Server Software
The main server software used for eD2k network is known as Lugdunum server. It was created by reverse engineering edonkey protocol and redesigned from scratch. (MetaMachine abandoned development of eD2k server software and revealed the source code to Lugdunum in late 2002, but was never used). Lugdunum has extended the eD2k protocol while maintaining backward compatibility. Lugdunum server software is gratis, but not open source. The stated reason for not opening the source is to prevent the easy creation of fake servers and to prevent attacking the server itself.
In September 2007 a new server software was announced on the eMule web site forums, called satan-edonkey-server. Given the shut down of major eMule servers due to legal action against them just days earlier, the new server was accepted with suspicion. It was feared that the software may transmit information about the clients to unknown third parties. Some trusted eMule developers received the source code of satan-edonkey-server and stated that no spy-code is built in. The satan server software was created by reverse engineering edonkey protocol. The software comes in two versions (C++ and Java). Satan-eDonkey-server software is also gratis.
Read more about this topic: EDonkey Network