Can anyone FTP into my PC, and how can I safeguard against this?

Note: The following information addresses an old security risk. Currently, you must set up your computer as an FTP or WWW server to risk FTP vulnerabilities. For more information about setting up an FTP server, see the following Knowledge Base documents:

• At IU, can I set up an anonymous FTP site?
  
  
• How do I set up Windows 2000 or XP Professional to accept FTP transfers?

Note: The software discussed here is no longer in common use at Indiana University, and UITS may no longer be able to verify the document's accuracy. The UITS Support Center may no longer have the manuals and other materials required to support this software adequately.

If your PC has been assigned an IP number, it may be possible for anyone to FTP into your computer, unless you take steps to safeguard against it. If you are on the Ethernet, you have an IP number; if you dial in using PPP, your PC will be assigned a temporary IP number. In either case, whether or not anyone can FTP into your computer depends on what TCP/IP software you're running, and how it's configured:

• If you're using LAN WorkPlace, the only way to allow FTP connections to your computer is to use the DOS or Windows FTP.
  
  
• If you're using the PC/TCP package (or the DCE telnet package), the FTP server is disabled by default when running telnet.
  
  
• If you're using the shareware NCSA or Clarkson packages, put the following line into your config.tel file: ftp=no

  If you don't do this, then anyone on the entire Internet could log into your computer.

You can also enable FTP in any of the above packages, and create a password file which permits access only to people you specify. You effectively give them usernames and passwords, specific to your PC's FTP server.

Also see:

• What is anonymous FTP?
• With FTP from DOS, how do I transfer files?
• With command line FTP, how can I transfer a group of files without typing out all their names?