Browse Prior Art Database

Telnet Echo Option (RFC0857)

IP.com Disclosure Number: IPCOM000003904D
Original Publication Date: 1983-May-01
Included in the Prior Art Database: 2000-Sep-13
Document File: 5 page(s) / 10K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

J. Postel: AUTHOR [+2]

Abstract

This RFC specifies a standard for the ARPA Internet community. Hosts on the ARPA Internet are expected to adopt and implement this standard.

This text was extracted from a ASCII Text document.
This is the abbreviated version, containing approximately 28% of the total text.

Network Working Group J. Postel

Request for Comments: 857 J. Reynolds

ISI

Obsoletes: NIC 15390 May 1983

TELNET ECHO OPTION

This RFC specifies a standard for the ARPA Internet community. Hosts on

the ARPA Internet are expected to adopt and implement this standard.

1. Command Name and Code

ECHO 1

2. Command Meanings

IAC WILL ECHO

The sender of this command REQUESTS to begin, or confirms that it

will now begin, echoing data characters it receives over the

TELNET connection back to the sender of the data characters.

IAC WON'T ECHO

The sender of this command DEMANDS to stop, or refuses to start,

echoing the data characters it receives over the TELNET connection

back to the sender of the data characters.

IAC DO ECHO

The sender of this command REQUESTS that the receiver of this

command begin echoing, or confirms that the receiver of this

command is expected to echo, data characters it receives over the

TELNET connection back to the sender.

IAC DON'T ECHO

The sender of this command DEMANDS the receiver of this command

stop, or not start, echoing data characters it receives over the

TELNET connection.

3. Default

WON'T ECHO

DON'T ECHO

No echoing is done over the TELNET connection.

4. Motivation for the Option

RFC 857 May 1983

The NVT has a printer and a keyboard which are nominally

interconnected so that "echoes" need never traverse the network; that

is to say, the NVT nominally operates in a mode where characters

typed on the keyboard are (by some means) locally turned around and

printed on the printer. In highly interactive situations it is

appropriate for the remote process (command language interpreter,

etc.) to which the characters are being sent to control the way they

are echoed on the printer. In order to support such interactive

situations, it is necessary that there be a TELNET option to allow

the parties at the two ends of the TELNET connection to agree that

characters typed on an NVT keyboard are to be echoed by the party at

the other end of the TELNET connection.

5. Description of the Option

When the echoing option is in effect, the party at the end performing

the echoing is expected to transmit (echo) data characters it

receives back to the sender of the data characters. The option does

not require that the characters echoed be exactly the characters

received (for example, a number of systems echo the ASCII ESC

character with something other than the ESC character). When the

echoing option is not in effect, the receiver of data characters

should not echo them back to the sender; this, of course, does not

prevent the receiver from responding to data chara...