Direct Client-to-Client (
DCC) is an
IRC-related sub-protocol enabling
peers to interconnect using an IRC server for
handshaking in order to exchange files or perform non-relayed chats. Once established, a typical DCC session runs independently from the IRC server. Originally designed to be used with
ircII it is now supported by many
IRC clients. Some peer-to-peer clients on napster-protocol servers also have DCC send/get capability, including TekNap, SunshineUN and Lopster. A variation of the DCC protocol called SDCC (Secure Direct Client-to-Client), also known as DCC SCHAT supports
encrypted connections. An
RFC specification on the use of DCC does not exist.