Network Working Group                                         K. Sollins
Request For Comments: 1350                                           MIT
STD: 33                                                        July 1992
Obsoletes: RFC 783


                     THE TFTP PROTOCOL (REVISION 2)

Status of this Memo

   This RFC specifies an IAB standards track protocol for the Internet
   community, and requests discussion and suggestions for improvements.
   Please refer to the current edition of the "IAB Official Protocol
   Standards" for the standardization state and status of this protocol.
   Distribution of this memo is unlimited.

Summary

   TFTP is a very simple protocol used to transfer files.  It is from
   this that its name comes, Trivial File Transfer Protocol or TFTP.
   Each nonterminal packet is acknowledged separately.  This document
   describes the protocol and its types of packets.  The document also
   explains the reasons behind some of the design decisions.

Acknowlegements(略)

1. Purpose

   TFTP is a simple protocol to transfer files, and therefore was named
   the Trivial File Transfer Protocol or TFTP.  It has been implemented
   on top of the Internet User Datagram protocol (UDP or Datagram) [2]
   so it may be used to move files between machines on different
   networks implementing UDP.  (This should not exclude the possibility
   of implementing TFTP on top of other datagram protocols.)  It is
   designed to be small and easy to implement.  Therefore, it lacks most
   of the features of a regular FTP.  The only thing it can do is read
   and write files (or mail) from/to a remote server.  It cannot list
   directories, and currently has no provisions for user authentication.
   In common with other Internet protocols, it passes 8 bit bytes of
   data.

   Three modes of transfer are currently supported: netascii (This is
   ascii as defined in "USA Standard Code for Information Interchange"
   [1] with the modifications specified in "Telnet Protocol
   Specification" [3].)  Note that it is 8 bit ascii.  The term
   "netascii" will be used throughout this document to mean this
   particular version of ascii.); octet (This replaces the "binary" mode
   of previous versions of this document.) raw 8 bit bytes; mail,
   netascii characters sent to a user rather than a file.  (The mail
   mode is obsolete and should not be implemented or used.)  Additional
   modes can be defined by pairs of cooperating hosts.

   Reference [4] (section 4.2) should be consulted for further valuable
   directives and suggestions on TFTP.

(以下，略)

References

   [1]  USA Standard Code for Information Interchange, USASI X3.4-1968.

   [2]  Postel, J., "User Datagram  Protocol," RFC 768, USC/Information
        Sciences Institute, 28 August 1980.

   [3]  Postel, J., "Telnet Protocol Specification," RFC 764,
        USC/Information Sciences Institute, June, 1980.

   [4]  Braden, R., Editor, "Requirements for Internet Hosts --
        Application and Support", RFC 1123, USC/Information Sciences
        Institute, October 1989.