Measurement and understanding of Cyberlocker URL-sharing sites: Focus on movie files

Recently, Cyberlocker services have gained great popularity in the file-sharing market. Driven by tremendous benefits a large number of files such as popular movies are uploaded to Cyberlockers. We explore the profit chain of file-sharing networks based on Cyberlockers and find that an important issue is how to collect the download URLs of popular files stored at different Cyberlockers and share them with public users. In this paper, we focus on these sites collecting and sharing the Cyberlocker URLs of movies, called Cyberlocker URL-sharing sites. First, we extract 1,587 URL-sharing sites based on 31,525 valid pages returned by Google search and demonstrate that the quality distribution of these sites follows a power-law. Second, we analyze the link citations among URL-sharing sites and build the directed link citation graph. By characterizing basic metrics of the graph, such as cited strength and in/out-degree, we understand the structure of URL-sharing sites in depth. Furthermore, we discover that Cyberlocker URLs can be disseminated dynamically through crawler mechanisms among different sites, and highlight the implications of such metrics in this context. Additionally, we study the security risks of 1,587 URL-sharing sites. The results show that security risks do exist when surfing 155 suspicious URL-sharing sites such as myrls.me and rapid4me.com although the majority sites (90.23%) are safe. Finally, some preliminary suggestions are discussed from the industry point of view for how to improve the effectiveness of searching, collecting and disseminating Cyberlocker URLs. To the best of our knowledge, this is the first work on the measurement and understanding of Cyberlocker URL-sharing sites.