Joomla-accounts will be created by joomla administrator.
The FTP-Accounts will be created by hand through Plesk Serveradministration.
The aim is, that users have the choice to use a FTP-Client i.e. Filezilla to login to their FTP-Account or login to Jommla and use the webbased ftp-client with the same account data.
The functionality of the ftp-client has to be very basic. Just up- and download of a number of files, create, rename and delete directories. No rights management, no preview. While up-/downloading a progressbar should be displayed.