BitTorrent中稀有段的传染病动力学建模与控制
Modeling and Control of Rare Segments in BitTorrent with Epidemic Dynamics
摘要：
尽管现有的激励措施leecher合作，BitTorrent文件共享基本上依赖于种子同行的存在。播种者对等体基本上在BitTorrent激励机制之外运行，但有两个警告：缓慢的下行链路会导致“临时”播种者数量的增加（他们离开了控制台，但当他们返回时会终止他们的播种者角色），以及文件分割为永久播种者提供的版权责任福利。使用两部分BitTorrent群的简单流行病模型，我们重点关注BitTorrent规则，首先传播（本地）最稀有的片段。与我们的模型，我们表明，稀有段第一规则最大限度地减少过渡时间播种（完整的文件采集），并均衡稳定状态下的段人口。我们讨论如何替代传播规则可能{ \em有益地增加}文件采集时间，导致水蛭留在系统中更长的时间（特别是作为临时种子）。其结果是，吸血鬼被进一步引诱合作。这消除了稀有片段灭绝的威胁，而稀有片段灭绝的威胁是通过永久播种者的存在来防止的。我们的模型使我们能够研究相应的性能改进之间的权衡，负载的永久播种机，和内容的可用性，我们留给未来的工作。最后，解释两段模型，一个涉及一个罕见的段和一个“集总”段代表其余的，我们研究了一个模型，共同考虑控制罕见的段和不同的上行链路造成“窒息”，高上行链路同行将不会从事某些交易与低上行链路同行。
英文摘要：
Despite its existing incentives for leecher cooperation, BitTorrent file sharing fundamentally relies on the presence of seeder peers. Seeder peers essentially operate outside the BitTorrent incentives, with two caveats: slow downlinks lead to increased numbers of "temporary" seeders (who left their console, but will terminate their seeder role when they return), and the copyright liability boon that file segmentation offers for permanent seeders. Using a simple epidemic model for a two-segment BitTorrent swarm, we focus on the BitTorrent rule to disseminate the (locally) rarest segments first. With our model, we show that the rarest-segment first rule minimizes transition time to seeder (complete file acquisition) and equalizes the segment populations in steady-state. We discuss how alternative dissemination rules may {\em beneficially increase} file acquisition times causing leechers to remain in the system longer (particularly as temporary seeders). The result is that leechers are further enticed to cooperate. This eliminates the threat of extinction of rare segments which is prevented by the needed presence of permanent seeders. Our model allows us to study the corresponding trade-offs between performance improvement, load on permanent seeders, and content availability, which we leave for future work. Finally, interpreting the two-segment model as one involving a rare segment and a "lumped" segment representing the rest, we study a model that jointly considers control of rare segments and different uplinks causing "choking," where high-uplink peers will not engage in certain transactions with low-uplink peers.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
