SFTP client for centos6

[Noturns]

I need some help with setting up an automated SFTP on centos6
because i would like to create a cronjob that syncs files

1. If someone could post an example SFTP batch file with specific SFTP port?
solved. found an article -- http://stackoverflow.com/questions/...sftp-command-with-a-password-from-bash-script
found port solution here -- http://www.linuxquestions.org/questions/linux-security-4/how-to-use-different-port-for-sftp-345359/
found an alternative for open sftp (yafc) is an alternative solution which supports -r parameter for files and folders -- http://unix.stackexchange.com/questions/7004/uploading-directories-with-sftp

2. Explain passwordless authentication?
solved. found an article -- http://stackoverflow.com/questions/...sftp-command-with-a-password-from-bash-script
and found article -- http://www.linuxforums.org/forum/programming-scripting/108268-expect-spawn-command-not-found.html

3. Copy an local directory to SFTP directory?
solved. found an article -- http://stackoverflow.com/questions/...sftp-command-with-a-password-from-bash-script

4. How to parse date to a variable?
solved. found an article -- http://www.unix.com/shell-programming-and-scripting/26708-assign-date-value-variable.html

5. How to generate a logfile to that same SFTP directory?
not solved yet

Thanks