Understanding P2P File Sharing

P2P file sharing software reached its peak in the early 2000s

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The term P2P refers to peer-to-peer networking. On a peer-to-peer network, computer hardware and software communicate without the need for a server. Peer-to-peer file sharing is the distribution of digital media over a P2P network, in which the files are located on individual computers and shared with other members of the network, rather than on a centralized server. P2P software was the piracy method of choice in the early 2000s until a Supreme Court decision in 2005 led to the closure of many sites that illegally shared copyrighted material, mostly music.​

Rise and Fall of P2P File Sharing

P2P file sharing is used by file-sharing software clients such as BitTorrent and Ares Galaxy. P2P technology helps P2P clients upload and download files over the P2P network services. Many of the popular file-sharing software programs for P2P file-sharing are no longer available. These include:

  • Kazaa and Kazaa Lite were part of a popular line of file-sharing programs that dominated in the early 2000s.
  • Limewire was a cross-platform file-sharing software that was legally blocked because it was used to illegally share music. 
  • WinMx was the top source for online music in 2005. It survived various attacks and one closure only to see its user base shrink over time. This Windows-only software is mostly defunct.
  • eDonkey/Overnet was closed in 2005, although some users still access it through eMule.
  • Morpheus P2P software is no longer supported, but it is available as a free download online. It is used with Gnutella and BitTorrent clients. 
  • BearShare morphed into iMesh for a while following the 2005 Supreme Court decision. It was re-released as BearShare again, but it is no longer available for download.

Risks of Using P2P File Sharing

There are a number of personal and legal risks to consider before using P2P for file sharing:

  • Identify theft. Personal information has been shared and stolen through P2P networks including names, birthdates, and Social Security numbers. 
  • Legal risks. It's illegal to share copyrighted material. File sharing is legal when the sender has permission to share the material or when the material is in the public domain.
  • Privacy. P2P file-sharing offers no expectation of data privacy.
  • Protection. Exposure to trojans and viruses embedded in shared files is high.

P2P Networking vs P2P File Sharing

P2P networks are more than P2P file-sharing software. P2P networks are popular in homes where a dedicated server computer is neither necessary nor practical. P2P technology can also be found in other places. Microsoft Windows XP Service Pack 1, for example, contains a component called Windows Peer-to-Peer Networking.