文档介绍：Classified Index:.: the Master Degree inEngineeringTHE OPTIMIZATIONTECHNIQUE OF CAN BASED OVERLAYCandidate:Taikang WooSupervisor:Prof. Zhang HongliAcademic Degree Appliedfor:Master puter Science and puter Science and TechnologyDate ofDefense:June, 2009Degree-Conferring-Institution:Harbin Institute of Technology哈尔滨工业大学工学硕士学位论文--I摘要P2P模式以其能更好的利用互联网中的计算能力、带宽、存储等资源,具有健壮性好、成本低、伸缩性强等优势,迅速地得到了广泛的推广和研究。本文遵循了结构化P2P的模型CAN(Content work)的基本思路,提出了定向多播、扩展的定向多播方法以及定向多播路由和路径冗余相结合的方法。这些方法相对于传统P2P模式在路由能力和效率上有所提高,并且有效地降低了系统的查询负载,并且提高了系统的可靠性。此外,本文深入的研究了基于多维逻辑空间的覆盖网上的失效恢复机制。为了有助于恢复机制的运作,设计了基于霍夫曼编码的对逻辑空间区域编码的机制。利用此机制对失效恢复过程进行指导,可以有效地恢复覆盖网的整体结构。实验表明,本文提出的覆盖网组织方式具备优秀的负载均衡性能;在定向多播路由方法和路径冗余方法的结合下,系统查询效率与传统的方法相比有明显提高;另外,系统在面对大量结点失效的时候,可以通过失效恢复机制得到迅速、准确的恢复。有效地解决了传统的恢复方法下,大量结点失效将导致覆盖网结构破坏甚至分裂的问题。关键词:分布式系统,结构化P2P;CAN;失效恢复机制哈尔滨工业大学工学硕士学位论文--IIAbstractThe P2P system has been widelystudied and used because it can efficiently make use of pute capability, bandwidthand storage capability of the , as well as it is stability, low cost and this paper, weproposedadirected-multicast routing method, extended directed-multicast routing method and design a bined both directed multicast routing and path redundancybyfallowingthespiritofCAN(Content work), witch is a structured peer to peer methodsimprove the performance of routing capability and efficiencyunder the traditional P2P model. It alsoreduces the system’s query load effectivelyand enhances the reliability of the , we have made anintensivestudy about the recovery mechanism about the overlay based on multi-dimensional order to support the recovery mechanism’s running, we designed a Huffman-based encoding methodto mark the zone of the logic methodis used toguide the recoveraboutthe failurezone, andcanrepair the whole logic space’s structure experimental results anizationmethod has an excellent load balance bination of both