FTP uses the standard ftp port, 21 (ftp://ftp.fsn.hu/)
HTTP uses the standard webserver port, 80 (http://ftp.fsn.hu/)
rsync uses the tcp port 873 (rsync://ftp.fsn.hu/ftp/)

The HTTP server has directory listing disabled, so this way browsing the archive "through the web" (HTTP) is not possible.

If you want to download something using the HTTP protocol, just figure out its URL for FTP (for example: with FTP, ftp://ftp.fsn.hu/ls-lR) and replace the ftp:// string to http:// (http://ftp.fsn.hu/ls-lR).