TFTP (Trivial File Transfer Protocol) is sometimes used to transfer configuration files from equipments such as routers but the primary difference between FTP and TFTP is that TFTP does not require authentication. Speed and ability to automate are not important.
Both of these protocols (FTP and TFTP) can be used for transferring files across the Internet. The differences between the two protocols are explained below:
FTP is a complete, session-oriented, general purpose file transfer protocol. TFTP is used as a bare-bones special purpose file transfer protocol.
FTP can be used interactively. TFTP allows only unidirectional transfer of files.
FTP depends on TCP, is connection oriented, and provides reliable control. TFTP depends on UDP, requires less overhead, and provides virtually no control.
FTP provides user authentication. TFTP does not.
FTP uses well-known TCP port numbers: 20 for data and 21 for connection dialog. TFTP uses UDP port number 69 for its file transfer activity.
The Windows NT FTP server service does not support TFTP because TFTP does not support authentication.
Windows 95 and TCP/IP-32 for Windows for Workgroups do not include a TFTP client program.
Ref: http://support.microsoft.com/kb/102737