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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  TCP/IP Key Applications and Application Protocols            9  TCP/IP File and Message Transfer Applications and Protocols (FTP, TFTP, Electronic Mail, USENET, HTTP/WWW, Gopher)                 9  TCP/IP General File Transfer Protocols (FTP and TFTP)

FTP Sample User and Internal Command Dialog 1 TFTP Overview, History and Standards

The File Transfer Protocol (FTP) implements a full set of command and reply functionality that enables a user to perform a wide range of file movement and manipulation tasks between two TCP/IP machines. It is ideal as a general purpose protocol for file transfer between computers, but on certain types of hardware, it is too complex to easily implement, and provides more capabilities than are really needed. In cases where only the most basic file transfer functions are needed and simplicity and small program size is of paramount importance, a companion to FTP was created called the Trivial File Transfer Protocol (TFTP).

In this section I provide a description of the operation of TFTP. I begin with an overview description of the protocol, its history and motivation, and the relevant standards that describe it. I discuss its operation in general terms and how TFTP clients and server communicate, and explain TFTP messaging in detail. I then discuss TFTP options and the TFTP option negotiation mechanism, and conclude by showing the various TFTP message formats.

FTP Sample User and Internal Command Dialog 1 TFTP Overview, History and Standards