Peer-to-Peer (P2P) systems do not operate on secure lines, thus providing a conduit for hackers to enter a network or computer, access personal and confidential information, as well as deploy viruses or worms. Users of P2P systems are prime targets and/or launching points for malicious hacker attacks simply because it requires downloading and sharing electronic files or programs, not to mention usage on publicly open and interpretable industry standard protocols and industry standard codec.
A Staff Report submitted by the Government Reform Committee of the U.S. House of Representatives (May 2003), entitled "File-Sharing Programs and Peer-to-Peer Networks - Privacy and Security Risks", stated that users of these programs have inadvertently made their personal information available to other users. "A search of one P2P network found at least 2,500 Microsoft Money backup files, which stores the users' personal financial records, available for download."
Personal information includes tax returns containing you name, address, and social security numbers of not only you, but your spouse and dependents, financial information such as income and investments, medical records, business files such as contracts and personnel evaluations, and attorney-client communications, to name a few.
Spyware and adware programs are frequently bundled into P2P file-sharing software. These programs collect personal information for marketers and provide access to your computer by malicious hackers. In an article located on Vnunet.com entitled "Users Fume at Grokster 'Drive-by Download'", these two programs "?can redirect a user's homepage to a different website, install a new browser toolbar, insert entries into the users' browser bookmark list, reinstall itself after uninstallation, and ultimately crash a user's system."
Another grave concern for both individuals and businesses when using P2P software is unknowingly having your computer used as a supernode. A supernode occurs when your computer is arbitrarily assigned as a hub.
When you are running the software for P2P services, your computer's disk space, bandwidth, and processing power are used to help other users on the same system operate their software more efficiently because of their own network or firewall constraints.
Not only can this overload systems or networks with excessive data, disk space, and network bandwidth, unscrupulous hackers can also insert arbitrary code in each supernode's address space or crash all supernodes.
Peer-to-Peer (P2P) systems such as Skype operate by taking bandwidth (information carrying capacity) from customers on their service to assist other customers using their service - analogous to a symbiotic relationship. The tools that enable them to accomplish this are bundled in the software their customers download to access their VoIP service.