Download SSH client. After installation, you will find a secure shell client and a secure file transfer client on your desktop. They can be taken as the secured version replacement for telnet and FTP. To log in or to do a file transfer to the department server, you connect to “stat.columbia.edu”.

• “ssh username@stat.columbia.edu” is the secure remote login command.
• “sftp username@stat.columbia.edu” is the secure file transfer command.
• The underlying operating system of Mac OS X is based on BSD Unix, which has built-in ssh support. The command line is identical to the UNIX commands mentioned above.

By default, your mail including your inbox and saved mail folders cannot be accessed by others.

• All other files can not be altered by others but can be seen by others if they correctly guessed your filenames including the entire path.
• You can change file/folder protection mode with the command “chmod”. You can learn how to use it by the command “man chmod”.
• If you don’t want others to read any of your files, put “umask 077” in your startup file, and run “chmod -R go-rx *” once.
• To make your homepage still available to others, run “chmod og+rx public_html” afterwards.

Download and use the secure shell client (ssh) to upload files from your PC to the Department server, you will also need to configure it to make sure your uploaded files won’t be readable by others. To do that, in the SSH Secure Shell client:

• Click Edit -> Settings, look for “File Transfer” part on the left, then click “Advanced” beneath it
• Then, on the right part, change “Default file permissions” to 600, and change “Default directory permissions” to 700
• Click OK. Click File -> Save Settings