EMule

In computing, eMule is a peer to peer file sharing application that works with the EDonkey Network network and offers more features than the standard eDonkey client. eMule is open source software released under the GNU General Public License. It runs on the Microsoft Windows operating systems.

The distinguishing features of eMule are the direct exchange of links between client nodes, fast recovery of corrupted downloads, and the use of a credit system to reward frequent uploaders. Furthermore eMule transmits data in (Zlib-)compressed form to save bandwidth. Another feature of eMule is the ability to accept "ed2k" links from a web browser and begin downloading the file(s) these links refer to. These links ensure that the file being downloaded is indeed what it says it is and does not contain a virus or spyware. Recently many of the sites which provide these links have been taken offline by authorities due to questionable legality of the links they provide.

Duplicate versions of the same file are identified through the use of the MD4 algorithm.

Recent versions (v0.40+) of eMule have their own implementation of the Kademlia-network, which does not rely on central servers as the eDonkey network does. Also added in recent versions were "Unicode Search" (allows searching for files in many languages) and the ability (not supported in Kademlia) to see in server search which files have complete sources (and can therefore be completely downloaded).

Because eMule is a popular open-source program, hundreds of eMule mods (modifications of the original eMule) have appeared on the Internet.

The eMule client is a Windows application; its code forms the basis for the Linux clients, xMule and aMule.

Large number of eMule users download files larger than 100 MB (complete audio disks or movies) and this leads to huge queues of up to 5000 users. Such queues make eMule very hard to use for MP3 exchange.

The most important feature of eMule is that it forces the user to share files, by two methods:

1. Downloaded files are divided and downloaded in parts, so that a recipient starts to share the parts of the file already downloaded even before the download is complete. The recipient is forced to share in this way until the download is complete.
2. If a user chooses to limit his upload rate, eMule will automatically decrease his download rate.

Although there are many mods of eMule, it is very hard to find one that doesn't enforce the second feature, which is a part of official eMule policy.

• Number of concurrent users: 3.5 - 5.1 million.
• Number of concurrent shared files: ~750 million.

See also

• Shareaza
• Gnutella
• BitTorrent
• Napster

External links

• eMule project
• eMule on SourceForge (SourceForge)