FTP is a very insecure protocol because all passwords and all data are transferred in clear text. By using TLS, the whole communication can be encrypted, thus making FTP much more secure. This article explains how to set up ProFTPd with TLS on a Debian Etch server.

http://www.howtoforge.com/proftpd-tls-debian-etch

Vsftpd is one of the most secure and fastest FTP servers for Linux. Usually vsftpd is configured to work with system users. This document describes how to install a vsftpd server that uses virtual users from a MySQL database instead of real system users. This is much more performant and allows to have thousands of ftp users on a single machine.

http://www.howtoforge.com/vsftpd_mysql_debian_etch

This document describes how to install a PureFTPd server that uses virtual users from a MySQL database instead of real system users. This is much more performant and allows to have thousands of ftp users on a single machine. In addition to that I will show the use of quota and upload/download bandwidth limits with this setup. Passwords will be stored encrypted as MD5 strings in the database.

http://www.howtoforge.com/debian_etch_virtual_hosting_pureftpd_mysql_quota

This document describes how to install a Proftpd server that uses virtual users from a MySQL database instead of real system users. This is much more performant and allows to have thousands of ftp users on a single machine. In addition to that I will show the use of quota with this setup.

Virtual Hosting With Proftpd And MySQL (Incl. Quota) On Debian Etch

Proftpd is an excellent FTP server with many features. Wouldn't it be nice to see who is connected to your FTP server and what they are doing all in a convenient web-interface? phpftpwho allows you to see who is accessing your Proftpd FTP server all in a convenient web-interface. It is simple to install and only requires Proftpd, Apache, and PHP.

http://www.howtoforge.com/proftpd_monitoring_phpftpwho