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Toward reliable operation of minicomputer-based terminals on a TIP (RFC0230)

IP.com Disclosure Number: IPCOM000002864D
Original Publication Date: 1971-Sep-24
Included in the Prior Art Database: 2000-Sep-13
Document File: 3 page(s) / 7K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

T. Pyke: AUTHOR

Abstract

The present protocol for communication between a TIP and attached terminals requires character-oriented transmission and provides for no error control. In the design of this protocol, it was apparently assumed that the majority of terminals attached to a TIP would be interactive, be normally used in a character-by-character mode both for transmission to and from the terminal, and normally support a human user who would in effect be in the communication loop. The human user would thus be in a position to detect any significant telecommunication-induced errors both by direct observation of the character stream and, more importantly, by examining the computer output in the context of his ongoing interaction.

This text was extracted from a ASCII Text document.
This is the abbreviated version, containing approximately 44% of the total text.

Network Working Group T. N. Pyke, Jr.

Request for Comments 230 NBS

NIC 7647 24 September 1971

Category: C5

Reference #203

TOWARD RELIABLE OPERATION

OF MINICOMPUTER-BASED TERMINALS ON A TIP

The present protocol for communication between a TIP and

attached terminals requires character-oriented transmission and

provides for no error control. In the design of this protocol, it was

apparently assumed that the majority of terminals attached to a TIP

would be interactive, be normally used in a character-by-character

mode both for transmission to and from the terminal, and normally

support a human user who would in effect be in the communication loop.

The human user would thus be in a position to detect any significant

telecommunication-induced errors both by direct observation of the

character stream and, more importantly, by examining the computer

output in the context of his ongoing interaction.

The effectiveness of this means for error detection and

initiation of corrective measures when necessary is not adequate in

the following cases:

a. For terminal-TIP communication at a medium or

higher data rate (say 1200 bps or higher) it is quite possible

that the human will skim computer output and not be an

effective character-by-character error detector. In

particular, when both user input and computer output

contain numerical data it is possible that significant

undetected errors could occur.

b. For terminals located at a distance from the TIP

and connected either by a private line or the switched

network more errors may be introduced than with a

terminal local to the TIP (see Note 1). When a large

number of user terminals are connected to TIP's through

telecommunications facilities, whether within a single

organization or, even more likely, when users and user

groups not needing the full TIP capability are connected

to a remote TIP, this problem may arise.

c. For terminals containing a substantial amount of logic,

including possibly a minicomputer, a human user is very

likely not in the direct terminal-TIP communications loop.

This case is important, since both alphanumeric and full

graphics terminals containing minis are now becoming

popular.

d. An interesting potential application of the network is to

provide support for minicomputers used for process

control and other laboratory measurement functions. In

providing software support for such minis as well as

acquiring data from them usually there is no human user

in the communication loop.

e. A number of sites already offer a remote job entry

service. Although the present sites assume that the unit

record devices such as card readers and line printers are

files within a multiprogrammed system at another site, it

appears natural that remote batch terminals...