EDonkey2000

eDonkey2000 is a peer-to-peer file sharing application and the original network associated with it, released in 2000. The system operates by having user clients connect to a distributed network of servers that index and share lists of available files. When a user searches for a file, the request is sent to one or more servers, which return matching results. Actual data transfers occur directly between clients, rather than through a central server, making the network a decentralized, server-assisted P2P system. The protocol commonly used with this network is known as the ED2K protocol.

Architecture and protocol features include a server-based indexing model where many servers exist to aid discovery, while file transfers are peer-to-peer. The ED2K protocol defines search and transfer commands, supports file metadata exchange, and uses file-specific hashes for verification. Files are identified by their MD4 hash, and optional Tiger Tree Hashes (TTH) are used to verify integrity. Ed2k links encode file metadata to facilitate identification and sharing.

History and impact note that eDonkey2000 was one of the prominent P2P networks in the early 2000s, widely used for sharing music, software, and other media. The network faced legal challenges and competitive pressures, which led to changes in popularity and the rise of alternative clients and forks. In particular, open-source projects such as eMule emerged to continue using the same ED2K network while developing additional features and cross-platform support. The ecosystem also includes other clients that implement the same protocol, maintaining activity on the network through various communities.

Legacy: Although the original client’s active development waned, the ED2K network persists through forks and compatible clients, with eMule being among the best-known continuations and contributors to ongoing ecosystem viability. See also: ED2K protocol, eMule, MLDonkey, aMule.