A Measurement Study of Peer-to-Peer File Sharing Systems

http://www.cs.toronto.edu/~stefan/publications/mmcn/2002/mmcn.html

At this link, you can find an interesting research on a measurement of peer-peer sharing systems, namely Napster and Gnutella. In that paper, researchers illustrate the infrastructure of the systems as well as the topology of the Gnutella Network (as of February 16, 2001). According to the results of the research, they reach this interesting conclusion:

“Another myth in P2P file-sharing systems is that all peers behave equally, both contributing resources and consuming them. Our measurements indicate that this is not true: client-like and server-like behavior can clearly be identified in the population. As we have shown, approximately 26% of Gnutella users shared no data; these users are clearly participating to download data and not to share. Similarly, in Napster we observed that on average 60-80% of the users share 80-100% of the files, implying that 20-40\% of users share little or no files.”