As its name suggest, vsftpd (Very Secure FTP Daemon) is a secure and very fast FTP server. It is licensed under GNU GPL. vsftpd supports both explicit and implicit FTPs. vsftpd can handle many things such as Virtual IP configurations, standalone or inetd configuration, bandwidth trotting, etc. It supports IPv6 and also provides strong encryption through SSL integration. Per-source-IP configurability and Per-source-IP limits can also be done VIA vsftpd.