基于加密的BitTorrent系统间接激励机制  

Encryption-based indirect incentive mechanism in BitTorrent

作　　者：张红梅[1] 齐法制[1] 满金贵[2] 王淼[2,3] 

机构地区：[1]中国科学院高能物理研究所计算中心,北京100049 [2]中国科学院计算技术研究所网络技术研究中心,北京100190 [3]中国互联网络信息中心互联网基础技术开放实验室,北京100190

出　　处：《计算机应用》2012年第9期2391-2394,2404,共5页journal of Computer Applications

基　　金：国家自然科学基金资助项目(61100177,61173133)

摘　　要：针对BitTorrent系统中的节点剥削行为,提出一种流模型论证剥削行为对系统性能的影响,通过该模型得到"剥削容忍阈值",当系统中剥削节点的比例超过该阈值时,系统可能"死亡"。为避免系统"死亡",提出一种基于加密的间接激励机制。在该机制中,节点必须经过一段时间的供种才能够获取密钥,还原下载的文件,同时该机制还能够根据节点的供种贡献对其下载行为进行奖励。实验结果证明:BitTorrent系统中节点不会因其供种行为获得任何奖励,无法达到抑制剥削行为的效果;引入所提出的机制后,供种节点的下载效率是原BitTorrent系统的2～3倍。In order to deal with exploiting in BitTorrent system, a fluid model was proposed to evaluate the effect of exploiting in BitTorrent system. With this model, the exploiting tolerance threshold can be obtained. When the ratio of exploiters exceeds this threshold, the system may die. To avoid the system dying, an Encryption-based Indirect Incentive Mechanism （EIIM） was proposed, in which a downloader must seed for a while before it can obtain the key to deerypt the file received. Also EIIM can give more download bandwidth to those nodes that provide more upload bandwidth to others. The simulation results show that BitTorrent system without EIIM cannot restrain exploiting. With EIIM, the seeders in BitTorrent system can get 2 -3 times download efficiency than those without EIIM.

关 键 词：BITTORRENT 流模型 剥削容忍阈值 文件加密 间接激励 

分 类 号：TP393.07[自动化与计算机技术—计算机应用技术]