Network Working Group
Request for Comments: 340
Categories: Telnet
References: RFC 328
Tom O'Sullivan
Raytheon Company
9933 Sudbury, Mass.
15 May 1972


   The proposed change to the TELNET protocol calling for one standard
protocol and dropping the idea of minimum implementation seems
reasonable at this time.

I suggest that both Data Types and Hide Your Input be kept for the

following reasons:

Data Types:

The objection stating that switching out of ASCII results in an irreversible change and loss of control can be met by requiring other codes to provide to a return to ASCII. Each other code may have its own return code, however, it may not always be employed. Other codes are important for alphanumeric terminals that have special devices attached. Several potential cases can be cited:

  1. Cal comp plotter attached to a teletype has logic permitting a program to turn the plotter on and off. When operating I believe it uses an 8 bit code which could conflict with Telnet signals.
  1. Numerically controlled machines, either controlled from a user terminal or code prepared by a HOST computer to be punched on the paper tape punch at a teletype way require the use of an arbitrary 8 bit code.
  1. Experiments controlled from alphanumeric terminal or sensor data collected through a cal-comp like connection may require the use of a full 8 bit code.

In these cases a transparent data type with a provision for a return

to ASCII mode seems desirable.

As more and more use of data base systems in the network is considered, the need for and importance of using access keys, passwords, etc. grows. The fact that it is difficult to select the length of input to be hidden is not a persuasive argument. Potential solutions seem to exist, e.g. the protocol could provide for accepting length statements from the user program, data base system, operating system, etc. and in default of this, use a default length representing the server system expected optimum length.

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