IRC flood

Internet Relay Chat Flooding/Scrolling on an IRC network is a method of disconnecting users from an IRC server (a form of Denial of Service), exhausting bandwidth which causes network latency ('lag'), or just disrupting users.

The first attacks generally used a modified IRC client or an application to flood a channel or a user.

Theoretically it can also be used to disconnect users, because the target client sends information back about what port is intended to be used during the DCC session.

Sending massive numbers of private messages to the victim, mainly from different connections called clones (see below).

This is exploitable by sending messages from multiple names, causing the target client to open many new windows and potentially swamping the user with boxes.