Comments on Telnet Protocol Changes (RFC0393)
Original Publication Date: 1972-Oct-03
Included in the Prior Art Database: 2000-Sep-13
Internet Society Requests For Comment (RFCs)
Through this RFC, I am registering my objection to two of the three suggestions for changing the TELNET protocol as described in RFC 328 and am adding my suggestion for the interpretation of the TELNET Reverse Break Control Code.
Network Working Group
Request for Comments: 393 Joel M. Winett
NIC 11585 Lincoln Laboratory
Categories: TELNET LL-67
References: RFC 109, 139, 158,318, and 328 3 October 1972
Comments on TELNET Protocol Changes
Through this RFC, I am registering my objection to two of the
three suggestions for changing the TELNET protocol as described in RFC
328 and am adding my suggestion for the interpretation of the TELNET
Reverse Break Control Code.
This code was originally put in the TELNET protocol to give the
virtual terminal the ability to simulate a real terminal which has the
print suppress capability. If the terminals being used at some
installations do not have the ability to disable the printing
mechanism, the TELNET being used can either ignore this code or
attempt to simulate the function using other means (e. g., blacking
out a number of character positions and returning to the first
character position). Every attempt should be made to allow a network
user of a time-sharing system to have the same facilities as a local
user of the time-sharing system. The specification of TELNET protocol
should not limit the function of users if a function cannot be
supported by all users.
The "Hide-your-input" and "Echo" TELNET control codes provide for the
support of two functions available in some time-sharing systems. The
"Hide-your-input" function is really a special case of the "Echo" mode
of operation where the server tells the user that the server will echo
but the server does not. A separate code is used for this func- tion
since some servers may support this function but may not support the
full "Echo" mode of operation.
] This material has not been reviewed for public release and is [
] intended only for use with the ARPA network. It should not be [
] quoted or cited in any publication not related to the ARPA [
] network. [
The "Hide-your-input" and "Echo" modes of operation are disabled with
the "No-echo" control. ASCII control codes could have been chosen for
these functions but it was decided that the NVT ASCII control codes
should only be specified for commonly used functions.
To indicate the number of characters for which the printing should be
suppressed, the "Hide-your-input" TELNET control could be rede- fined
to include a byte following the "Hide-your-input" control to indicate
the number of characters for which the printing should be concealed.
The "No-echo" control would still be sent so that systems with the
print suppress feature would not have to count characters.
2. Data Types
The protocol should allow a server to support users with character
codes other than ASCII, e. g., EBCDIC. The definition of an alter-
nate character code should include the d...