RFC 913 (rfc913) - Page 1 of 15
Simple File Transfer Protocol
Alternative Format: Original Text Document
Network Working Group Mark K. Lottor
Request for Comments: 913 MIT
September 1984
Simple File Transfer Protocol
STATUS OF THIS MEMO
This RFC suggests a proposed protocol for the ARPA-Internet
community, and requests discussion and suggestions for improvements.
Distribution of this memo is unlimited.
INTRODUCTION
SFTP is a simple file transfer protocol. It fills the need of people
wanting a protocol that is more useful than TFTP but easier to
implement (and less powerful) than FTP. SFTP supports user access
control, file transfers, directory listing, directory changing, file
renaming and deleting.
SFTP can be implemented with any reliable 8-bit byte stream oriented
protocol, this document describes its TCP specification. SFTP uses
only one TCP connection; whereas TFTP implements a connection over
UDP, and FTP uses two TCP connections (one using the TELNET
protocol).
THE PROTOCOL
SFTP is used by opening a TCP connection to the remote hosts' SFTP
port (115 decimal). You then send SFTP commands and wait for
replies. SFTP commands sent to the remote server are always 4 ASCII
letters (of any case) followed by a space, the argument(s), and a
. The argument can sometimes be null in which case the command
is just 4 characters followed by . Replies from the server are
always a response character followed immediately by an ASCII message
string terminated by a . A reply can also be just a response
character and a .
: = [] : = USER ! ACCT ! PASS ! TYPE ! LIST ! CDIR
KILL ! NAME ! DONE ! RETR ! STOR
: = [] : = + | - | | !
can contain
Commands that can be sent to the server are listed below. The server
Lottor