Table 282: Common Telnet Options
Option
Number
|
Option
Code
|
Option
Name
|
Description
|
Defining
RFC
|
0
|
TRANSMIT-BINARY
|
Binary Transmission
|
Allows devices to send data in
8-bit binary form instead of 7-bit ASCII.
|
856
|
1
|
ECHO
|
Echo
|
When you press
a key on a terminal, you also expect to see the character you entered
appear on the terminal screen as output; this is called echoing
the input. Echoing is a significant issue in terminal applications because
it can be implemented in a number of different ways. This option allows
devices to negotiate any of a variety of different echo modes.
|
857
|
3
|
SUPPRESS-GO-AHEAD
|
Suppress
Go Ahead
|
Allows devices not operating
in half-duplex mode to no longer need to end transmissions using the
Telnet Go Ahead command.
|
858
|
5
|
STATUS
|
Status
|
Lets a device
request the status of a Telnet option.
|
859
|
6
|
TIMING-MARK
|
Timing Mark
|
Allows devices to negotiate the
insertion of a special timing mark into the data stream, which is used
for synchronization.
|
860
|
10
|
NAOCRD
|
Output
Carriage-Return Disposition
|
Lets the devices
negotiate how carriage returns will be handled.
|
652
|
11
|
NAOHTS
|
Output Horizontal
Tab Stops
|
Allows the devices to determine
what horizontal tab stop positions will be used for output display.
|
653
|
12
|
NAOHTD
|
Output
Horizontal Tab Stop Disposition
|
Allows the
devices to negotiation how horizontal tabs will be handled and by which
end of the connection.
|
654
|
13
|
NAOFFD
|
Output Formfeed
Disposition
|
Allows the devices to negotiation
how form feed characters will be handled.
|
655
|
14
|
NAOVTS
|
Output
Vertical Tabstops
|
Used to determine
what vertical tab stop positions will be used for output display.
|
656
|
15
|
NAOVTD
|
Output Vertical
Tab Disposition
|
Lets devices negotiation the
disposition of vertical tab stops.
|
657
|
16
|
NAOLFD
|
Output
Linefeed Disposition
|
Allows devices
to decide how line feed characters should be handled.
|
658
|
17
|
EXTEND-ASCII
|
Extended
ASCII
|
Lets devices agree to use extended
ASCII for transmissions and negotiate how it will be used.
|
698
|
24
|
TERMINAL-TYPE
|
Terminal
Type
|
Allows the
client and server to negotiate the use of a specific terminal type.
If they agree, this allows the output from the server to be ideally
customized to the needs of the particular terminal the user is working
on.
|
1091
|
31
|
NAWS
|
Negotiate
About Window Size
|
Permits communication of the
size of the terminal window.
|
1073
|
32
|
TERMINAL-SPEED
|
Terminal
Speed
|
Allows devices
to report on the current terminal speed.
|
1079
|
33
|
TOGGLE-FLOW-CONTROL
|
Remote Flow
Control
|
Allows flow control between the
client and the server to be enabled and disabled.
|
1372
|
34
|
LINEMODE
|
Linemode
|
Allows the
client to send data one line at a time instead of one character at a
time. This improves performance by replacing a large number of tiny
TCP transmissions with a smaller number of larger ones.
|
1184
|
37
|
AUTHENTICATION
|
Authentication
|
Lets the client and server negotiate
a method of authentication to secure connections.
|
1416
|