应用层组播研究进展  

State-of-the-art in Application Layer Multicast Research

作　　者：叶保留[1] 李春洪[1] 姚键[1] 顾铁成[1] 陈道蓄[1] 

机构地区：[1]南京大学计算机软件新技术国家重点实验室,南京210093

出　　处：《计算机科学》2005年第6期6-10,53,共6页Computer Science

基　　金：国家重点基础研究发展计划(973)项目(2002CB312002);国家"八六三"高技术研究发展计划项目(2001AA113050)的资助

摘　　要：组播技术是一种针对多点传输和多方协作应用的组通信模型,有高效的数据传输效率,是下一代Internet应用的重要支撑技术。早期的组播技术研究试图在IP层提供组播通信功能,但IP组播的实施涉及到对现有网络基础设施的调整,因此,大规模应用受到限制。近两年来,随着Peer-to-Peer(P2P)研究的兴起,基于应用层的组播技术也逐渐受到广泛关注。应用层组播协议将组成员节点自组织成覆盖网络,在主机节点实现组播功能,为数据多点并发传输提供服务。将组播功能从路由器迁移到主机上能有效解决许多与IP组播有关的问题,但同时也带来了一些新的挑战。本文分析了目前应用层组播研究的主要内容及技术特点,描述了协议设计所涉及的关键技术及面临的主要挑战,总结了现有工作及相关进展。Multicast provides an efficient way for one-to-many and multi-party communication. It is a key technique for the next-generation Internet applications. The conventional work on multicast emphasizes on providing multicast mechanism in IP protocol layer. However, the deployment of IP multicast is constrained by the modification to the op- erational Internet infrastructure and is hampered by a lot of unsolved technical problems. In the recent two years, the research trend on Peer-to-Peer (P2P) gives new light on multicast, and Application Layer Multicast (ALM) begins to attract wide attention. ALM protocols organize a set of hosts into an overlay tree for data delivery and all multicast related functions are implemented within end system. The shift of multicast functions from routers to hosts has the potential to address most problems associated with IP multicast, but also presents new challenges. This paper analy- ses the characteristics of ALM research from distributed system perspective, describes the technologies and difficulties involved in ALM design, and summarizes current work and progress.

关 键 词：应用层组播 研究进展 Internet 组播技术 数据传输效率 网络基础设施 IP组播 组播功能 通信模型 多点传输 支撑技术 通信功能 组播协议 关键技术 协议设计 IP层 自组织 有效解 路由器 节点 主机 

分 类 号：TP393.4[自动化与计算机技术—计算机应用技术] TN919.8[自动化与计算机技术—计算机科学与技术]