多点组播的可靠扩展控制机制研究

针对多点组播（multicast)控制机制中可靠性（reliability)与可扩展性（scalability)间存在的问题，将扩展性方案中超立方体（hypercube)拓扑思想与可靠性方案中反馈重发局部化（localization)思想用于控制机制，提出一种基于超立方体拓扑的可靠扩展控制机制：将组播节点控制拓扑从1维树型拓扑映射为n维超立方体拓扑，运用超立方体拓扑的几何特性将基于包丢失的局部反馈重发可靠性有效融于节点扩展性中，实现组播的有效可靠扩展。理论分析与实际测试表明：控制机制有着良好的扩展性和可靠性，可满足不同网络条件下的多点组播的可靠性扩展。

RESEARCH ON A RELIABLE AND SCALABLE MULTICAST CONTROL MECHANISM

Reliable and scalable multicast is an active research field of multicast in recent years. A hypercube based reliable & scalable multicast control mechanism is presented to solve the contradiction problem of multicast reliability and related scalability, which combines the hypercube geometric character of multicast reliable solution and the localization of multicast scalable solution. The mechanism is implemented by embedding the 1 dimension tree topology into n dimension hypercube topology and applying the local ARQ recovery to the hypercube topology. The experiments and tests are based on the MS Windows platform and 100M Ethernet LAN. According to the theory analysis and experiment results, the hypercube based reliable & scalable mechanism shows efficient reliability and high scalability (the reliablility will increase with the scalability of node numbers in the hypercube,which can achieve over 90% reliability with only 4 nodes.), which can fulfil the requirement of reliable & scalable multicast in different network environments.