Peer-to-Peer

Chapter 16. Accountability

Roger Dingledine, Reputation Technologies, Inc., Michael J. Freedman, MIT, and David Molnar, Harvard University

One year after its meteoric rise to fame, Napster faces a host of problems. The best known of these problems is the lawsuit filed by the Recording Industry Association of America against Napster, Inc. Close behind is the decision by several major universities, including Yale, the University of Southern California, and Indiana University, to ban Napster traffic on their systems, thus depriving the Napster network of some of its highest-bandwidth music servers. The most popular perception is that universities are blocking Napster access out of fear of lawsuit. But there is another reason.

Napster users eat up large and unbounded amounts of bandwidth. By default, when a Napster client is installed, it configures the host computer to serve MP3s to as many other Napster clients as possible. University users, who tend to have faster connections than most others, are particularly effective servers. In the process, however, they can generate enough traffic to saturate a network. It was this reason that Harvard University cited when deciding to allow Napster, yet limit its bandwidth use.

Gnutella, the distributed replacement for Napster, is even worse: not only do downloads require large amounts of bandwidth, but searches require broadcasting to a set of neighboring Gnutella nodes, which in turn forward the request to other nodes. While the broadcast ...