Inequity of Sharing Ratio Enhancement in Darknet: Measurement and Improvement

Private BitTorrent community (PT), as known as "BitTorrent Darknet", has become a popular research spot in recent years. PTs can provide ultra-high download performance which is much better than public BitTorrent communities. The Sharing Ratio Enhancement (SRE) mechanism is the key to PTs\´ success. However, it also brings negative side effects to the registered users in PTs. In this paper, we crawl and analyze all of user profiles from three influential PTs which provide very detailed information. We show that the sharing ratio of members cannot represent their upload contribution in terms of upload time and amount. Members are forced to seed for a long time to maintain adequate sharing ratios to survive in the community. SRE mechanism\´s nature drawbacks induce inequity. Based on these measurements, we propose a unified two-track payment system to pay peers based on their contribution, which is an alternative mechanism to SRE. We consider the payment with inflation and transit process. Our systems can provide a fair and consistent environment, which is helpful to unify and to build sustainable development of private BitTorrent communities.