free music downloads

File sharing is the practice of making files available for other users to download over the Internet and smaller networks. Usually file sharing follows the peer-to-peer (P2P) model, where the files are stored on and served by personal computers of the users. Most people who engage in file sharing are also downloading files that other users share. Sometimes these two activities are linked together. P2P File sharing is distinct from file trading in that downloading files from a P2P network does not require uploading, although some networks either provide incentives for uploading such as credits or force the sharing of files being currently downloaded.

The first P2P-Generation: Server-Client

The first generation of peer-to-peer file sharing networks had a centralized file list. Courts in the United States ruled that whoever controlled this centralized file list, containing works whose copyright was being infringed upon, were responsible for any infringement. Ultimately, Napster was held liable even if it used the most advanced technology available to identify works copyright holders had asked it to block, because no technology that can identify works with 100% certainty exists or can exist. Napster still exists today, but as a subsidiary of Roxio after they bought the name during the original Napster's bankruptcy phase, continues to operate today, and is now legally distributing music under a subscription-based model.

In the centralized peer-to-peer model, a user would send a search to the centralized server of what they were looking for, that is, song, video, movie. The server then sends back a list of which peers have the data and facilitates the connection and download.

The first file sharing programs marked themselves by inquiries to a server, either the data to the Download held ready or in appropriate different Peers and so-called Nodes further-obtained, so that one could download there. Best example was Napster (today a Payment offerer) or eDonkey2000 in the server version (today likewise with Overnet and KAD - network decentralized).

Sharehoster

Sharehoster for the file sharing are also used. Since it is here very well possible to exchange privately and in the very small framework also unpopular files can be distributed very fast and purposefully. Sharehoster are from each other independent, therefore contents are not offerer-spreading.

Server-client-protocols

• Audiogalaxy - Service ended in the middle of 2002.
• Direct Connect
• Napster - Closed in its original form in July 2001. Now it's a paid for service.
• Scour Exchange - The second exchange network after Napster. No longer exists.
• Soulseek - Still popular today despite being relatively old, with more than 120,000 users online at any time.
• TinyP2P - 15 lines Python - SOURCE code
• WinMX - The original servers were switched off in September 2005, but servers from other companies have taken over.

The second P2P-Generation: Decentralization

After Napster encountered legal troubles, Justin Frankel of Nullsoft set out to create a network without a central index server, and Gnutella was the result. Unfortunately, the Gnutella model of all nodes being equal quickly died from bottlenecks as the network grew from incoming Napster refugees. FastTrack solved this problem by having some nodes be 'more equal than others'.

By electing some higher capacity nodes to be indexing nodes, with lower capacity nodes branching off from them, FastTrack allowed for a network that could scale to a much larger size. Gnutella quickly adopted this model, and most current peer-to-peer networks implement this design, as it allows for large and efficient networks without central servers.

Also included in the second generation are distributed hash tables (DHTs), which help solve the scalability problem by electing various nodes to index certain hashes (which are used to identify files), allowing for fast and efficient searching for any instances of a file on the network. This is not without drawbacks; perhaps most significantly, DHTs do not directly support keyword searching (as opposed to exact-match searching).

The best examples are Gnutella, Kazaa or eMule with Kademlia, whereby Kazaa has still a central server for logging in. eDonkey2000/Overnet, Gnutella, FastTrack and Ares Galaxy have summed up approx. 10.3 million users (as of April 2006, according to slyck.com). This number not necessarily corresponds to the actual number of persons who use these networks; it must be assumed that some use multiple clients for different networks. The number of BitTorrent users cannot be measured directly, however, there should be more users than of eDonkey2000 and that's why providers try to restrict the BitTorrent traffic first. One must also understand that number of users indicated by software applies only to users which are active at this moment.

Multi-Network-Clients

• giFT
• Hydranode
• MLDonkey
• Morpheus
• Shareaza
• Lphant

eDonkey2000 - Network

• aMule
• eMule, usually-used Client
• FileScope
• Lphant
• MLDonkey
• Morpheus
• Overnet
• Shareaza
• xMule

Gnutella - Network

• Acqlite - Mac OS X
• Acquisition - Mac OS X, closed source (Shareware)
• BearShare - Microsoft Windows, closed source, development stopped in 2005,
• Cabos - Mac OS X and Microsoft Windows, based on LimeWire and Acquisition
• FileScope - .NET, open source (GPL), C#, also supports other networks
• FrostWire - open source (GPL), Java, based on LimeWire
• Gnotella - development stopped in 2001
• Gnucleus - Microsoft Windows, open source (GPL), C++, supports also Gnutella2
• Gtk-gnutella - Unix, open source (GPL), C
• I2Phex
• LimeWire - open source (GPL), Java
• MLDonkey - open source (GPL), Objective Caml, also supports other networks
• Morpheus - Microsoft Windows, closed source, also supports other networks
• Mutella - open source
• Phex - open source (GPL), Java
• Qtella - open source (GPL), development stopped in May 2004
• Shareaza - Microsoft Windows, open source, also supports other networks
• Symella - Symbian S60 v3, open source implementation for mobile platforms
• Swapper.NET - .NET, closed source, C#, development stopped in July 2004
• XoloX - contains adware/spyware

BitTorrent - Network

• Azureus - Multi-Platform Popular Client, pioneering the Zudeo service.
• BitComet - Windows, closed source, C++
• Shareaza - Windows, open source (GPL), C++, also supports Gnutella2, Gnutella1, eDonkey2000/eMule
• µTorrent - Windows, closed source, C++, light-weight client
• ABC - Windows, open source (GPL), Python
• Deluge (gTorrent) - GTK+, open source, Python
• eXeem - Stopped development in August 2005, contains adware
• KTorrent - KDE, open source (GPL)
• MLDonkey - platform-independent, open source (GPL), Objective Caml, also supports eDonkey2000/eMule, Overnet, Emule Kademlia, FTP, Gnutella1, Gnutella2
• Opera starting from version 9.0
• Rufus - Windows, open source, Python
• Tomato Torrent - Mac OS X, open source, BSD license
• Xtorrent - Mac OS X, only beta version is freeware
• Transmission - GTK+, platform-independent, open source (MIT License)
• Star Torrent - .NET, C#
• Tribler - platform-independent, open source (LGPL), Python
• BitRocket - Mac OS X (native), open source (BSD license)

See also: Comparison of BitTorrent software

Kazaa - Network

• Apollon - KDE, open source (GPL), based on Poisoned, also supports other networks
• Grokster - development stopped in June 2005
• Kazaa - official client, contains adware/spyware
• Kazaa Lite - derivative of Kazaa, contain no or less adware/spyware
• Mammoth - open source, development stopped in January 2004
• MLDonkey

Further networks or clients

• aimini
• Applejuice
• Ares Galaxy - nearly TRACKs - similar network
• Coral Content Distribution Network
• Darknet
• DC++ - Direct Connect client
• Dijjer
• Direct Connect
• Drumbeat - Mac OS X, OpenNAP client
• iMesh - since October of 2005 Payment offerers
• Jubster - client, supported networks: EDonkey2000, Gnutella, nearly TRACKs and further, contains adware
• JXTA
• Lopster - OpenNAP client
• Nicotine - Soulseek client
• OpenNap - Napster clone
• Peanuts - client, supported networks: Ares Galaxy, nearly TRACKs, Gnutella and further
• Piolet - client, successor of Blubster, network: MANOLITO P2P network (MP2PN)
• RevConnect - Enhanced DC++
• SlavaNap - Napster clone
• TekNap - OpenNAP client
• XDCC

The third P2P-Generation: non-direct and encrypted

The third generation of peer-to-peer networks are those that have anonymity features built in. Examples of anonymous networks are ANts P2P, RShare, Freenet, I2P, GNUnet and Entropy.

A degree of anonymity is realized by routing traffic through other users clients, which have the function of network nodes. This achieves resistance to analysis of who downloads what or offers which files. Most of these programs also have strong encryption to resist traffic sniffing.

Friend-to-friend networks only allow already known users (also known as "friends") to connect to your computer, then each node can forward requests and files anonymously between its own "friends" nodes.

Third generation networks have not reached mass usage for file sharing because most current implementations incur too much overhead in their anonymity features, making them slow or hard to use.

An example might be: Petra gives a file to Oliver, then Oliver gives the file to Anna. Petra and Anna thus never become acquainted and thus are protected. Virtual IP addresses are also often used, further obfuscating the user's network location. Additionally all transfers are encrypted, so that even the network administrators cannot see what was sent to whom. Example software includes WASTE, JetiANts, Tor and I2P. These clients differ greatly in their goals and implementation. WASTE is designed only for small groups and may therefore be considered Darknet, ANts and I2P are public Peer to Peer systems, with anonymization provided exclusively by routing reach.

Waste network

• WASTE
• kDrive similar to WASTE, development stopped at present

Ants network

• ANts P2P
• JetiANts
• Hornet

Mute network

• MUTE
• NapShare
• Kommute - KDE
• MFC MUTE

I2P network

• I2P
• I2Phex - Gnutella over I2P
• Azureus - has I2P plugin

other networks or clients

• Freenet
• GigaTribe - successor of TribalWeb software - [1]
• GNUnet
• Nodezilla
• Proxyshare - ISP cache/proxyserver
• RShare
• Share - successor of WinNY
• Tor
• WinNY - development stopped in November 2003
• Zultrax - Client, supported networks: ZEPP and Gnutella
• OFF System - so-called Brightnet [2]

The fourth P2P-Generation: Streams over P2P

Apart from the traditional file sharing there are services that send streams instead of files over a P2P network. Thus one can hear radio and watch television without any server involved -- the streaming media is distributed over a P2P network. It is important that instead of a treelike network structure a swarming technology known from BitTorrent is used. Best examples are Peercast, Cybersky and demo TV.

General

• Broadcatching
• Podcasting

Tree structure

• Peercast
• CoolStreaming

Swarm structure such as Bittorrent

• OMN
• Kedora
• Joost
• PPLive
• Icecast
• PeerCast
• PPStream
• SopCast
• MediaBlog
• TornadoTV
• Democracy
• Zudeo

Copyright issues

File sharing (such as with the Gnutella and Napster networks) grew in popularity with the proliferation of high speed Internet connections, relatively small file size and high-quality MP3 audio format. Although file sharing is a legal technology with legal uses, many users use it to download copyrighted materials without explicit permission: copyright infringement or "piracy". This has led to attacks against file sharing in general from some copyright owners.

There has been great discussion over perceived and actual legal issues surrounding file sharing. In circumstances where trading partners are in different countries with different legal codes, there are significant problems to contend with. What if a person in Canada wishes to share a piece of source code which, if compiled, has encryption capabilities? In some countries, a citizen may not request or receive such information without special permission.

Throughout the early 2000s, the entire file-sharing community has been in a state of flux. In the year 2000, there was speculation over how seriously record companies and the Recording Industry Association of America would strike the file-sharing community because of its limits compared to more traditional forms of media [3]. However, the communities suffered strain as record companies and the RIAA tried to shut down as much of it as possible. Even though they have forced Napster and Grokster into cooperating against copyright violations, they are fighting an uphill battle since the community has flourished and produced many different clients based on several different underlying protocols. The third generation of P2P protocols, such as Freenet, are not as dependent as Napster is on a central server; and as they encrypt the shared data, it is much harder to shut down these systems through court actions. Another attempt (used by the maintainers of KaZaA) is to change the company's organization or country of origin so that it is impossible or useless to attack it legally. To date, file sharing in Canada is somewhat legal, though not completely so[4]. The uphill battle also extends to the legal actions taken by the RIAA and motion picture counterpart MPAA against individuals using file-sharing programs to distribute material protected by copyright. Ambiguity in the interpretation of copyright law has been a major factor contributing the lack of successful enforcement by the Intellectual Property owners. In Electra v. Perez for example, the Court ruled that the act of making such files available for distribution equated to infringement of the works involved. In the more recent UMG v. Lindor, Judge David G. Trager ruled that the RIAA would be required to prove that actual distribution (sharing) occurred. Should this case go to trial in 2007, it will likely set a precedent for further RIAA and MPAA actions.

The Electronic Frontier Foundation (EFF) is a donor-supported group which seeks to protect and expand digital rights. Its activities include litigation, political lobbying, and public awareness campaigns. The EFF has vocally opposed the RIAA in its pursuit of lawsuits against users of file sharing applications and supported defendants in these cases. The foundation promotes the legalization of peer-to-peer sharing of copyrighted materials and alternative methods to provide compensation to copyright holders.^[1]

Risks

Some file sharing software comes bundled with malware such as spyware or adware. Sometimes this malware remains installed on the system even if the original file sharing software is removed, and can be very difficult to eliminate. In many cases such malware can interfere with the correct operation of web browsers, anti-virus software, anti-spyware and software firewalls, and can cause degraded performance on affected systems. Such malware is typically bundled with proprietary software, and not those in open source. In most cases it is possible to easily remove adware and spyware by running spyware removal programs. Such programs can often remove malware without influencing the functionality of the file sharing software.

Some are also concerned about the use of file sharing systems to distribute child pornography, inflammatory literature, and illegal or unpopular material. Novice users may find it difficult to obtain information on which networks are "safe" for them to use. However, experienced users know that there is only one way to get in contact with such material: You have to actively search for it.^[2] Therefore they recommend not to search for illegal material.