Secure File Transfer Protocol (SFTP)
Secure File Transfer Protocol (SFTP), and Secure Copy (SCP), are utilities for securely transferring files between different sites over the Internet. In many ways, SFTP and SCP are interchangeable, but they are still unique processes. The implementations of SFTP and SCP on Windows, Linux, and Mac OS systems vary in method, and are described individually below.
Security Considerations
In most situations, such as when authentication is required (i.e. whenever you are asked for your password), SFTP should always be used as opposed to FTP to transfer files. Regular FTP sends your username, password, and other information across the network in clear text format. This makes it very easy for others to detect your information, and use it to do sinister things to your account and the network. SFTP and SCP work very similarly and just as easily, but provide securely encrypted (using SSH) file transfer.
SFTP/SCP on CAEN Windows Computers
All CAEN Windows machines are equipped with the Secure File Transfer Client from SSH Communications Security Corp. You can find it at:
Start >> Programs >> Communication Tools >> SSH Secure Shell
This is a useful tool for transferring files to/from your AFS home directory. This is done by connecting to the pool of Linux login servers. Simply start the program and hit the Quick Connect button. Enter the Host Name you want to connect to (e.g. login.engin.umich.edu or sftp.itd.umich.edu), your U-M uniqname as the User Name, and click Connect:
You will then be prompted for your password. Enter your ITCS (UMICH.EDU) Kerberos password.
As with many common SFTP programs, you will be presented with a split window; one side displaying files/folders on your local computer, and the other side displaying the files/folders on the remote server (in this case, in your AFS home directory). Files can be copied to/from each location by simply dragging and dropping their icons from one side to the other:
More information on the Secure File Transfer Client can be found in the Help menu. It is available for free download for personal use at:
SFTP/SCP on CAEN Linux Computers
SFTP and SCP can be invoked using command-line tools by typing sftp or scp at any CAEN Linux prompt. For example, If you wanted to copy a file in your home directory to your AFS Public directory, you could use scp as follows:
example% scp ~/file sftp.itd.umich.edu:Public/file
scp is also very useful because you can copy files from one remote machine to another:
example% scp host1:file1 host2:file2
So, if you want to copy a file from the temporary directory on example.engin.umich.edu to your AFS home directory, you could type:
example% scp example.engin.umich.edu:/tmp/filename sftp.itd.umich.edu:filename
Note: When you log into any CAEN Linux machine, you are taken to your ITCS IFS home directory by default. So, if the file you want to copy from, or the location you want to copy to, are not in your home directory tree, you will need to give the full path to the filename. For more information on the usage of these commands, type man scp or man sftp at the prompt.
SFTP/SCP on Mac OS
Mac OS has built-in, command-line SFTP and SCP programs that can be executed from the Terminal prompt (type man sftp or man scp for more information). In addition to these command-line tools, U-M has developed a graphical SFTP program for Mac OS called Fugu:
Fugu works like many common SFTP programs, but also has many unique features. More information about Fugu can be found in the Help menu. It is also available for free download for personal use at:
Other Popular SFTP/SCP Programs
Another popular SCP client for Windows is WinSCP:
WinSCP works like many common SFTP and SCP programs. More information about WinSCP can be found in its Help menu. It is available for free download as an installation package and a standalone executable at:
