The SBACKUP module provided with the UnixWare NLMs has a session logging feature that ensures that you insert the medium whose label corresponds to the session you select.
In other words, if you know that you want to restore last Friday's backup, you can open SBACKUP's session logging feature and choose the entry for Friday's backup session.
When you insert the medium to restore, SBACKUP will check the label on the tape (the one you gave it when you created the backup on Friday) and make sure it matches the label in the session log entry.
If the labels do not match, SBACKUP will abort the restore operation. You can also choose to restore a particular backup media without reference to the session log.