An important goal in peer-to-peer networks is that all clients provide resources, including bandwidth, storage space, and computing power. Thus, as nodes arrive and demand on the system increases, the total capacity of the system also increases. This is not true of a client-server architecture with a fixed set of servers, in which adding more clients could mean slower data transfer for all users.

The distributed nature of peer-to-peer networks also increases robustness in case of failures by replicating data over multiple peers, and -- in pure P2P systems -- by enabling peers to find the data without relying on a centralized index server. In the latter case, there is no single point of failure in the system.

When the term peer-to-peer was used to describe the Napster network, it implied that the peer protocol was important, but, in reality, the great achievement of Napster was the empowerment of the peers (i.e., the fringes of the network) in association with a central index, which made it fast and efficient to locate available content. The peer protocol was just a common way to achieve this.

Academic peer-to-peer network

Recently, developers at Pennsylvania State University, in conjunction with Massachusetts Institute of Technology Open Knowledge Initiative, researchers at Simon Fraser University, and the Internet P2P working group, have been working on an academic application for the peer-to-peer network. This project referred to as LionShare is based on a second generation network, more specifically the Gnutella model.

The main purpose of this network is to share academic material between users at many different academic institutions. The LionShare network is based on a hybrid model that mixes the Gnutella decentralized peer-to-peer network with a more traditional client-server network. Users of this program are able to upload files to a server where they can be shared continuously, regardless of whether or not the user is online. This network allows for a much smaller than normal sharing community.

The main difference between this network and virtually all other peer-to-peer networks is the fact that the users of LionShare will not be anonymous. The purpose of this is to deter the sharing of copyrighted material over the network, and thus avoid legal issues. Another difference is the ability to selectively share individual files with specific groups. A user is able to select on an individual basis which users are able to receive an individual file or group of files.

This technology is needed in the academic community because of the use of more and larger multimedia files in the classroom setting. More and more professors are using multimedia files such as audio, video and slide show. Transferring these files to students is a difficult task that would be made much easier by a network such as LionShare.