?? 00000015.htm
字號:
<?xml version="1.0" encoding="gb2312"?><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=gb2312"/><title>TFTP turbolinux </title></head><body><center><h1>BBS 水木清華站∶精華區</h1></center><a name="top"></a>發信人: hellow (收復臺灣是我心), 信區: Embedded <br />標 題: TFTP <br />發信站: BBS 水木清華站 (Sun Nov 5 09:30:15 2000) <br /> <br /> <br />Network Working Group K. Sollins <br />Request For Comments: 1350 MIT <br />STD: 33 July 1992 <br />Obsoletes: RFC 783 <br /> THE TFTP PROTOCOL (REVISION 2) <br />Status of this Memo <br /> This RFC specifies an IAB standards track protocol for the Internet <br /> community, and requests discussion and suggestions for improvements. <br /> Please refer to the current edition of the "IAB Official Protocol <br /> Standards" for the standardization state and status of this protocol. <br /> Distribution of this memo is unlimited. <br />Summary <br /> TFTP is a very simple protocol used to transfer files. It is from <br /> this that its name comes, Trivial File Transfer Protocol or TFTP. <br /> Each nonterminal packet is acknowledged separately. This document <br /> describes the protocol and its types of packets. The document also <br /> explains the reasons behind some of the design decisions. <br />Acknowlegements <br /> The protocol was originally designed by Noel Chiappa, and was <br /> redesigned by him, Bob Baldwin and Dave Clark, with comments from <br /> Steve Szymanski. The current revision of the document includes <br /> modifications stemming from discussions with and suggestions from <br /> Larry Allen, Noel Chiappa, Dave Clark, Geoff Cooper, Mike Greenwald, <br /> Liza Martin, David Reed, Craig Milo Rogers (of USC-ISI), Kathy <br /> Yellick, and the author. The acknowledgement and retransmission <br /> scheme was inspired by TCP, and the error mechanism was suggested by <br /> PARC's EFTP abort message. <br /> The May, 1992 revision to fix the "Sorcerer's Apprentice" protocol <br /> bug [4] and other minor document problems was done by Noel Chiappa. <br /> This research was supported by the Advanced Research Projects Agency <br /> of the Department of Defense and was monitored by the Office of Naval <br /> Research under contract number N00014-75-C-0661. <br />1. Purpose <br /> TFTP is a simple protocol to transfer files, and therefore was named <br /> the Trivial File Transfer Protocol or TFTP. It has been implemented <br /> on top of the Internet User Datagram protocol (UDP or Datagram) [2] <br />Sollins [Page 1] <br /> <br />RFC 1350 TFTP Revision 2 July 1992 <br /> so it may be used to move files between machines on different <br /> networks implementing UDP. (This should not exclude the possibility <br /> of implementing TFTP on top of other datagram protocols.) It is <br /> designed to be small and easy to implement. Therefore, it lacks most <br /> of the features of a regular FTP. The only thing it can do is read <br /> and write files (or mail) from/to a remote server. It cannot list <br /> directories, and currently has no provisions for user authentication. <br /> In common with other Internet protocols, it passes 8 bit bytes of <br /> data. <br /> Three modes of transfer are currently supported: netascii (This is <br /> ascii as defined in "USA Standard Code for Information Interchange" <br /> [1] with the modifications specified in "Telnet Protocol <br /> Specification" [3].) Note that it is 8 bit ascii. The term <br /> "netascii" will be used throughout this document to mean this <br /> particular version of ascii.); octet (This replaces the "binary" mode <br /> of previous versions of this document.) raw 8 bit bytes; mail, <br /> netascii characters sent to a user rather than a file. (The mail <br /> mode is obsolete and should not be implemented or used.) Additional <br /> modes can be defined by pairs of cooperating hosts. <br /> Reference [4] (section 4.2) should be consulted for further valuable <br /> directives and suggestions on TFTP. <br />2. Overview of the Protocol <br /> Any transfer begins with a request to read or write a file, which <br /> also serves to request a connection. If the server grants the <br /> request, the connection is opened and the file is sent in fixed <br /> length blocks of 512 bytes. Each data packet contains one block of <br /> data, and must be acknowledged by an acknowledgment packet before the <br /> next packet can be sent. A data packet of less than 512 bytes <br /> signals termination of a transfer. If a packet gets lost in the <br /> network, the intended recipient will timeout and may retransmit his <br /> last packet (which may be data or an acknowledgment), thus causing <br /> the sender of the lost packet to retransmit that lost packet. The <br /> sender has to keep just one packet on hand for retransmission, since <br /> the lock step acknowledgment guarantees that all older packets have <br /> been received. Notice that both machines involved in a transfer are <br />
?? 快捷鍵說明
復制代碼
Ctrl + C
搜索代碼
Ctrl + F
全屏模式
F11
切換主題
Ctrl + Shift + D
顯示快捷鍵
?
增大字號
Ctrl + =
減小字號
Ctrl + -