an experienced user provide assistance to a less experienced one. User classification Users participating in P2P systems can be classified in different ways. According to Vassileva, users can be classified depending on their participation in the P2P system. There are five types of users to be found: users who create services, users who allow services, users who facilitate search, users who allow communication, users who are uncooperative and free ride. In the first instance, the user creates new resources or services and offers them to the community. In the second, the user provides the community with disk space "to store files for downloads" or with "computing resources" to facilitate a service provided by another users. In the third, the user provides a list of relationships to help other users find specific files or services. In the fourth, the user participates actively in the "protocol of the network", contributing to keeping the network together. In the last situation, the user does not contribute to the network, downloads what he or she needs but goes immediately offline once the service is not needed anymore, thus free-riding on the network and community resources. Tracking Corporations continue to combat the use of the internet as a tool to illegally copy and share various files, especially that of copyrighted music. The Recording Industry Association of America (RIAA) has been active in leading campaigns against infringers. Lawsuits have been launched against individuals as well as programs such as Napster in order to "protect" copyright owners. One effort of the RIAA has been to implant decoy users to monitor the use of copyrighted material from a firsthand perspective. Risks In early June 2002, Researcher Nathaniel Good at HP Labs demonstrated that user interface design issues could contribute to users inadvertently sharing personal and confidential information over P2P networks. In 2003, Congressional hearings before the House Committee of Government Reform (Overexposed: The Threats to Privacy & Security on File Sharing Networks) and the Senate Judiciary Committee (The Dark Side of a Bright Idea: Could Personal and National Security Risks Compromise the Potential of P2P File-Sharing Networks?) were convened to address and discuss the issue of inadvertent sharing on peer-to-peer networks and its consequences to consumer and national security. Researchers have examined potential security risks including the release of personal information, bundled spyware, and viruses downloaded from the network. Some proprietary file sharing clients have been known to bundle