This Knowledge Base article describes two enhancements in System Manager that are available with MicroStrategy 9.3.1 and newer
In Strategy 9.3.1, two enhancements have been made to the "Download Using FTP" process in System Manager.
Support for SFTP:
Use FTP: Encrypts the entire download communication. You must have a secure FTP site for this encryption to work successfully.
Support for specifying the Port Number of the FTP/SFTP Server.
Port Number: Select this option to specify a specific port number to access the FTP or SFTP site. If not checked, the default port number is used. By default, System Manager uses Port Number 22.