Direct Connect (file sharing)

Direct Connect (DC) is a peer-to-peer file sharing . Direct Connect clients connect to a central hub and can download files directly from one another. Advanced Direct Connect can be considered a successor protocol.

Hubs feature a list of clients or users connected to them. Users can search for files and download them from other clients, as well as chat with other users.

NeoModus was started as a company funded by the adware "Direct Connect" by Jonathan Hess in November, 1999 while he was in high school.

The first third-party client was called "DClite", which never fully supported the file sharing aspects of the protocol. Hess released a new version of Direct Connect, requiring a simple encryption key to initiate a connection, locking out third-party clients. The encryption key was cracked, and the author of DClite released a new version of DClite compatible with the new software from NeoModus. Some time after, DClite was rewritten as Open Direct Connect with the purpose of having an MDI user interface and using plug-ins for file sharing protocols (similar to MLDonkey). Open Direct Connect also did not have complete support for the full file sharing aspects of the protocol, but a port to Java, however, did. Later on, other clients such as DCTC (Direct Connect Text Client) and DC++ became popular.

The DCDev archive contains discussions of protocol changes for development of DC in the years 2003-2005.

The Direct Connect protocol is a text-based computer protocol, in which commands and their information are sent in clear text, without encryption in original NeoModus software (encryption is available as a protocol extension). As clients connect to a central source of distribution (the hub) of information, the hub requires a substantial amount of upload bandwidth available.

There is no official specification of the protocol, meaning that every client and hub (besides the original NeoModus client and hub) has been forced to reverse engineer the information. As such, any protocol specification this article may reference is likely inaccurate and/or incomplete.

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