FTTH家庭网关及其对视频业务的承载

基于EPON接入结构,提出了一种FTTH家庭网关的总体设计方案,该方案在用户端能够为用户提供视频、语音和数据三种业务的接口,实现三种业务的融合.尤其是在视频业务的承载方面,综合IPTV与DVB的优点,通过灵活组合,为用户提供H.264和MPEG-2两种编码方式的视频节目的接收平台.分析比较了两种编码方式的点播节目对带宽需求的差别.     

运营商三网融合接入控制方式探讨

1前言三网融合是电信网、计算机网和有线电视网通过技术改造,能够提供包括语音、数据、图像等综合多媒体的通信业务。各大运营商目前已经能够提供VoIP语音和高速互联网数据接入,三网融合在接入控制层面主要是考虑IPTV的接入方式以及如何在多业务接入模式下实现综合运营并保障各类业务的服务质量。     

基于大规模接入汇聚路由器的IPTV系统

介绍网络电视（IPTV）和组播技术的概念,及实现IPTV业务必须的关键技术,给出了在大规模接入汇聚路由器上实现IPTV业务的一种系统结构。     

IPTV中的接入网络新技术

在分析IPTV业务需求的基础上,结合目前开展IPTV业务面临的问题和现实情况,详细介绍了IPTV业务中接入网络的热点技术及方案。     

IPTV关键技术探证

IPTV又称为网络电视、宽带电视，是利用宽带网络为用户提供交互式多媒体服务的一种业务。IPTV视频流经过高效的压缩编码后送到IP网络上，通过位于宽带网络边缘的IP电视终端设备，为用户提供直播电视、按需视频和个人录像等服务。IPTV的主要特点在于交互性和实时性，可以实现媒体提供者和消费者之间的真正实时互动。用户可以自由选择宽带IP网络中的视频节目，并得到接近DVD水平的数字媒体服务。     

IP城域网组网演进分析

IP城域网面临着由单一业务承载向多种业务承载的转变.作为数据、语音、视频业务的综合承载网络,IP城域网应满足互联网接入、企业互连、IPTV、软交换/3G等业务的承载以及提供差异化服务的要求.以"统一的路由核心层 接入控制层多边缘 接入层多边缘方案"结构构建的IP城域网具有很强的扩展性、高带宽和价格优势,配合以"大容量、少局所、广覆盖"的布局思路,采用"网络层次化、结构扁平化、业务分离化、接入多样化"的建设方案,IP城域网必将成为各种业务的统一承载平台.成为运营商成功运营的关键基础.     

基于IMS架构的IPTV系统的研究

文章提供一种在IP多媒体子系统（IMS）网络中实现交互式网络电视（IPTV）业务的方案。方案采用超文本传输呼叫会话控制功能设备（H—CSCF）提供Mw接口，接入IMS核心网，实现IPTV和IMS业务的融合组网。使得运营商无需对现有大量的IPTV终端进行升级和改造，就能在基于IMS的电信融合网络中提供IPTV业务；同时提供统一的用户管理、服务质量（QoS）保证、并支持与下一代网络其他业务的融合。对于已经布置了基于IMS通信网络的运营商，采用该方案可以简单地提供IPTV业务，也可以支持IPTV与其他通信业务的融合；同样对于已经布置了IPTV系统的运营商，采用该方案可以通过对核心设备的简单升级和改造，实现和IMS核心网的融合，降低运营成本。     

IPTV接入网络故障处理解析

随着国内IPTV业务的快速发展,对IPTV故障的快速、高质量的处理已经成为了用户的普遍要求.而IPTV承载网接入层是整个承载网最关键的环节,负责IPTV用户的业务接入认证、面向用户组播复制、区分于宽带上网业务的QoS保证等等.如何更好更快地处理这部分故障,是影响IPTV业务质量体验的关键点.本文就是针对IPTV接入网络主要故障进行了原因判断和处理解析.     

IPTV业务中的应用层差错控制技术分析

在IP网络上提供网络电视(IPTV)业务要面对传输带宽、传输延时和抖动、丢包等困难.以终端为中心的实现方案通过在接收终端以及信源编码中加入一定的控制策略如拥塞控制策略、差错控制策略,可以较好地改善图像质量.在IP网络上采用端到端的应用层可靠性解决方案,能很好的提供IPTV业务.应用层前向纠错(AL-FEC)技术解决网络丢包问题,从而保证端到端的可靠性.     

IPTV计费系统与SP系统间接口的实现方案

IP电视(IPTV)业务正逐渐走向实际运营阶段,成为电信运营商的主流宽带业务.为了IPTV业务的长期有序发展,迫切需要建立适合IPTV业务运营的计费系统.文章描述了基于IPTV增值业务平台的计费系统的总体构成,说明了该系统中IPTV业务运营平台与服务提供商(SP)系统之间接口的定义,在此基础上详细分析了该接口与计费相关的功能需求,最后,给出了该接口的实现方案.     

IPTV--三网融合的开端

IPTV与目前的3个运营网（有线电视网、Internet和电信网）及其业务直接相关。但不同运营商对IPTV业务有不同定位。电信运营商认为IPTV业务体现于电视节目在IP网中的组织和传送形式，有线电视网络运营商认为IPTV业务是利用有线电视网来提供数字电视节目和电视节目以外的信息服务。由于IPTV业务分为广播业务和交互型业务两大类，支撑这两类业务的承载网也相应地分别采用单向广播网和双向交互网，因而在承载网层很难融合。融合工作将在业务层发生，即充分利用已经存在的两个承载网来经济、高效地发展业务。IPTV中既拥有广播型业务，又拥有组播型业务，还拥有交互型业务，将是三网融合的开端。     

取证水印在IPTV中的应用

IPTV业务的迅速发展,对于以防止盗版为目的IPTV安全方案提出了更高的要求。基于取证水印的IPTV安全方案是对普通数字版权管理方案的补充,它是在视频流通过数字电视机顶盒时将具有特殊身份标识的水印嵌入视频,从而能够追踪盗版责任人,保证IPTV内容安全。介绍了取证水印的基本原理,分析了现有的各种基于取证水印的IPTV安全方案并给出比较。     

Joint video coding of MPEG-2 video programs for digitalbroadcasting services

In digital broadcasting services such as digital satellite TV, cable TV, and digital terrestrial TV, several video programs are compressed by MPEG-2 and then simultaneously transmitted over a conventional CBR (constant bit rate) broadcasting channel. In this environment, the picture quality of the aggregated video programs should be kept as equal as possible to provide fair video services for all the viewers. We propose a joint video coding scheme for ensuring that the picture quality of all the programs are nearly the same. This objective is achieved by simultaneously controlling the video encoders to generate the VBR (variable bit rate) compressed video streams. This paper contributes in two ways. First, we propose a rate-distortion estimation method for MPEG-2 video, which enables us to predict the amount of bits and the distortion generated from an encoded picture at a given quantization step size and vice versa. The most attractive features of the proposed estimation method are its accuracy and a computational complexity low enough to be applied to real-time video coding applications. Second, this paper presents an efficient and accurate joint video coding scheme using the rate-distortion estimation results. The experimental results show that our coding scheme gives a higher and more stable picture quality and a more efficient channel utilization than an independent coding scheme that encodes each program independently     

Improving IPTV Forwarding Mechanism in IEEE 802.16j MMR Networks Based on Aggregation

Internet protocol television (IPTV) service depends on the network quality of service (QoS) and bandwidth of the broadband service provider. IEEE 802.16j mobile multihop relay Worldwide Interoperability for Microwave Access networks have the opportunity to offer high bandwidth capacity by introducing relay stations. However, to actually satisfy QoS requirements for offering IPTV services (HDTV, SDTV, Web TV, and mobile TV) for heterogeneous users' requests, providers must use a video server for each IPTV service type, which increases the network load, especially bandwidth consumption and forwarding time. In this paper, we present a solution for forwarding IPTV video streaming to diverse subscribers via an 802.16j broadband wireless access network. In particular, we propose a new multicast tree construction and aggregation mechanism based on the unique property of prime numbers. Performance evaluation results show that the proposed scheme reduces both bandwidth consumption and forwarding time.     

浅谈IPTV技术

IPTV是一种最新流行的、以“电视机+机顶盒”为主要终端设备、能为用户提供互动多媒体服务的宽带增值业务,它为我国广大电视用户提供了全新的宽带体验方式。IPTV技术是一项系统技术,包括多方面的内容,文章主要介绍了IPTV技术中的音视频编解码、流媒体传送、宽带接入网络、IP机顶盒等技术。     

现阶段IPTV面临的主要问题及其发展方向

IPTV也可以称为宽带网络电视,是基于IP协议的电视广播服务,通过互联网向用户提供视频、音频信息服务,主要论述IPTV的关键技术及其发展策略等问题。     

QoE-aware mobile IPTV channel control algorithm over WiMAX network

In this paper, we present an effective IPTV channel control algorithm that improves the quality of experience for subscribers to mobile IPTV services over WiMAX network. We consider the video quality of TV channels and the channel zapping time as quality of experience metrics. The proposed algorithm controls the channel distribution state and the target bit rate of TV channels based on the channel preference information of subscribers to achieve an effective trade-off between channel zapping time and video quality. Finally, simulation results are provided to demonstrate the performance of the proposed system.     

Resource Management and QoS Provisioning for IPTV over mmWave-based WPANs with Directional Antenna

There is an increasing interest in 60 GHz millimeter-wave (mmWave) communication technologies for multi-Gigabit wireless personal area networks (WPAN), aiming to support broadband multimedia applications. Internet Protocol TV (IPTV) is an emerging killer application which requires high data rate and stringent quality of services (QoS) in terms of delay and packet loss. In this paper, we propose a method to efficiently support high definition video flows in a mmWave-based WPAN with QoS guarantee, considering the characteristics of both the IPTV traffic and the mmWave communication technology. We first quantify the effective bandwidth of IPTV video sources using a simple, two-level Markov traffic model. Considering the overheads of the protocol stack in mmWave WPANs, we then quantify the minimum channel time needed for each IPTV flow. Since mmWave-based WPANs will deploy directional antennas to not only extend the transmission range, but also reduce the interference level to neighboring flows, we further propose an admission control scheme and scheduling algorithm to improve the network resource utilization by taking advantage of concurrent transmissions. Extensive simulations with NS-2 using real video traces have validated our analysis and demonstrated the efficiency and effectiveness of the proposed schemes, which will be an enabling technology for future mmWave-based WPANs supporting IPTV services. Part of this work was presented at 2008 Int. Conf. Heterogeneous Networking for Quality, Reliability, Security and Robustness (QShine’08), Hong Kong, July 2008. This work has been supported by research grants from the Natural Sciences and Engineering Research Council (NSERC) of Canada.     

互联网电视建设模式研究

本文结合国内视频业务发展情况,分析了OTT TV、IPTV发展情况,并对互联网电视的发展思路、产业链、发展模式进行了梳理,对比分析了几种互联网电视建设模式,并以广东公司建设模式为案例,介绍了该建设模式下互联网电视的建设方案。