can be used to implement IPTV services, but it still has problems to be addressed. Current solutions require high computational power in video channel zapping situations, lack support for groups sourced at the users, and present a weak support for admission control in IP multicast for both sources and receivers in dynamically configured environments.This work proposes a new, secure and efficient IPTV solution that, cumulatively: (a) enforces individual access control to groups of real-time IPTV video channels; (b) enforces IP multicast admission control for both multicast senders and receivers; (c) supports user generated videos; (d) generates low signaling overheads; (e) does not introduce perceivable delays, particularly in video channel zapping situations. Moreover, this solution can be easily integrated in the IPTV architectures being developed by ETSI and ITU-T.     

一种两阶段自适应的IMS-Based IPTV应用服务器负载均衡策略

随着IPTV用户数目的增长,IPTV应用服务器的负担愈加繁重。在这种情况下,集群系统逐渐成为构建高性能和高服务质量的一种有效的应用服务器体系结构。保证应用服务器各节点的负载均衡,可以有效提高系统的吞吐量,提高IPTV服务质量。针对负载均衡问题,提出了一种基于IPTV用户行为特点的,两阶段自适应负载均衡策略,负载均衡器通过实时监控应用服务器集群内各节点的负载情况,动态修改各节点负载分配权值。算法在保持应用服务器各节点负载均衡的同时,维护用户会话的完整性,保证了服务质量QoS（Quality of Services）。仿真结果显示此算法具有较好的性能,能在保证服务质量的前提下有效地提高系统吞吐量。     

PTV质差用户故障处理监控系统

Aiming at the problem that the existing IPTV quality monitoring platform cannot match poor quality accounts with user in- formation, and cannot accurately push the details of users with poor quality of broadcast to front-line maintenance personnel, this pa- per implements the IPTV monitor system for poor quality treatment. It uses image recognition algorithms to identify poor-quality ac- counts in batches, automatically extract related information between multiple systems, and directly push the poor-quality informa- tion to front-line personnel according to the maintenance area. The application shows that the system effectively improves the rate of IPTV poor quality in cities and towns, saves labor costs for data extraction, and realizes multi-dimensional monitoring and analysis of IPTV poor quality data.     

基于可伸缩编码的高清IPTV系统

随着移动互联网技术与智能手持设备的发展,IPTV面临多屏融合的需求,可伸缩编码技术可以很好地解决网速和设备分辨率的差异问题．本文设计和实现了一套基于H264／SVC标准的高清实时IPTV系统,通过对视频在时间、空间、质量上进行可伸缩编码,以及TS解封装、AVC解码和TS流传输H264／SVC等模块的实现,通过实时编码,使拥有不同带宽和设备分辨率的用户能并发实时地观看节目．实验证明了系统的有效性和稳定性．