Shell Programming and Scripting

I would kindly request if somebody can brief me on this sftp script:

I have a regular ftp script;

HOST='ftp.server.com'
USER='RubinPat'
PASSWD='myname'
ftp -in $HOST <<END_SCRIPT
quote USER $USER
quote PASS $PASSWD

bi
get file.txt

Now my requirement is to create a sftp script. As per suggestion I created a .netrc file but that is not allowed. I have never done a sftp script before so am grooping in the dark. Can somebody tell me am I supposed to create a .ssh file or something....is sftp very much different than regular ftp as per coding is concerned........I tried the man page but there is no direction. Can somebody just write me the steps or guide me please? Thanks,

With ssh ie. sftp you should generate a public and private keypair (ssh-keygen, without entering a passphrase) and exchange the public key to your needs with the other host (into it's .ssh/authorized_keys). Try a simple "ssh <host> ls" after setup and if this works you can go on to write your sftp script. It should be very similar to the ftp script. You can spare the .netrc on ssh/sftp - it does not apply.
Instead you can also use scp with the setup above. Advantage with ssh/scp/sftp is that you also have encrypted communication between the hosts.

There should be plenty examples for passwordless ssh/scp/sftp seachable with the search function of the forum.

Generate Key using ssh-keygen -t rsa, then a private and public key would be stored in the passed directory or by default under .ssh/id_rsa.pub , copy contents of public key and add these contents to destination server authorized_keys files.Finally write your sftp script.

Zaxxon and dinjo, Thanks for the information. Still I am stuck. Let me tell u what I did.
I typed in ssh-keygen -t rsa and thereby it came as below:
Enter file in which to save the key (/home/Rubin/.ssh/id_rsa):<i did n't enter anything here and press enter key>
Enter passphrase (empty for no passphrase):<i did n't enter anything here and press enter key>

Enter same passphrase again:<i did n't enter anything here and press enter key>

Now I have two files in my .ssh folder id_rsa and id_rsa.pub

How do I now copy contents of public key and add these contents to destination server authorized_keys files? Who will create the authorized keys? Actually I don't see the .ssh folder in the remote server. I only have the username and password to login to the remote server. Do I ask the remote server guys to create a .ssh folder for me and create the authorized keys for me. Please tell me. I am honestly confused since I haven;t done it before and couldn't make out from the other other posts or thru google search.

The other side needs to have ssh installed too of course.

Use ftp to copy the public key (id_rsa.pub) to the server. Login in to the server as RubinPat. In your home directory create a .ssh subdirectory if one does not already exist. Then cat the contents of id_rsa.pub into the file called authorized_keys

Code:

cat id_rsa.pub >> .ssh/authorized_keys