NBSIR 75-744

Proposed Implementation for Development

of User-Terminal Protocols for Computer

Network Access

Albrecht J. Neumann

Systems and Software Division

Institute for Computer Sciences and Technology

National Bureau of Standards

Washington, D. C. 20234

July 1975

Final

Sponsored by:

The National Bureau of Standards

and

The National Science Foundation

Office of Science Information Service

Interagency Agreement NSF CA-68

NBSIR 75-744

PROPOSED IMPLEMENTATION FOR DEVELOPMENT

OF USER-TERMINAL PROTOCOLS FOR COMPUTER

NETWORK ACCESS _^

Albrecht J. Neumann

Systems and Software Division

Institute for Computer Sciences and Technology

National Bureau of Standards

Washington, D. C. 20234

July 1975

Final

Sponsored by:

The National Bureau of Standards

and

The National Science Foundation

Office of Science Information Service

Interagency Agreement NSF CA-68

U.S. DEPARTMENT OF COMMERCE, Rogers C.B. Morton, Secretary

NATIONAL BUREAU OF STANDARDS. Ernest Ambler. Acting Director

FOREWORD

This report is the final report to the National Science Foundation,

under Interagency Agreement NSF CA-68, "Infomation Services Protocol."

Under this grant a study was undertaken to provide the basis for possible

standardization for user-terminal protocols. A workshop was held at NBS

during October 197^, at which 35 invited authorities representing library

and infonnation service users, software and service producers, and Federal

agencies supporting major services were represented. Results of this

workshop are reported in an NBS Technical Note entitled; A Basis for

Standardization of User-Terminal Protocols for Conputer Network Access.

The Technical Note deals with the definition of protocols, and some of the

requiranents for message protocols, both to be entered by the user, and

displayed to the user by the system.

The present report puts a proposed standardization effort into

perspective by outlining related standardization efforts underway, by

iTKlicating some of the basic legal /requirements for standardization,

by outlining objectives for a Federal standardization effort, and by

Indicating further research work required. The planned standardization

effort will be sponsored by the National Bureau of Standards.

ACKNOWLEDGMENT

Constructive conments received from D. Fife, M. Keplinger, and

H. White, helped to clarify the material presented, and their assistance

is gratefully acknowledged.

iii
CONTENTS

Page

FOREWORD iii

ABSTRACT 1

1. Present Status of User-Terminal Protocol Standardization . . 1

2. Related Standardization Activities 2

3. Federal Information Processing Standards . . 5

^- Constraints on the Standardization Process 6

5. Proposed Mechanism for Standai'ds Development 8

6. Further Research and Development Required • • • • • • .10

7. Conclusions 10

8. References 12

iv
PROPOSED IMPLEMENTATION FOR DEVELOPMENT OP

USER-TERMINAL PROTOCOLS FOR COMPUTER NETWORK ACCESS

Albrecht J. Neumann

ABSTRACT

This report summarizes activities undertaken at the National

Bureau of Standards in the area of User-Terminal Protocol Standardization with support from the National Science Foundation, during

the latter part of 197^ and early 1975. Also discussed are present

status of related standardization activities in areas of command

languages, terminal keyboards, and terminology. Legal lirplications

of standardization are indicated, and establishment of a Federal Task

Group for Standardization is proposed to work under the Federal

Information Processing Standards Coordinating and Advisory Committee

(FIPSCAC)

Key words: Command languages; computers; man-machine systems;

networks; system commands; user protocols.

1. Present Status of User-Terminal Protocol Standardization

There are many different varieties of user-terminal protocols,

differing from each other in detail of information required from

a user, and in type of information fed back to the user from the

system. These protocols are used with a great number of data bases (1)

and these data bases are nade accessible through many different

services (2). A preliminary study surveyed six systems, a nonrepresentative sample from the standpoint of comprehensive coverage,

but sufficient to provide an initial analysis and definition of the

problem (3). Under NSF sponsorship a workshop was organized by the

National Bureau of Standards (NBS). This workshop provided an opportunity for information exchange and for exploratory discussions of

standardization problems, among the thirty five participants. A strawman "candidate standard" document was reviewed by the participants, and

the results are reported in a separate document, entitled: A Basis

for Standardization of User-Terminal Protocols for Computer Network

Access (4). Some of the conclusions of the workshop are sumonarized in

following paragraphs.

1
1.2 Conclusions of the Workshop

There ms strong consensus that standardization in the area of

user-terminal protocols is needed to save user time and to facilitate

user access to a variety of systems . There also was consensus that

standardization in selected areas is possible, and indeed desirable.

As a result of the workshop, the following steps were taken:

a. A revision of the working paper was circulated to participants

with a request for comments. The final version is being published (4).

This version will serve as the starting point for standardization of

user-terminal protocols.

b. Plans are being made to convene a Federal Task Group to identify

Federal needs and requirements and possibly develop standards

c . The National Science Foundation extended the interagency

agreement duration for this work to permit smooth transition to an

NBS sponsored standardization program.

d. The National Bureau of Standards expressed its desire to

continue this work and to furnish technical support and leadership to a

Federal Task Group.

. 2. Related Standardization Activities

Several activities are underway which affect possible protocol

standards. They are centered around work being conducted by the

American National Standards Institute (ANSI) and the projects undertaken under the Federal ADP Standards program. A good sunmary of

these activities appears in reference 5. Work in ANSI is done under

the guidance of ANSI Committee X3, Corrputers and information Processing.

2.1 ANSI Committee X3 Conputers and Information Processing

The scope of this committee encompasses standardization related

to systems, conputers, equipments, devices, languages, communication

characteristics, and physical (non-electric) characteristics of

conputers and data processing devices, equipments and systems, and

media for information processing. The committee is responsible for

planning, review, and approval of all domestic standardization within

its scope and serves, with its subgroups, as technical advisor to

its USA member body of the International Organization for Standardization,

Technical Conmittee 97 j Conputers and Information Processing (ISO/TC 97)

in the area of international standardization. Several key committees

are mentioned in the following paragraphs.

2
2.2 ANSI X3 SPARC: Standards Planning and Requirements Committee

A central group has been established under X3 whi.ch coordinates

all standards planmjig activities. This committee evaluates the needs

for systems standards required to effect the practical and economic

interchange of data, files, softvrare and equipment. It also initiates,

analyzes, and makes reconmendations on nevi standards projects as input

for X3 consideration. The committee audits standards development from

a function-al and economic view as contrasted with a technical viewpoint,

and reviews proposed standards before they are submitted to X3. Final

reconmendations for a new standard development effort must include an

analysis of the economic motivation of the user and imnufacturer, implementation and transition considerations, applicational utility in the

systems environment, an^alysis of costs of conversion and con-formance

and relationshi-ps to existing or underxieveloped standards and technical

feasibility. SPARC accepts input from all qualified organizations,

individuals, and government agencies v;ho can contribute to its work.

A special ad hoc group within SPA-RC has been organi.zed to study

the feasibility of operating systems control languages. Parts of a

user protocol may deal -vvlth operating system comnands, and there should

be close coupling beuveen an^ protocol standardization and this group.

2.3 AITSI X3/SPARC/0CSL (Operating System. Control languages)

This group investigates the need for and the feasibility of a standard computer-operating-system, control language. Thi.s includes

control and status aspects of at least interactive, tiinesh.aring and

batch-processing systans. The committee h.as conducted a survey of

language functions for control and status reporting offered by major

operating and single-lan.guage systems and has docum.ented similarities

and differences. .As of 1971 no agreement had been reached for a proposed standard, the possible desirability of multiple standards and

a proposed plan of standardization. The conmittee work has been doraiant

for some five months, has been recently (Spring 1975) revised and h.as

formulated a nevj work program -.-fnlch will include consideration of

elonentary user functions performed by operating systons, determln.ation

of the feasibility of a universal command language, and determination

of the economic inpact of such a command language. While the work of

this group covers an area very close to th.at being investigated by the

CODASYL conmittee on OSCL (see 2 . 4 ), approaches differ markedly. The

SPARC/OSCL group is primarily concerned with establishm.ent of feasibility

and functional "top-down" definition of such a language. The CODASYL

effort has defined a number of elemental language functions based on a variety of existing lan.guages and is planning to iTOrk towards grouping

of these functions and towards establishing a "bottan-up" language design

procedure. Thus, both efforts hopefully will merge and augment each, other.

Close liaison is maintained between both groups with that objective in mind.

3
2.4 CODASYVOSCLTG: Conference on Data Systems Languages/Operating

Systems Command Language Task Group '

The CODASYL effort is subdivided into several standing committees:

the executive, planning, systems, programming languages, and data

description language committees. The executive committee, limited to

15 members, is responsible for the overall management of the standing

comi'nittees . Several Task Groups report to the appropriate standing

committees. The Systems Committee sponsors a Task Group on operating

systems command languages.

This group was established with the following objectives:

1. Investigate functional requirements for communication

betv;een the user, the functional programs and the

hardware. In present day systems all such communication

is normally channeled through the Operating System and

the form of communication is known as the Operating System

Control (or command) language.

2. To determine the functions necessary to define a standard OSCL interface and what problems such a

standard interface implies in the building of an operating system.

This group has been meeting since February 1973 and its members represent

hardware manufacturers, users and academicians.

Close liaison needs to be maintained by user protocol standardizers

with both efforts.

Another related effort designated Committee X3K5 deals with conceptual

erouiDijie and documentation of terms and definitions.

2.5 ANSI Committee X3K5: Terminology and Glossary

This committee coordinates and advises the other technical committees

of X3 in establishment of definitions required for their proposed standards.

It presently is developing a general dictionary for computers and information

processing and also supports development of an international vocabulary

for computers and information processing.

Both character codes and data elements play an important role in

user-terminal protocols and strong efforts are underway in these areas

in Committees X3L2 and X3L8.

2.6 ANSI Committee X3L2: Character Codes

Its scope covers standardization of coded character sets, including

code representations, recording formats and format indicators, and those

characteristics of input/output equipment required to interchange media

between systems and equipment. Study projects underway wtiich may inpact

4
or my be inpacted by user protocol standardization are control codes

for 8 bit sets, mainten^ce of the .'^CII code (X 3.4-1968), and 8 bit code and

code extension procedures.

2.7 ANSI Comnittee X3L8: Representations of Data Elements

The mission of th_is comnittee is to develop standards for describing

the representations of data elements involved in data interchange and for

representing data elements of common interest, such as the elements concerned vrith representation-S of times, locations, individuals, organizations

and materials. The program for proposed standards includes time, time zone and date representations, organization identifiers, representations for

political subdivlsior-S , mailing addresses, and point locations.

Another grouping of standardization tasks is related t:o office machine

standardization

2.8 ANSI Committee X4: Office Flachines

One of the main conponents of a terminal is the keyboard. Standardization of keyboards traditionally falls under the heading of office

machjLnes . Technical Committee X4A9 is concerned vjith keyboard standardization. Present standards for the ASCII keyboard (X7 and Xl4) are under

revision at this time (April 1975). User protocols are heavily influenced

by certain control characters available on present standard codes and also

by the absence of codes required from a standpoint of ease of use and

sinplicity. New user protocols may well require addition of new codes for

certain often used functions such as the system and user signals, help command,

etc. User protocol standardization must build on existing keyboard standards,

but should at the same time inject new requirements into this effort.

2.9 Relevant International Standards

International standards h^ve been and are being developed under the

auspices of the International OrganJ-zation for Standardization (ISO)

Several existing standards might affect implementation of user protocols,

in the areas of data elements for calendar representation (8), (9) and

time of day representation (10)

3. H'ederal information Processing Standards

The Federal Govemm.ent and especially the National Bureau of Standards,

U.S. Departanent of Commerce, play a leadership role in standards development.

Under the ADP Standards Program authorized by Public Law 89-306 (the Brooks

Act):

The Secretary of Comnerce is authorized . . . (2) to

make appropriate recorrmendations to the President relating

to the establishment cf uniforro Federal Automated Data

Processing Standards.

5
Subsequent directives relevant to this program are Executive

Order 11717, and Part 6 of Title 15 of the Code of Federal Regulations.

Under the Executive Order the Secretary of Commerce assumed responsibility

for all functions relating to establishment of Government-wide standards

for automatic data processing, previously performed by the Office of , Management and Budget, Including the function of approving Standards on behalf of the President. Under Part 6 Title 15 of the CFR, the National

Bureau of Standards assumes a leadership role in the management of

activities within the Federal Government relating to the development,

irrplementation, and maintenance of data standards. (7)

It is recognized that information processing standards are being

developed nationally under the auspices of the American National

Standards Institute (ANSI) and internationally under the auspices of

the International Organization for Standards (ISO) . It is inportant

that Federal Information Systems be compatible not only with each other

but with those of State and Local governments, the private sector of the

economy and those of other nations. Accordingly, standards developed to

meet Federal Requironents should to the extent practicable be consistent with

corresponding ANSI and ISO Standards.

In order that Federal interests are adequately reflected in such

standards, NBS in its standards nanagement role is responsible for

assuring Federal participation in. their development^ Such participation

is also required for considering them as Federal standards 'in those

cases where they meet the requirements of the Federal Government or

for initiating independent development actions in cases where ANSI and

ISO efforts do not exist, are too slew, or are leading to results which

will not satisfy the Government's needs.

Federal Information Processing Standardization efforts are undertaken

by task groups sponsored by the Federal Information Processing Standards

Coordinating and Advisory Committee (FIPSCAC). These groups operate under

procedures established by the parent committee. Groups of interest are . FIPS Task Group 2, Data Terminals and Data Interchange System Requirements;

I^sk Group 3 J Character Subsets, Sign Conventions, and Packing Techniques;

Task Group 5, Federal Information Processing Vocabulary; Task Group l4.

Documentation for Information Processing Systems; and Task Group 15, Computer

Systems Security. A proposed standards effort must take into account work

being done by these groups in standardization of terminals, character sets,

terminology, documentation and security.

Constraints on the Standaixiization Process

In the development of standards for user-terminal protocols, the first

consideration must deal with the user need for simple, reliable and effective access protocols. Other important factors to be considered are the

possible impact of standardization on a rapidly emerging ' technology and

possible legal implications, which standardization might have in connection

with stifling of competition. WesseKB) summarizes a recent informal

Federal Trade Coiuidssion opinion given to the American National Standards

Institute (ANSI). In this summary he outlines factors affecting the

standardization process from a lawyer's viewpoint. To quote Wessel (6):

6
"The Federal Trade Cornmission ' s opinion to ANSI is therefore most

enlightening as to the considerations involved, and (as to) what

others must consider even more so. It reads (omitting citations):

"1. Standardization . . . programs must not be used as devices

for fixing prices or otherwise lessening competition.

2. They must not have the effect of boycotting or excluding

competitors

3. They must not have the effect of withholding or controlling

production.

4. Construction or specification standards should not be used

except in exceptional circumstances and never when performance

standards can be developed.

5. Standards must reflect existing technology and allow for

technological innovation.

8. Membership in standards groups must be open to a 1

competitors 5 domestic and foreign

9. Due process including timely hearings and prompt

decisions on claims . . . must be accorded to all interested parties.

10. Unless clearly required by safety considerations, standards

must not restrict the kinds, quantities, sizes, styles or qualities

of products.

11. Proposed standards must be checked by an independent entity

to insure that they are meaningful and relevant.

Ik. In challenges to standards, the burden of proof regarding

reasonableness is upon those who develop and enforce standarxis.

15. All standards must be voluntary."

To quote Wessel again: "... standards . . . can be adopted and can be enforced, if approached properly rather than blindly by the well motivated

but inadequately informed. A careful interdisciplinary effort is essential,

participated in by economists , and representatives of the public in addition

to computer scientists and lawyers. The principle guiding tiiem should be:

1 The following numbered items are selected quotations from the cited

communication

7
STANDARDS: Conputer standards, performance guidelines, . . . should be determined by fairly selected and representative

public organizations so as to improve performance and encourage

maximum reasonable interchange among computer systems and between

economic units without unreasonably impeding technological

development in restraining competition."

These statements refer to voluntary standards only. Such standards

are developed and promulgated by private organizations, under consensus

procedures. Some voluntary standards may however become mandatory

standards, regulations, or codes when they are adopted and implemented

by a regulatory agency, or by agreement or contract between producer and

user. Federal Standards are mandatory for the Federal user community and

its suppliers. Even so, certain basic points outlined above may be worthy

considerations for those concerned with standardization of user-terminal

protocols, including the efforts undertaken by the Federal Govemnent.

5. Proposed Mechanism for Standards Development

The workshop in October 197^ provided a first basis for reaching

consensus that standardization of user-terminal protocols would be

desirable and indeed feasible. Further reflection indicates that standardization efforts, in order to be successful, must be based on needs of

those who will utilize these protocols. It is felt that a government

sponsored standardization group could materially aid in determination of such

requirements using well established coordination mechanisms to obtain this

information. It is proposed that a Federal Task Group be set up under

FIPSCAC sponsorship.

A proposed scope for such a task group is as follows:

Scope : To develop recommendations to the National Bureau

of Standards for user protocol standardization that will improve the

effectiveness of Federal ADP operations and systems that support the

mission requirements of Federal Departments and Agencies.

The following broad areas for tasks provide a basis of departure

for further work and for organization of the task group.

1. To Identify the requirements and needs of Federal departments

and agencies relative to user protocols for conputer networks.

2. To survey, document and evaluate existing industry practices

regarding user protocols

3. To assess the rapidly moving technology and to determine its Impact

on user protocols.

8
4. Based on de-facto practices and Federal government requireii^nts

develop user protocol standards . This would include user entry and exit

procedures for corrputer systems and networks, functional definition and

specification, foraiats and codes, sequencing of functions; hardware and

software considerations, and user procedures.

5. To maintain and revise user protocol standards so that these are responsive to the continuing needs of government users based upon new

applications or technological innovations

6. To serve as the focal point within the Federal Government for

obtaining and expressing the needs of government users to obtain industry,

government and developmental activities involved in the development of

standards for user protocols. This includes, but is not limited to the

American National Standards Institute, and the activities of professional

and trade associations

7. To conduct seminars or synposia, as appropriate, to inform

government users of user protocol standards and their application.

One of the first tasks after establishment of the group would be

to establish a detailed work program. It is envisioned that as a minimum

a one year program would permit obtaining of useful results . The NBS

document: A Basis for Standardization of User Protocols for Corrputer

Network Access (4) would serve as a point of departure.

The work program should contain specific tasks, action items,

responsibility assignments, and milestones.

Operating procedures for the group xvill have to be adopted,

based on existing practices in other groups, and specific needs of

this group

Participants should bring to bear expertise in engineering,

software development, human factors, and sciences dealing with

human communications

A final report by the task group would provide detailed recornnendations

for standardization supported by analysis of economic irrpact of

standardization, consideration of iirplementation and transitional

problems, analysis of conversion costs, relationships to existing standards

or those under development and technical feasibility.

During this study it has become clear that some standardization can be

and should be- undertaken now. At the same time many questions have been

raised which lead to identification of problem areas which need to be

addressed by further research and development work.

9
6 . Further Research and Developnent Requii?ed

While standardization can be initiated based on existing practices

and methods, further work is required to establish a sound scientific

basis for both description and evaluation of user-terminal protocols.

Such protocols imply conplex hardware-software-people interactions,

which need to be described in a uniform descriptive language. Such

language is required for training, teaching, self-instruction, as well

as for maintenance purposes. It is required to communicate "about" userterminal protocols . Such language would include all terms and functions

entered by a user and all messages received by a user at a terminal during

system operation, both under normal conditions and under abnormal, or error conditions . This would include a totally exhaustive taxonomy of

error conditions which would aid him or systems personnel in restoring

the normal operating conditions.

In addition, competing user protocols may have to be evaluated

for purposes of procurement or acquisition. Evaluation criteria need

to be developed dealing with such factors as: ease of learning, ease of

use, ease of reception, readability, structural conplexity, tradeoff

between natural language and symbology and many other similar factors. A

great amount of work has been done in the areas of human factors, human

engineering, industrial psychology, and applied linguistics. This work

needs to be reviewed critically, keeping the user-terminal protocol measurement

problem in mind. Relevant theories need to be identified and experiments

need to be designed and undertaken. This would require considerable interdisciplinary effort. Results would be an evaluative capability which would

provide system criteria for measurement of quality or "goodness" of userterminal protocols

7 . Conclusions

This study has provided an opportunity to make an initial survey of the

user-terminal Interface with a view towards standardization of user-terminal

protocols

There exists a consensus that some standardization in this area is

necessary and indeed is feasible.

At the same time there is strong interaction with existing technology

in form of keyboard and code implementations on one hand, and existing

software and procedures on the other hand. A great variety of existing

keyboard and software inplementatlons must be taken into account. Another

strong factor is developing technology. Automation of data entry needs to

bes considered to explore the user-terminal Interactions required under error

or system malfunction conditions.

10
Caution must be exercised not to inhibit technological progress by

premature standardization.

A Federal Task Group will be established to undertake standardization

in a planned and systematic fashion taking into account technological, legal

and other constraints outlined In this paper and working towards development

of sinple, reliable, and generally applicable user-terminal protocols. In

addition to standai^zation which can begin now in selected areas of userterminal protocols, further research and development work ought to be undertaken in two areas, the descriptive protocol methodology and development of

system evaluation criteria which will lead to a measurement capability and an

ability to quantify protocol quality, in terms of generally applicable factors.

11
8. References

1. D. W. Fife, K. Rankin, E. Fong, J. C. Walker, and B. A. Marron

A Technical Index of Interactive Information Systems , NBS

Technical Note 819, March 197^.

2. B. Marron, E. Fong, and D. Fife, A Mechanized Information

Services Catalog , NBS Technical Note 81^, February 1974

3. A. J. Neumann, User Procedures Standardization for Network

Access, NBS Technical Note 799, October 1973.

4 . A.J. Neumann , A Basis for Standardization of User-Terminal

Protocols , NBS Internal Report , In preparation.

5. National Bureau of Standards, Federal Infornation Processing

Standards Index, PIPS PUB 12-2, December 1974.

6. M. R. Wessel, Setting Standards Can be Illegal

Datamation , January 1975, PP. 145-146.

7. National Bureau of Standards, Objectives and Requirements of

the Federal Information Processing Standards Program , PIPS

PUB 23, February 1973.

8. Writing of Calendar Dates in All-Numeric Form, ISO/R2014, International Organization for Standards.

9. Representation of Ordinal Dates , ISO 2711, International

Organization for Standards

10. Representation of Time of the Day , ISO 3307, International

Organization for Standards.

USCOMM-NBS-DC

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U.S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO. NBS IR 75-71+4

2. Gov't Accession

No.

3. Recipient's Accession No.

4. TITLE AND SUBTITLE

PROPOSED IMPLEMENTATION FOR DEVELOPMENT OF USER-TERMINAL

PROTOCOLS FOR COMPUTER NETWORK ACCESS

5. Publication Date July 1975

6. Performing Organization Code

7. AUTHOR(S)

Albrecht J. NeunBnn

8. Performing Organ. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

10. Project/Task/Work Unit No. 640-0900

11. Contract/Grant No. CA-68

12. Sponsoring Organization Name and Complete Address (Street, City, State, ZIP)

National Science Foundation

Washington, D. C.

13. Type of Report & Period Covered

Final

14. Sponsoring Agency Code

15. SUPPLEMENTARY NOTES

16. ABSTRACT (A 200-word or less factual summary of most si^ificant information. If document includes a significant

bibliography or literature survey, mention it here.) This report sumiarizes activities undertaken at the National Bureau of Standards

in the area of User-Terminal Protocol Standardization with support frxDm the National

Science Foundation, during the latter part of 1974 and 1975. Also discussed are present status of related standardization activities in areas of command languages, terminal keyboards, and terminology. Legal inplications of standardization are

indicated, and establishment of a Federal Task Group for Standardization is proposed

to work under the Federal Infomation Processing Standards Coordinating and Advisorv

Committee (FIPSCAC).

17. KEY WORDS (six to twelve entries; alphabetical order; capitalize only the first letter of the first key word unless a proper name; separated by semicolons)

Command languages; computers; nan-machine systems; networks; system coimands; user protocols.

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