面向混合网络的半覆盖组播路由协议  

Half Overlay Multicast Routing for Hybrid Networks

作　　者：林彤[1] 钱华林[1] 葛敬国[1] 牛广锋[1] 

机构地区：[1]中国科学院计算机网络信息中心

出　　处：《软件学报》2007年第10期2572-2583,共12页Journal of Software

基　　金：Supported by the Special Foundation of President of the Chinese Academy of Sciences under Grant No.KGCX2-YW-106 (中国科学院 院长特别基金)

摘　　要：组播已在多个协议层上分别实现,但现有协议仍未兼顾对灵活性与效率的共同需求.总的来说,硬件组播和IP组播较为高效,而覆盖组播则更为灵活.在混合网络中,底层技术的差异使这一问题变得更为突出.为此提出了一种动态自组织的半覆盖组播路由协议HOMR(half overlay multicast routing).该协议把基于组内区域广播的IP组播、基于地址端口转换的覆盖组播以及对各类硬件组播的调用融入单一的模型,在各层组播间按需转换.HOMR具有与全覆盖组播相似的灵活性,模拟实验表明,HOMR在保持较低协议开销的同时,获得了与完全IP组播相近的转发效率.Although multicast can be implemented in every layer of network, the existing multicast protocols rarely meet the demands both for flexibility and efficiency at one time. In general, hardware multicast and IP multicast are more efficient than overlay multicast, but the situation of flexibility is quite the contrary. This problem is much pressing in hybrid networks, in which the two demands have the same priority. This paper proposes a novel protocol named half overlay multicast routing that integrates IP layer in-group regional broadcast, address-and-port-translation based overlay multicast and extensible support for hardware multicast into one single model, where the three mechanisms are chosen dynamically for data delivery. By this approach, HOMR obtains the flexibility of overlay multicast. The simulation results show that the overhead of HOMR is low and the performance of HOMR is comparable with pure IP multicasting.

关 键 词：组播 路由协议 混合网络 半覆盖 自组织 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]