its very difficult to FTP data(BIGfile) to backup server without using HTTP protocol in a web application.

Lets say, S1-( Client Browser ), S2-(code container server), S3-(Files Backup server) and we want to upload 2gb file from s1 using FTP.

use case diagram This can be done by "JavaApplet" . we can embed uploader applet in webapplication. This applet will run inside browser sand box.
go through link  sample code for ftp using applet

provided you have to enable java on your browser.

its very difficult to FTP data(BIGfile) to backup server without using HTTP protocol in a web application.

Lets say, S1-( Client Browser ), S2-(code container server), S3-(Files Backup server) and we want to upload 2gb file from s1 using FTP.

use case diagram

This can be done by "JavaApplet" . we can embed uploader applet in webapplication. This applet will run inside browser sand box.
go through link 

sample code for ftp using applet

provided you have to enable java on your browser.