SFTP from UNIX (AIX) to Windows 2000 server

Hi all,
I have to sftp a file (put) from AIX server to Windows 2000 server.
The question is Windows 200 server that i am using doesnt have any SFTP server , if so i know we need to install one.
The question here is for writing a sftp script that as to run everyday as part of cron job we need to generate a password less key using ssh-keygen if its unix and give the public key to other user and keep the private key on the machine that you are connecting to under . Is it same in windows as well.