Downloading ubuntu images using S-FTP ?

[Jatin]

Hi List

I want to download the ubuntu images using SFTP. I tried using the TCP 
port 989 but its not working. I get the following error message on my 
FileZilla client:

Command:    open "anonymous at mirror.anl.gov" 989
Error:    Connection timed out
Error:    Could not connect to server

Please let me know how i can use SFTP to download the images.

Thanks
Jatin