More sFTP Questions

All,
I am beginning to get a handle on the basics of SFTP, and now have some
more questions.

1. In all of the examples that I see, the login is specifed as
UserName@xxxxxxxxxxxxxx (or .net ... etc)
Do I need the Host Name here or can I use an IP address? The
customer I am doing this for does not have any DSN configured on the i
system.

2. For the batch command file, does it have to be in a specific directory
or can it be anywhere?

3. For the file to be transmitted, does it have to be in a specific
directory or can it be anywhere?

4. From what I have been able to find out, the session log is in print file
QPRINT in the QTEMP library for the job.
If I want to put it in a file, can I override the QRPINT file to a
data file? If not, can I use the CPYSPLF command to copy it to a file?

5. The customer will be dealing with multiple servers, but each
transmission will of course be to only one.
There will be only one user id doing the transmission.
Are the public keys for each server stored in the same directory?

Thanks,
.