中国科学院软件研究所机构知识库
Advanced  
ISCAS OpenIR  > 中科院软件所  > 中科院软件所
题名:
交换式以太网上多媒体组播的研究
作者: 王军
答辩日期: 2003
专业: 计算机应用技术
授予单位: 中国科学院软件研究所
授予地点: 中国科学院软件研究所
学位: 博士
关键词: 可靠组播 ; 组播应用框架 ; 数字电视 ; 以太网 ; 组播技术
其他题名: Research of Multimedia Multicast in Switch Ethernet
摘要: 该文对交换式以太网中多媒体组播通信的机制进行了深入的研究,解决了宽带以太网接入环境中传统广播和新兴多媒体组播业务的有效传输和服务质量保证问题.该文的主要贡献和创新点如下:1.设计和实现交换式以太网中基于IGMPSnooping的二层组播协议.利用交换机的侦听功能,将IGMP报文中IP组播组所包含的主机群体对应到链路层组--VLAN的端口集上,利用终端和路由器或者智能交换机的IGMP协议模块管理VLAN组的动态加入和退出,结合交换式以太网中VLAN的组通信功能实现二层组播.2.提出并实现一种基于DLB的自适应整形算法.通过监视数据缓冲区和令牌缓冲区中有效长度的动态变化,在线估计通信量的输入速率和速率整形的输出效果,动态调整DLB的参数设置,使输出通信量在数据无丢失和最大延迟约束条件下达到最佳速率平滑效果.3.针对以太网低延迟、平坦拓扑和高可靠性的传输特点,提出和实现一种实时连续媒体流的可靠组播协议.最后,该文基于如上技术提炼综合出一个多媒体组播应用框架,为交换式以太网上的数字电视接入、MulticastStreaming和WebCasting等应用提供一个能够保证服务质量的多媒体组播应用平台,并且基于此框架提出和实现一个宽带综合业务社区网络系统的实现方案,其中的典型组播应用是数字电视接入服务.
英文摘要: The future of the "last-mile" belongs to Ethernet because of its low-cost, high-speed and powerful functions. The multicast technology makes it very easy to provide the broadcast TV service in computer network, and improves the development of collaboration applications and shared services. However, traditional Ethernet lacks the support for multicast services and multimedia real-time services. It leads to inefficient usage of network resource and provide no guarantee for the quality of services. Under such background, this dissertation makes the research in the mechanisms of multimedia multicast service in Switch Ethernet, and provides traditional broadcast TV and multimedia multicast applications with a total solution for the efficient transfer and guarantee of QoS. The following are the main contributions of this dissertation. The first is an IGMP-Snooping-based multicast protocol of link layer in Switch Ethernet. It maps a group of hosts in an IP multicast group to a group of ports in a VLAN, a communication group in link layer. The presented protocol manages the ports' dynamic join and exit to groups by the IGMP modules of hosts, router and switch, and makes the distribution of multicast data by VLAN of switch. Using this protocol, Switch Ethernet can provide the support for multicast service without any change in terminals and routers. This method not only saves the network bandwidth but also integrates the link layer multicast with IP multicast. The second is an adaptive traffic shaping algorithm based on DLB. This algorithm is used to smooth the traffic with a large fluctuation of output rate. It can estimate and compute the average input rate of the traffic online by monitoring the change of the length of the data buffer. It updates the settings of the traffic shaper depending on the rate changes of the source traffic so as to provide smoothed stream under limited resources. The algorithm presented in this thesis doesn't need to pre-analysis of the source traffic, so as to make it possible for online traffic shaping. The third is a reliable multicast protocol for real-time continuous- media streams on Switch Ethernet, which makes use of the Ethernet's characteristic of low-delay, flat topology and high-reliability. The acknowledgement and retransmission technology is used for the recovery of the lost packets; NAK suppression is used to address the NAK implosion problem; and limited retransmission by real-time playback avoids producing unused retransmission data. This protocol improves the effectiveness and reliability of the continuous media multicast streams under real-time playback. The reliability depends on the data pre-buffering time in receivers and the size of retransmitted buffer in senders. Overall, by combining the IGMP Snooping protocol, traffic shaping algorithm, reliable multicast and current IP multicast mechanism, this dissertation presents a framework for multimedia multicast applications in Switch Ethernet, to provide a service platform with guarantee of QoS for DTV access, Multicast Streaming and WebCasting, to provide an IP-based architecture for Broadband Integrated Service Community Network and finally to provide an implementation of a typical DTV access system based on this architecture.
语种: 中文
内容类型: 学位论文
URI标识: http://ir.iscas.ac.cn/handle/311060/7176
Appears in Collections:中科院软件所

Files in This Item:
File Name/ File Size Content Type Version Access License
LW011200.pdf(3283KB)----限制开放-- 联系获取全文

Recommended Citation:
王军. 交换式以太网上多媒体组播的研究[D]. 中国科学院软件研究所. 中国科学院软件研究所. 2003-01-01.
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[王军]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[王军]‘s Articles
Related Copyright Policies
Null
Social Bookmarking
Add to CiteULike Add to Connotea Add to Del.icio.us Add to Digg Add to Reddit
所有评论 (0)
暂无评论
 
评注功能仅针对注册用户开放,请您登录
您对该条目有什么异议,请填写以下表单,管理员会尽快联系您。
内 容:
Email:  *
单位:
验证码:   刷新
您在IR的使用过程中有什么好的想法或者建议可以反馈给我们。
标 题:
 *
内 容:
Email:  *
验证码:   刷新

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.

 

 

Valid XHTML 1.0!
Copyright © 2007-2017  中国科学院软件研究所 - Feedback
Powered by CSpace