NAT'L INST. OF STAND & TECH R.I.C.

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Computer

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U.S. DEPARTMENT OF

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Technology Administration National Institute of Standards and

Technology

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NIST Special Publication 500-232

Open System Environment (OSE):

Architectural Framework for

Information Infrastructure

Frederick (Fritz) Schuiz

NIST

PUBLICATIONS
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NIST Special Publication 500-232

Open System Environment (OSE):

Architectural Framework for

Information Infrastructure

Frederick (Fritz) Schuiz

Systems and Software Technology Division

Computer Systems Laboratory

National Institute of Standards and Technology

Gaithersburg, MD 20899-0001

U.S. Department of Commerce

Ronald H. Brown, Secretary

Technology Administration

Mary L. Good, Under Secretary for Technology

National Institute of Standards and Technology

Arati Prabhakar. Director
Reports on Computer Systems Technology

The National Institute of Standards and Technology (NIST) has a unique responsibility for computer

systems technology within the Federal government. NIST's Computer Systems Laboratory (CSL) develops standards and guidelines, provides technical assistance, and conducts research for computers and

related telecommunications systems to achieve more effective utilization of Federal information technology resources. CSL's responsibilities include development of technical, management, physical, and administrative standards and guidelines for the cost-effective security and privacy of sensitive unclassified

information processed in Federal computers. CSL assists agencies in developing security plans and in improving computer security awareness training. This Special Publication 500 series reports CSL re- search and guidelines to Federal agencies as well as to organizations in industry, government, and

academia.

National Institute of Standards and Technology Special Publication 500-232

Natl. Inst. Stand. Technol. Spec. Publ. 500-232, 47 pages (Dec. 1995)

CODEN: NSPUE2

U.S. GOVERNMENT PRINTING OFFICE

WASHINGTON: 1995

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402
Foreword and Acknowledgments

This document represents a collaboration among the sponsor agencies for the National Institute of

Standards and Technology (NIST) Distributed Systems Engineering Program. The following agencies and

individuals contributed their time, experience and documents to the development of this document:

- Department of Defense

Assistant Secretary of Defense for C3I - DASD(IM) Mr. Terry Hagle

DISA Center for Architecture Mr. John Mitchell

- Federal Aviation Administration

Office of the Chief Information Officer Mr. Roger Cooley

- Internal Revenue Service

Office of Systems Engineering Mr. John Tucker

- National Aeronautics and Space Administration

Johnson Space Center Mr. David Pruett Goddard Spaceflight Center Ms. Martha Szczur

- National Institute of Standards and Technology (NIST)

Mgr., Distributed Systems Engineering Group Mr. Fritz Schulz

This document draws from the agency experience and planning documents related to the establisliment of

large scale distributed systems which support their agency mission. The information infrastructure is viewed as an integral element of each of these agencies information technology programs.

In addition to the contributions of those above, special thanks to Jim Tumage (DoD DISA Center for Architecture) and David Farley (IRS) who made contributions to the development of this document. The

following NIST persormel contributed or identified source material in the following areas: Barbara Cuthill

(Software Development), Joe Hungate (Distributed Systems Management), Will Frazier (Security) and

Brenda Gray for her editorial skills, as well as for their review of the overall document. This document

also benefited from substantial review and comment from David Jefferson, Bruce Rosen, and Sheila

Frankel of NIST.

Contributions are also drawn from across the OSE community, including business, government, and the consensus process organizations. The OSE concept has evolved and grown over the past seven years as a

collaboration among many organizations and forums. In addition to the agencies above, special thanks

should go to the information technology user and provider organizations which participated in the IEEE

Posix 1003.0 working group (known as "dot zero"), ISO/IEC SC 22 Working Group 15 (the international

forum for Posix), ISO/IEC JTCl Special Group on Functional Standards (responsible for JTCl profiles).

The regional workshops, including the European Workshop for Open Systems (EWOS), the OSE

Implementors Workshop (OIW) for North America, and the Asiatic/Oceana Workshop (AOW), provided

input, feedback, and a crucial connection to those deploying information technology. Finally, thoughtfiil

review and comment were received from the two organizations active in defining the U.S. approach to information infrastructure. The U.S. Government's Information Infrastructure Task Force (IITF) refined

and focused the relationship between a relatively small system serving a single organization, and the larger

infrastructure. The industry-led Information Infrastructure Standards Panel (IISP) sponsored a very usefiil review and "field trial" of the six interfaces defined in the August 1994 version of this paper.

With such a large and diverse community of discourse, a fiill list of contributors would be almost

impossible to create. Any oversight is regretted.

SP 500-232: Open System Environment Architectural Framework Page iii
PREFACE

This architectural framework document is one of a series of reports which together will provide a comprehensive overview of the National Information Infrastructure (Nil) issues from the three different

perspectives identified by the Information Infrastructure Task Force (IITF). The May, 1994, IITF report

"Putting the Information Infrastructure to Work" provides a "top-down" (or apphcations) perspective. A

"bottom up" (or bitways) view is presented in a July, 1994, Draft of "Framework for National Information

Infrastructure Services." This report is presented from the third perspective, a services/interfaces centered

view of the Nil. Each of these reports, by itself, provides a critical view of the Nil services and

architectural framework, but it is only when viewed from all three perspectives that the true complexity and

scale of the Nil challenge emerges.

Significant Changes Since Version 1, August 5, 1994

New versions of the reference documents resulted in updated terminology, especially in section 6,

addressing the profiling process. Discussion and changes proposed by Information Infrastructure Task Force and the Information

Infrastructure Standards Panel are reflected here, in the treatment of the Network-to-Network

Interface (NNI).

"National class" has been changed to "large scale." "Nil" has been changed to "information infrastructure."

Sections 5.4 "Software Development Capabilities," and 5.3 "Distributed System Management

Capabilities" were substantially updated.

Section 6 "The Profiling Process: Standards and Specification Selection" was rewritten with

additional text describing the types of documents available.

New text was inserted into section 7 "Summary and Conclusions."

Page iv SP 500-232; Open System Environment Architectural Framework
Table of Contents Page

1. INTRODUCTION 1

1.1 Scope 1

1.2 Purpose and Audience 1

2. ARCHITECTURAL FRAMEWORK GUIDELINES AND OBJECTIVES 3

2.1 Nil Principles and Objectives 3

2.2 Technical Capabilities 4

2.3 Application Area Issues 4

3. OSE ARCHITECTURAL FRAMEWORK 7

3.1 Approach 7

3.2 Technology Context - Open System Environment Reference Model 8

3.2. 1 OSE Reference Model - Canonical Form 8

3.2.2 OSE Reference Model - Specific Interfaces and Entities 9

3.2.3 OSE Reference Model - Distributed System 15

4. SERVICE DEFINITIONS 17

4.1 Services at the Human/Technology Interface 17

4.2 Services at the Information Storage Interface 18

4.3 Services at the Communications Services Interface 19

4.4 Services at the Application Program Interface 19

4.4.1 Human/Technology Interaction API Services 20

4.4.2 Information Storage API Services 21

4.4.3 Commmrications API Services 21

4.4.4 System API Services 22

4.5 Services at the Network to Network Interface 22

4.6 Services at the Application-to-AppHcation Interface 23

4.6.1 Directory Services 25

4.6.2 Electronic Mail Service 23

4.6.3 Time Synchronization Service 24

4.6.4 Remote Graphic User Interface Service 24

SP 500-232: Open System Envirormient Architectural Framework Page v
4.6.5 Remote Login 24

4.6.6 Authorization Service 24

4.6.7 Authentication Service 24

4.6.8 Non-Repudiation Service 25

4.6.9 Data Integrity Service 25

4.6. 10 Remote File Access Service 25

4.6.11 File Transfer Service 25

4.6.12 Remote Database Access Service 25

4.6. 13 Unstructured Data Discovery 26

5. MULTIPLE INTERFACE CAPABILITIES .27

5.1 Security/Privacy Capabilities 27

5.2 Internationalization Capabilities 28

5.3 Distributed System Management Capabilities 29

5.4 Software Development Capabilities 30

6. THE PROFILING PROCESS: STANDARDS AND SPECIFICATION

SELECTION 33

6.1 Types of Specifications and Selection Precedence 33

6.2 Selection Process 35

6.3 Specification Selection Criteria 35

6.4 Considerations in Selection of Public Specifications 37

7. SUMMARY AND CONCLUSION 39

ANNEX A: Comparison of Information Technology Interfaces Identified in

Nn Related Documents 41

ANNEX B: References 43

Table of Figures Page

Figure 1: Relationship of Infrastructure to Application Domains 6

Figure 2: OSE Reference Model - Canonical Form 9

Figure 3: OSE Entities and Interfaces 10

Figure 4: Application Platform and Information Appliance Entity Relationship 12

Figure 5 : Network-to-Network Interface (NNI) 14

Figure 6: OSE Reference Model - Full Distributed System 15

Page vi SP 500-232: Open System Envirorunent Architectural Framework
1. Introduction

1.1 Scope

This document identifies a set of interfaces, services, and formats which are to be provided to users of an

information infi-astructure, and the methods for accessing these services. These interfaces, services, and

formats describe an Open System Environment (OSE), enabUng the existing and emerging information

infi-astructure for the communications, computing, and entertainment arenas to seamlessly interoperate.

One purpose of this formulation of the services is to provide a foundation for the selection of the information

technology standards necessary to satisfy information infi-astructure related objectives. Only the minimum

set of services which are required to meet information infi-astructure objectives (listed in section 2) is identified within this document. Concepts which must be agreed upon among all system constituencies are

identified, and any concept or issue which can be left to a more localized authority is explicitly out of scope

for this document.

This document provides a context and guidance for standards selection, but does not identify standards for use within an information infi-astructure. The document may, however, refer to standards in order to

illustrate aspects of the services which are important in making selections among the candidate

specifications.

This discussion will provide a basic set of terminology and concepts to support discussion and resolution of

policy issues.

Finally, technical guidance is provided to agencies which intend to use information infi-astructure for

exchange of government information and services within government, and to deliver government information

and services to citizens and organizations outside of government.

1.2 Purpose and Audience

The purpose of this document is to identify a range of information infi-astructure services and provide a

context for standards selection. The issues involved in service and standards formation are closely related to policy issues such as intellectual property considerations and regulation. Information technology and

technology policy evolve in parallel, and affect each other. This document provides a focal point for assessing the policy options as the technology and consumer expectations evolve.

The establishment of any distributed system which spans multiple organizations requires agreement among

those organizations on a few key issues. These agreements are often codified as standards, but can take

other forms, such as convention, registries, or regulation.

This document begins with an identification of the Nil principles and objectives which will guide the

evolution of the infi-astructure, in section 2. This is followed by a set of capabilities that need to be

established to satisfy the information infrastructure principles and objectives. Section 3 identifies a basic context and terminology that allows a clear statement and discussion of the issues. Types of services are

identified, and the relationships among a few key concepts are outlined.

SP 500-232: Open System Environment Architectural Framework Page 1
Sections 4 and 5 identify the information infrastructure services which must be addressed by the broadest

community. Section 4 describes a general set of service requirements by identifying the services needed at several key interfaces. Section 5 addresses system level services; that is, those capabilities which cannot be

isolated to a single interface.

Section 6 identifies a process and selection criteria which can be used to identify and select among candidate

specifications which potentially satisfy the service requirements.

Page 2 SP 500-232: Open System Environment Architectural Framework
2. Architectural Framework Guidelines and Objectives

According to the Information Infrastructure Task Force report. "The National Information Infrastructure: Agenda for Action.""[l ] the information infrastructure will mclude a wide variety of equipment with differing

capabilities and sen,ices mcludmg "cameras, scanners, keyboards, telephones, fax machines, computers,

switches, compact disks, video and audio tape, cable, wire, satellites, optical fiber transmission lines,

microwa\'e nets. s\\itches, televisions, monitors, printers, and much more.'' The services identified in this architectural framework will include ser\ices applicable to all identifiable service providers. The services

will be those necessars' for interoperability' and portability' between these diverse service providers and

service users, with little distinction drawn between service providers and service users.

The architectural framework will ensure that organizations will be able to "integrate and interconnect these

physical components in a technologically neutral manner so that no one industry' will be favored over any

other. "[1] The services architecture will "assist service prcviders and users in the development of quality

elements of information infrastructure including:

The information itself, which may be in the form of video programming, scientific or business

databases, images, sound recordings, library archives, and other media. Vast quantities of that information exist today in gov ernment agencies and even more valuable information is produced

every day in our laboratories, studios, publishing houses, and elsewhere;

Applications and software that allow users to access, manipulate, organize, and digest the

proliferating mass of information that the Nil's facihties will put at their fingertips;

- The network standards and transmission codes that facilitate interconnection and interoperation

between networks, and ensure the privacy of persons and the security of the information carried, as well as the security and rehability of the networks;

The people ~ largely in the private sector ~ who create the information, develop applications and

services, construct the facilities, and tram others to tap its potential. Many of these people will be

vendors, operators, and service providers working for private industry. ''[1]

2.1 Nn Principles and Objectives

The following Nil principles and objectives from "The National Information Infrastructure: Agenda for Action."[l] are relevant to the definition of services for large scale distributed systems:

1 . Promote Private Sector Investment;

2. Extend the "universal service"' concept to ensure that information resources are available to all at affordable prices;

3. Act as catalyst to promote technological innovation and new applications;

4. Promote seamless, interactive, user-driven operation of the Nil;

5 . Ensure information security and reliability;

6. Improve management of the radio frequency spectrum;

7. Protect intellectual property rights;

8. Coordmate with other levels of government and nations;

9. Provide access to government information and improve government procurement.

SP 500-232: Open System Environment Architectural Framework Page 3
2.2 Technical Capabilities

In order to assure technical feasibility and credibility of this guidance, technical capabilities are identified as

objectives. The architectural fi-amework will describe capabilities and services which citizens and industry can use to access a wide variety of information fi-om government agencies, as well as many other sources. The services will be as independent as possible of information content so as to provide general access

capabilities. The following technical capabilities are taken fi-om the IEEE/ISO "Guide to the POSIX Open

Systems Environment. "[2 ] This set of capabilities is in use in a variety of U.S. and International Open

System Environment (OSE) related activities, and provides important support to the satisfaction of the

objectives in section 2. 1:

1 . Application Portability at the Source Code Level;

2. Data Portability;

3. Application Software Interoperability and Application Platform Interoperability;

4. Common Methods for People to Interact with Technology;

5 . Accommodation of Standards

;

6. Accommodation of New Information System Technology;

7. Application Platform Scalability;

8. Distributed System Scalability;

9. Implementation Transparency;

10. Clear Statement of User Requirements.

2.3 Application Area Issues

The following application areas identified in "

Putting the Information Infrastructure to Work."[3 ] in "The

Information Infrastructure: Reaching Society's Goals/74 ] and "R&D for the Nil: Technical Challenges"[5 ] symposium proceedings, (see bibliography. Annex B) and will be used to validate that the services identified are broadly usefiil:

1. Health Care,

2. Education,

3. Manufacturing,

4. Electronic Commerce,

5. Environmental Monitoring and Information Dissemination,

6. Government Information and Services,

7. Libraries,

8. Electric Power Generation and Distribution,

9. -Transportation,

10 Telecommuting,

11 Emergency Management,

12 Arts, Humanities, and Culture,

13 Law Enforcement and Criminal Justice.

While the selection of a small set of application areas is necessary to focus these service definition activities,

it is recognized that there are many other important application areas. A collection of important issues

common to these application areas could be a usefiil approximation of issues relevant to all application

Page 4 SP 500-232: Open System Environment Architectural Framework
areas. The application area issues identified in "

Putting the Information Infrastructure to Work"f3 1 and

"The Information Infrastructure: Reaching Society's Goals"[4] include:

Equity of Access; Each persons ability to participate as a full citizen in our Republic should be enhanced, rather than

lessened by technological change. Therefore, sensory and mobility impaired citizens must be

included in our vision of the Nil. Non-profit and private organizations must also be included in this vision of the Nil, in addition to for-profit organizations.

Demonstration and Pilot Projects: Demonstrations will reduce risk and verify cost^enefit projections, allowing better return on

investment.

Standards and the Standards Process; Clear goals and coordination will enable the voluntary standards system to work to maximum

efficiency in identifying relevant existing standards, and developing any new standards required.

New mechanisms, structures, and processes can improve standards development, resulting in more

timely response to user needs.

Privacy and Communications Security; Users must have some assurance of the identity of their communicating partner, and assurance that

communication is available only to intended parties.

Training and Support; Without adequate provision for ease of use and training for professionals and those they serve via

the Nil, the projected benefits of the infrastructure will not be achieved.

Research and Development; Research should be fimded and structured to support and sustain the current high rate of

innovation and benefit from the NIL

Performance Measurements; Measures of success should be defined to monitor the actual costs and benefits accrued from the

Nil, and to enable more intelligent investment changes along the way.

Technologically Robust Architecture; A specialized infrastructure which accommodates a limited set of capabilities (e.g., more

entertainment on television) would miss opportunities associated with trends toward

decentralization, connectivity across heterogeneous networks, and radically different services.

Diversity of Content; The infrastructure should allow for all types of cultural exchange, in addition to accommodating

the dynamics of commercial exchange.

Safety in our Homes and Protection of our Neighborhoods; The Nil has the potential of improving coordination among community agencies in time of

emergency, and increasing the exchange of information with citizens with concerns regarding the

environment, transportation, and public safety.

SP 500-232: Open System Environment Architectural Framework Page 5
Citizen control over Private Information; Citizen control over the disclosure of private information held outside their direct control is essential to gaining their confidence, and realizing the benefits of the information infi-astructure.

Figure 1 describes the relationship of technology infi-astructure to application areas. The diagram makes the

important point that it is not possible, nor desirable to establish a separate infrastructure for each application

area. Many application areas will share a common infrastructure, represented by the "Services" and

"Bitways" elements in the diagram. The architectural framework described in this document identifies the

infrastructure which is common to many application areas.

Healthcare Education Manufacturing Other

Application Area Application Area Application Area Application Areas

Services

Bitways

Figure 1 : Relationship of Infrastructure to Application Domains.

Page 6 SP 500-232: Open System Environment Architectural Framework
3. OSE Architectural Framework

Today's large scale distributed systems, such as the Internet, are, and v/ill continue to be composed of

various smaller distributed systems bound together by very capable communications and support services. Each of these component distributed systems will be owned and operated by organizations (e.g., hospitals,

schools, businesses, etc.). These systems will interact with each other in the transfer and sharing of data, but

will not be obligated to respond to management directions from other organizations. The combined

distributed system will not be provided, owned, or administered, by a single authority. It could continue to operate as a cooperative venture, with only a few carefully chosen unique authorities, such as domain

registration authority.

The relationship of these systems may be described 2ls federated. This federation is a voluntary, possibly

transient, association between two or more complex systems. Each organization retains the responsibility for managing the system elements within the organization's scope, while allowing interaction with other systems

in a carefully prescribed way. The process of establishing, operating, and evolving national class distributed

systems is identified as Distributed System Engineering.

Current interactions are primarily confined to exchange of electronic mail messages, and in some cases remote session support. The variety of interactions available is rapidly expanding to include increasingly

complex interaction between application programs on different platforms, often without the direct

involvement of people. It is worth noting that even the Nil itself is a component of a federated system due to

its participation in a broader, global level distributed system.

3.1 Approach

The process of establishing large distributed systems which span multiple organizations requires a distinction to be made between an "architectural framework" and an "architecture." An architecturalframework

identifies key interfaces, entities and services, and provides a context for identifying and resolving policy,

management, and strategic technical issues. The entities and interfaces provide a reference model that

identifies the technology and provides a clear scope for specification. The framework constrains

implementation by focusing on interfaces, but does not dictate design or specific technical solutions. An

engineering organization then selects technology which implements the architectural framework, resulting in a specific design which is documented as an architecture .

This document describes an architectural framework for large scale information infrastructures. An overall

architecture is not specified, since the variety of technology incorporated within the information

infrastructure will vary considerably.

The framework may be tailored to address the needs of an organization which intends to depend on an

external information infrastructure as a key component of the organization's own internal information

infrastructure. This "project" perspective will help assure that pragmatic guidance is available to organizations with development projects and procurements always in progress. To this end, a simple set of

terms will be developed to support the remainder of the document.

An important feature of this approach is that a method for capturing and tracking user requirements is integral to the process. This will help assure that technology and standards track user needs.

SP 500-232: Open System Enviromnent Architectural Framework Page 7
3.2 Technology Context - Open System Environment Reference Model

A distributed system is made up of elements of information technology which interact at specific locations.

The following terminology and Open System Environment Reference Model (OSE RM) identifies the aspects

of a distributed system which are relevant to technical policy discussions. These concepts and terminology

are then used to identify the key interfaces where information infrastructure standards are needed.

Many of the initial concepts for the following were taken fi-om the IEEE/ISO "Guide to the POSIX Open

Systems Environment (0SE),"[2] developed during the period 1988 to 1995. NASA and the Department of

Defense contributed the basic approach from infrastructure projects active during the period 1987 through

1989. Their partnership with the POSIX OSE project (P1003.0), helped to validate the concepts, to provide

valuable feedback to their programs, and broaden the concepts so that they could make more extensive use of

commercial technology. Another ISO/IEC project which provided important feedback was ISO/IEC JTCl

Technical Study Group 1 (TSG-1). This group, and their final report[6 ], established OSE (and profiling) as a major methodology within JTC 1 for handling complex problems such as application portability.

3.2.1 OSE Reference Model - Canonical Form

A discrete, identifiable element of technology is identified as an entity . An entity may be made up of

subsidiary entities, and may also be part of a larger entity. This document makes no naming distinction

among entities with respect to where they fit in a hierarchy of such relationships since it is not necessary to support the policy discussion. As an element of technology, an entity is a "thing" and can be characterized in part by the technology used to implement it. For example, a candle and a light bulb are both

implementations of a "light source" entity.

A boundary between two or more entities is an interface, with a location as an attribute. One method of

characterizing a type of interface is to identify the entities which share the boundary. The distinction

between entities and interfaces is an important one, since technical policy issues associated with interfaces

and those associated with entities are quite different. A service is a capability which a service provider entity makes available to a service user entity at the

interface between those entities. Figure 2 illustrates how these three basic elements are graphically

represented, and the relationships among them. This representation is the canonical form ofthe OSE

reference model.

Page 8 SP 500-232: Open System Environment Architectural Framework
O

'E

CO

Interface

A service requirement is a statement of need for a particular service at a specific interface. An

interface specification is a document which

specifies how a particular service is invoked or provided at a specific mterface. Specifications

are selected in response to a set of service

requirements.

When a service requirement is identified for which no specifications are available, a gap in available standards is said to exist. Identification of gaps and filling gaps is a major

challenge to organizations heavily dependent on

distributed systems for their operation.

The reference model described can be used to

identify the full range of information technology

required to implement large scale distributed

systems. However, it identifies only those

features necessary to support policy discussions

and formulation, or where consensus across all constituencies and participants is required. This

minimal approach focuses on interface

specification, and avoids mandating implementation to assure that the information infrastructure formulation

accommodates the needs of the broadest range of application domains and technology solutions.

Note that the implementation of any systems participating in the information infi-astructure may differ fi-om

the reference model presented. The objective is to define a conceptual reference model which allows

widespread design, implementation, and integration communities to establish the necessary conventions and

assumptions needed to fulfill their responsibilities. Partitioning of function for discussion or specification

does not imply any requirement for similar partitioning in a specific design or implementation.

Figure 2: OSE Reference Model - Canonical Form.

3.2.2 OSE Reference Model - Specific Interfaces and Entities

Using the concepts and terminology above, we now identify the specific interfaces involved in satisfying the

objectives identified in section 2. The interfaces and entities identified are based on related projects and

programs from industry, government, and the standards community. The model begins with a broad

formulation (based on the "Guide to the POSIX Open System Environment"), and then adds further features

from other contributions which address additional areas of interest. The discussion below is a distillation of

the relevant parts of the referenced documents, and is intended to be a management summary'. For a more

detailed discussion, the reader is encourage to review the references listed in the bibliography (Annex B). A

table in Annex A provides an initial identification of the interfaces included in a varietv' of reference models.

Similarities among the interfaces identified in these documents suggest that a convergence on the definition

and role of these interfaces is occurring.

SP 500-232: Open System Environment Architectural Framework Page 9
Figure 3 depicts the specific Open System Environment (OSE) reference model. The model identifies five basic entities (blocks) and four types of interfaces (thick lines). Services are depicted as arrows crossing

each interface. It is the characterization of these services that is the subject of section 4.

Application Software

ADDlication Proaram

Interface (API)

r

Application

Platform

Human/Technology

Interface (HTI)

Information Storage

Interface (ISI) Communication

Service Interface (CSI)

^^^^ People ^^^^^

External Data Storage

Media

Communications

Provider

Figure 3: OSE Entities and Interfaces.

The interfaces will be described, with discussion of the entities included as needed.

An Application Program Interface (API) is the interface between an application software entity and an

application platform, which is the immediate provider of all services necessary for execution of the

application software entity.

Several types of specification are required and available at this interface. In general, any specification

used by a programmer to generate application source code is an API specification. More recently, nonsource code specifications such as language independent API specifications, and binary distribution

formats have become available, to address the need for a non-development portability capability.

Justification for Inclusion: Specification at the API enables:

Page 10 SP 500-232: Open System Environment Architectural Framework
- application portability, supporting the user's need to manage investment in source code;

- vendor independent platform procurement, supporting equitable access to market for all suppliers;

- separate procurement of application platform and application software addressing legal, technical,

economic, and regulatory issues;

- statement of API related intellectual property rights policy;

- application interoperability, which requires consensus on communications API specifications.

A Human/Technology Interface (HTI) is the interface across which people interact with information

technology. The service provided is access to the information infrastructure, and to other people.

The types of specifications at this interface include human factors based descriptions of the events and

capabilities available to a person interacting with information technology.

Justification for Inclusion: Specification at the HTI enables:

reduced training cost, where common methods for invocation of identical or similar functions can be

established;

equal access for all citizens; users to choose among (or change) service providers, but still allows providers to differentiate their

services and products;

competitiveness, since ownership of fundamental HTI methods can provide advantage to one

competitor.

An Information Storage Interface (ISI) is the interface across which information technology interacts with

external storage media. The service provided is persistent storage of data, where the physical storage media

is often removable.

The types of specifications at this interface include physical media and media independent data format

specifications. The major policy issue is with media independent formats, but media is an important

issue for government IT procurement and delivery of service to the citizen.

Justification for Inclusion: Specification at the ISI enables:

migration from old technology media to new media, which is a steady state condition;

available and affordable government information, which may require media distribution;

the delivery and exchange of information, whether by network or by delivery of media, through

consistent data format specifications;

competitiveness, since ownership of basic storage methods can provide advantage to one competitor.

A Communications Service Interface (CSI) is the interface where an application platform accesses external

entities which provide data transport services. The service provided is data transport among application

platforms.

The types of specifications at this interface include those where protocol states, state transitions, data

syntax, and data format are specified for interoperability among application platforms.

Justification for Inclusion: Specification at the CSI enables:

- regulation necessary to provide assurance of service;

SP 500-232: Open System Environment Architectural Framework Page 1

1
- a necessary and fundamental consensus across a very large and diverse population of platform and

communications service providers;

- competitiveness, since ownership of basic communications methods can provide advantage to one

competitor.

The Application Software entity is software that is specific to an application, and is commonly referred to as an application program. For an organization developing application software, it may be represented by a human readable source code listing. For an organization buying application software, an application

software entity may be represented by an executable file. Many organizations both develop and purchase

application software. In either case, there may be data associated with the application program. If so, the

data is considered part of the application software entity. An application software entity is the basic imit of

procurement, development, and operation for an organization which uses software. A particular application

may be characterized by the set of services it requires from the technology in order to execute, i.e., to perform its intended function.

The Application Platform entity is a set of resources, including hardware and software, that implement the

services provided at the platform's interfaces. In particular, it directly provides all of the services to application software executing on that platform.

Application Software and Application Platform are often combined into one entity, referred to as an Information Appliance (lA). This term is used where the presence of configurable and/or separately

procurable software is not visible to the user of a particular component information technology. Examples of

information technology which are currently considered lAs include telephones, set-top cable TV boxes.

Video Cassette Recorders, television sets, fax machines, AM/FM radios, scanners, keyboards, computers of

all kinds, computer monitors, printers, communications switches, routers, gateways, and cameras (film and

video tape). Application platforms may be considered generalized information appliances. The relationship

between Application Platform and Information Appliance entities is shown in Figure 4.

Figure 4: Application Platform and Information Appliance Entity Relationship.

1;

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I
The External Data Storage Media entity is a physical object which can be used to store and play back data

from an application platform or information appliance. Examples of external storage media include floppy

disks, audio and video cassette tape, and CD-ROMs.

People are, of course, one of the most important elements of any distributed system, as they usually

represent the beneficiary of services offered by the system. People are represented as entities to assure that HTI methods and services are robust enough to support users needs. In some cases, people may also provide

services directly via the Nil in a manner similar to the way directory services operators provide services over

the phone system.

The Communications Infrastructure entity is defined from the users perspective, where universal

cormectivity is provided to the fiill set of information appliances and people, nationally (and internationally). In reality the "Communications Infrastructure" is composed of a diverse set of alternative Communication

Networks (CNs) , each associated with a single provider organization. Today, each of those CNs provide a

variety of communication services to a specific (less than universal) group of users, using a variety of

technologies. Examples of CNs include the long distance, regional, wireless, and local telephone switching

systems, satellite systems, cable and radio frequency TV broadcast systems, and LANAVAN service

providers. The communications media used could be cable, optical fiber, microwave (or any part of the

spectrum).

Each of the technologies has a different set of advantages and disadvantages, leading to their use in different

situations. We should expect the diversity in Communications Infrastructure technologies, markets, and

organizations to continue, but the policy objective of "universal cormectivity" for some set of services leads

to the need for interchange among Communication Network providers for that set of services. A Network-to-Network Interface (NNI) is a type of interface where two or more (possibly dissimilar)

conmiunication networks exchange cormectivity services, as shown in Figure 5. The service provided is communication cormectivity to and from the population of information appliances and people directly

accessible by other communication networks and their providers. The direct access population for a communication network and the associated provider is that set of appliances and people who can communicate among themselves without using any other service network provider. Both the Computer

Systems Policy Project (CSPP) "Perspectives on the National Information Infrastructure: Ensuring

Interoperability"[7 ] and the Cross Industry Working Group (XIWT), "An Architectural Framework for the

National Information Infrastructure"[8 ] provide industry perspectives of this key interface.

The types of specifications at this interface include those where protocol states, state transitions, data

syntax, and data format are specified for interoperability among providers of basic data transport

services.

Justification for Inclusion: Specification at the NNI enables:

- universal access to all application services for the user, ensuring competition;

- universal access to the market for the application service provider, ensuring equity;

- competitiveness in the communications services market, allows user to choose among competing

communications service providers.

SP 500-232; Open System Environment Architectural Framework Page 13
Information

Appliance

Communications

Service Interface

^Communication Netwo

Communications Infrastructure

Application Software

Application Platform

^Communication Network

Communications

Service Interface

Network-to-Netvuork Internee

Figure 5: Network-to-Network Interface (NNI).

An Application-to-Application Interface (AAI) is a type of interface where an application software entity accesses services provided by other apphcation entities. The service provided varies with the appUcation

accessed.

The types of specifications at this interface include specification of a basic data transport paradigm, a set of messages including syntax and semantics, specifications of allowed message sequence, and

conventions for handling a variety of situations which may arise.

Justification for Inclusion; Specification at the AAI enables:

conjpetitiveness, since ownership of basic AAI methods can provide advantage to one competitor;

universal access to the market for the application service providers, ensuring equity;

universal access to all application services for the user, ensuring competition among service

providers;

Since many of the services being considered for "universal availability" are provided by application

software entities, standards are required to support service access.

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3.2.3 OSE Reference Model - Distributed System

The full OSE reference model, shown in Figure 6, identifies all of the interfaces and entities described above,

and illustrates the relationships among them. In this abstraction of the full distributed system environment,

multiple application platforms, each serving one or more applications, interact among themselves and with

information appliances by way of common communications mechanism.s. This collection of genenc

interfaces and entities can be used to represent key aspects of large distributed systems such as the internet.

Information

Appliance

People

HTI

External Data Storage

Media

CSI

People

External Data Storage Media

Communication Network I Communication Network

Communications Infrastructure

NNI

Figure 6: OSE Reference Model - Full Distributed System.

SP 500-232: Open System Environment Architectural Framework Page 15
I
4. Service Definitions

This section defines the set of services needed at each of the interfaces defined above, in order to satisfy the

guidelines and objectives identified in section 2. The services specified will be used to drive the selection of

standards and other specifications. Services will be defined at a high level only to establish the scope of

services for which standards are needed; this is not intended to be a complete set in the broadest sense.

4.1 Services at the Human/Technology Interface

Human/Technology Interface (HTI) services allow users to interact with information technology, and to

tailor the HTI to their needs. Depending on the capabilities required by users and applications, services

provided at this interface may include:

Graphical Chent-Server Services: allow a user to control the relationships between graphical user

interface display client and server processes operating within a network;

Display Objects Services: allow a user to control the characteristics of display elements such as

color, shape, size, movement, graphics, context; user preferences; and interactions among display

elements;

Window Management Services: allow a user to control window creation, movement, storage,

retrieval, and removal, and allow relationships among windows to be specified;

Audio Services: allow a user to input, manipulate, and output sound, music, and other forms of

audio. The services also allow the user to control aspects of the service such as volume, bandwidth,

filtering, and storage allocation;

Video Services: allow a user to input, manipulate, and output video. The services also allow the user

to control aspects of the service such as resolution, bandwidth, filtering, and storage allocation.

Synchronization of video and audio services may be required; and

Dialogue Support Services: allow a user to control the defmition of the relationships between what is displayed on the screen (e.g., cursor movements, keyboard data entry, external data entry devices)

and how the display changes depending on the data entered.

User interfaces are a very complex part of system development and maintenance. Within the past few years,

significant advances have been made in user interfaces, both in ease of use and in reducing the development

effort required. Although other technologies can be used, most users think of a user interface in terms of a Graphical User Interface (GUI). A GUI allows a user to specify actions by dragging and dropping or pointing and clicking on an icon that is a pictorial metaphor of the object being acted upon. A GUI may also

support several simultaneous threads of interaction by presenting multiple windows.

The principal components of a window system are a video display interface that contains one or more windows or panels; a pointing device, such as a mouse or touch-screen; and a set of visual objects on the screen that can be directly manipulated by the user through a pointing device or keyboard.

Internationalization services available at the Human/Technology Interface may include providing the user with the:

Ability to select among character sets; Character set identifiers and formats;

Character data presentation;

SP 500-232: Open System Environment Architectural Framework Page 17
Specialized character data input services;

' - Ability to select among cultural conventions;

Ability to select the primary language displayed;

Ability to simultaneously support muhiple language on the same display;

Support of culture specific keyboards; and

Support of culture and language specific messages, i.e., wording or icons that are appropriate to the users cultural conventions and mores. Applications should be independent of any particular natural

language, presenting messages appropriate for the internationalized user environment selected by the

user.

Special formulations of these services may be available for individuals with physical or sensory impairments.

Service availability may be restricted by configurable security or resource allocation constraints.

Authentication services may be invoked one or more times during a usage session in order to limit access to system resources to authorized individuals, and to promote privacy on shared systems.

4.2 Services at the Information Storage Interface

The basic services offered at this interface are persistent storage of data, and data format specification for

interchange. Two types of specifications required at this interface include physical media specifications and

media independent data format specifications. Both are required to establish a capability for data portability

and exchange of large volumes of data via media. Because the continued fast pace of improvement in storage

technology shows no signs of slowing, it is important to consider methods for migration fi"om legacy storage

to new storage technology.

Physical media specifications identify the relevant physical characteristics of distribution media. These

characteristics vary considerably with the media, including:

Magnetic tape and disk;

- CD ROM; and

Smart card and encryption support devices.

Media independent data format specifications identify all information required to read and interpret stored

data. This begins with bit and byte order conventions, and extends to complex data types such as:

Byte, integer, floating point, string, etc.; Compound types, i.e., records, tables; Graphics, animation, image, audio, video, with linkage and synchronization points among the

various media identified; and

Files, documents, etc.

Internationalization data formats defined at the Information Storage Interface include:

Formats for defining character sets and character set identifiers; Collation sequences and character equivalency sets; Formats for defining cultural conventions; and

Natural language message system formats.

Page 18 SP 500-232: Open System Environment Architectural Framework
Service availability may be restricted by configurable security or resource allocation constraints.

Information stored on media may be encrypted to promote privacy on shared storage media. Ownership and

authorization information may be required to support these security capabilities.

4.3 Services at the Communications Services Interface

The services at the application platform to communications infrastructure interface may include one or more

of the following:

packet and/or asynchronous bi-directional data transport with application platform or information

appliance interface addressing;

One, or more inbound audio data streams; One, or more outbound audio data streams; One, or more inbound video data streams; One, or more outbound video data streams; One, or more inbound synchronized audio/video streams; and

One, or more outbound synchronized audio/video streams.

Individual stream bandwidth and aggregate bandwidth may vary, with automatic network accommodation up

to a negotiable maximum.

The National Research Council report, "Realizing the Information Future"[9 ] points out that where

bandwidth is not sufficient to satisfy all requests for services, communications service providers must select a strategy for allocating service. Generally, the provider must choose between imposing delays on users by

adopting a best effort service strategy, or provide for negotiation of service where the traffic source declares

its service requirements so that the network can either reserve and guarantee service or explicitly refuse the

service request. Since this document is limited to definition of services, and will not address implementation,

the above services are to be considered goals (see NRC, pg. 66, for a more detailed discussion).

Note that in implementing these services, voice and video may eventually be supported via the packet data

service, but much of the current installed base of switched phone technology does not support this service.

The National Research Council report proposes the migration to a single unified service at this interface,

where a specified range of qualities of service is supported. The Open Data Network "bearer service" is defined in an abstract way that decouples the service characteristics from any particular technolog>' choice.

The various qualities of service are differentiated by reliability, timeliness, correctness and bandwidth of

delivery.

Service availability may be restricted by configurable security or resource allocation constraints.

Authentication services may be invoked one or more times during a usage session in order to limit access to system resources to authorized individuals, and to promote privacy on shared systems. Encryption services

may be requested during communications operations to promote data confidentiality' as information may

transit shared systems.

4.4 Services at the Application Program Interface

SP 500-232: Open System Environment Architectural Framework Page 19
This section describes those services provided to an apphcation program by the underlying apphcation

platform.

4.4.1 Human/Technology Interaction API Services

These services allow an application program to interact with people at the human/technology interface. The

operations supported may include:

Window manipulations, such as open, close, move, resize; Operation of standard controls such as menus, and dialog boxes;

Invoke execution of command language script;

Manipulation of audio, video and other multi-media operations at the human/technology interface;

Reading input from, and controlling keyboards and pointer devices; and

Querying HTI technology to determine (and set) configuration parameters such as resolution, and

sampling rates.

Specialized Graphics operations and services to an application program include:

Create, delete, and modify features on a display. Features include: ~ Lines and Polylines (i.e., multi-segment lines); ~ Markers; ~ Regions, or fill areas;

^ ~ Display Text and Annotation text; ~ Mesh Surfaces, such as Cell, Triangle strips, and/or Quadrilateral mesh; ~ Surfaces; — Curves; ~ Conies, such as circles, ellipses, parabolas, and hyperbolas; and ~ Models of objects to be displayed.

Image manipulation;

Control and apply color to features; Apply lighting and shading algorithms to collections of graphical objects with multiple light types

and sources; Specify and edit the features and attributes globally and individually;

Transformation of (i.e., scale, translate, rotate, reflect, project, etc.) primitives for construction of more complex objects and for arrangement in the viewing space;

Store and retrieve graphical objects from files; and

Control the timing of the actual display of the display data.

All Graphics operations and services may be required to support both two and three dimensional systems.

Internationalization services available at the Human/Technology Interaction API include providing the

application program with the ability to:

Select among character sets; Control character data presentation;

Provide specialized character data input services;

Page 20 SP 500-232: Open System Environment Architectural Framework
Select among cultural conventions;

Select the primary language displayed;

Simultaneously support multiple language on the same display;

Support of local keyboards; and

Support of natural language message system, i.e., wording or icons that are appropnatc to the user's

cultural conventions and mores. Applications should be independent of any particular natural

language, presenting messages appropriate for the internationalized user environment selected by the

user.

Service availability may be restricted by configurable security or resource allocation constraints.

Authentication services may be invoked one or more times during a usage session in order to limit access to system resources to authorized individuals, and to promote privacy on shared systems.

4.4.2 Information Storage API Services

These services allow an application program to control and manipulate files and information associated with

persistent storage resources. The operations supported include:

File system services such as open, read, write, close; Determine and/or set file attributes such as ownership, privileges, etc.; Hierarchical directory structure operations such as set default directory, list files, etc.; and

Media control operations such as eject media, load, rotate platen, format, etc.

These services also allow an application program to control and manipulate databases and structured data

associated with persistent storage resources. The operations supported include:

Database services such as open, query, add data, update data, delete data, close; Determine and/or set database and data attributes such as ownership, privileges, etc.; Determine and/or set relationships between a database and file systems, etc.; and

Structure data access services.

Service availability may be restricted by configurable security or resource allocation constraints. Encryption

services may be requested during storage or retrieval operations to promote privacy on shared systems.

4.4.3 Communications API Services

These services allow an application program to communicate with other application programs executing on

the same or a remote application platform. A variety of different paradigms are available, each of which is

usefiil for specific situations. The paradigms and operations supported include:

Datagram message service: ~ send message, receive message.

Coimection Oriented Messaging Service: ~ Request coimection to remote application; ~ Send message, receive message via connection; and

SP 500-232: Open System Environment Architectural Framework Page 21
~ Terminate connection to remote application.

In addition to these basic messaging services, conventions and specifications can be used to further refine the

services offered. Two of the more widely used techniques include Remote Procedure Call, and Transaction

Processing. Remote Procedure Call establishes conventions and specifications for semi-automated

generation of source code for simple "request-response" interaction between application programs.

Transaction processing establishes conventions and specifications for conducting complex transactions

among two or more application programs, with a high assurance of data and system integrity. Transaction

processing operations supported include:

Begin transaction;

Commit transaction;

Rollback transaction; and

Failure recovery operation.

Service availability may be restricted by configurable security or resource allocation constraints. Encryption

services may be requested during communications operations to promote data confidentiality, since

information may transit shared systems.

4.4.4 System API Services

These services allow an application program to access resources within the application platform. The

operations supported include:

Core System Services: ~ Application execution and concurrence control (for example for processes and threads); ~ Event, error and exception management; ~ Memory management; ~ Local processor time; ~ Platform internal communications and event synchronization; ~ Determine and/or set processor configuration and environment; and — Access control;

Programming Language Services: ~ Execution sequence (e.g. branching); — ©ata type definition and memory allocation; and ~ Arithmetic operations.

Service availability may be restricted by configurable security or resource allocation constraints.

4.5 Services at the Network to Network Interface

A Network-to-Network hiterface (NNI) is an interface where one or more communication networks exchange

connectivity services. While these services are not directly accessed by the end users, they benefit directly

from the connection to the full population of service providers and people.

Page 22 SP 500-232: Open System Environment Architectural Framework
The services supported at the NNI include:

- data exchange at sufficient rates and volumes to satisfy end to end data transport service

requirements;

management, including participation in network fault detection, identification, isolation and recovery

operations; and

exchange of data required to support resolution of charges for service.

4.6 Services at the AppHcation-to-AppIication Interface

Many of the services provided on distributed systems will be used by application software acting on behalf of

a person. Application software entities exchange services with other applications using an application-toapplication communications paradigm. An Application-to-Application Interface (AAI) specification

specifies how an application sofl^vare entity gains access to the services provided by another application

software entity. The AAI should contain all the information required by an application programmer to either replicate the service or access the service fi"om another application software entity. The application software

entity which provides the service may be called a "server", and that convention will be adopted here.

The services provided by the following specialized servers, and AAI specifications for accessing their services, are needed to implement Nil services. Service availability may be restricted by configurable

security or resource allocation constraints. Authentication services may be invoked one or more times during a usage session in order to limit system access to authorized individuals, and to promote privacy on shared

systems. Encryption services may be requested during communications operations to promote data

confidentiality as information may transit shared systems.

4.6.1 Directory Services

A Directory Service provides network addresses and related information to applications. An application

establishes communication with a directory server and identifies the application with which it will interact. The server returns the network address and related information about the destination application. Addresses

at different levels may be requested and reported, including addresses for the application platform interface,

application platform, or application software entity. The directory service may actually involve a variet\' of

servers, each with varying scope and information content. Interaction with, and among, directory servers is documented in a Directory Server AAI specification.

4.6.2 Electronic Mail Service

An Electronic Mai! Service provides a capability for a person or application software entity- to exchange

messages with other people or application software entities. A person may use any of a varietv- of

specialized applications to compose a message, which may contain any combination of data, text, audio,

video, graphics, and/or images. An application submits a message for electronic delivery by interacting with a mail server. Mail is forwarded to successive servers until the mail reaches the destination, at which point it

is held until requested by the addressee. Interaction with, and among, mail servers is documented in an

Electronic Mail Server AAI specification.

SP 500-232: Open System Environment Architectural Framework Page 23
4.6.3 Time Synchronization Service

A Time Synchronization Service provides a capability for different application platforms on a distributed

system to be synchronized to an accuracy that lies within an arbitrary clock error. Interaction with, and

among, time synchronization servers is documented in a Time Synchronization Server AAI specification.

4.6.4 Remote Graphic User Interface Service

A Remote Graphic User Interface Service provides a capability for a person to interact with one or more

applications which are executing remotely across the network, using graphical user interface techniques. The

Remote Graphic User Interface Service may actually involve a variety of servers, each with a different role and area of concern. Interaction with and among Remote Graphic User Interface servers is documented in a Remote Graphic User Interface Server AAI specification.

4.6.5 Remote Login

A Remote Login Service provides a generalized capability for a person to interact with one or more

applications which are executing remotely across the network, using character-oriented command line interface techniques. The Remote Login Service may actually involve a variety of servers, each with a

different role and area of concern. Interaction with, and among. Remote Login servers is documented in a Remote Login Server AAI specification.

4.6.6 Authorization Service

An Authorization Service provides a capability by which a person or application software entity is associated with a set of privileges and/or resource limitations. An application establishes communication

with an authorization server and identifies the person or application software entity to be checked, and the

privilege invoked or resource requested. The authorization server returns an indication that the authorization

request is valid or invalid. Interaction with, and among, authorization servers is documented in an

Authorization Server AAI specification.

4.6.7 Authentication Service

An Authentication Service provides a level of assurance that a person or application software entity is actually the authorized agent identified. An application establishes communication with an authentication

server and identifies the person or application software entity to be authenticated, along with authentication

information, such as a password or biometric information. The authentication server returns an indication

that the authentication is valid or invalid. Interaction with, and among, a specified set of authentication

servers is documented in an Authentication Server AAI specification.

Page 24 SP 500-232: Open System Environment Architectural Framework
4.6.8 Non-Repudiation Service

A Non-Repudiation Service provides a level of assurance that a transaction carried out by an authorized

person or application software entity will not be repudiated by any interested party. This service is similar to that provided by a Notary Public. Applications operating on behalf of parties wishing to enter into an agreement establish communication with a notary server. Parties with fiduciary responsibility to enter into an agreement are authenticated, and binding commitment to the agreement is registered with the notary

server. The server distributes a copy of the agreement to all parties, including proof of commitment.

Interaction with, and among, notary servers is documented in a Non-Repudiation Server AAI specification.

4.6.9 Data Integrity Service

A Data Integrity Service provides a level of assurance that the content of a set of data remains unchanged

over a period of time. An application operates on the content of a file or other data set according to an

algorithm designed to generate a unique value. The algorithm is not reversible, thereby protecting the

original information fi-om discovery. An application then establishes communication with a data integrity server and reports the integrity value, along with any desired attributes of the data, such as the person or

application soflAvare entity to be associated with the data, or timestamp. Variations allow for integrity

validation and time-stamping without disclosure of content for applications where protection of intellectual property, and establishing origin is important. The server can then provide confirmation of the integrity of

copies, or substantiate claims of origination as needed. Interaction with, and among. Data Integrity servers is documented in a Data Integrity Server AAI specification.

4.6.10 Remote File Access Service

A Remote File Access Service provides a generalized capability for an application to interact with (i.e. read

fi-om, modify, add to) one or more files or file systems which are located remotely across the network. The

service may actually involve a variety of servers, each with a different role and area of concern. Interaction

with, and among. Remote File Access servers is documented in a Remote File Access Server AAI

specification.

4.6.11 File Transfer Service

A File Transfer Service provides a generalized capability for an application to transfer one or more files between application platforms connected by the network. The service may actually involve a variety of

servers, each with a different role and area of concern. Interaction with, and among, file transfer servers is documented in a File Transfer Server AAI specification.

4.6.12 Remote Database Access Service

A Remote Database Access Service provides a generalized capability for a person or application to query

or update one or more databases which are located remotely across the network. The service may actually

involve a variety of servers, each with a different role and area of concern. For example, one or more of the

SP 500-232: Open System Environment Architectural Framework Page 25
databases may consist of metadata describing the content of other databases. Interaction with, and among.

Remote Database Access servers is documented in an Remote Database Access Server AAI specification.

4.6.13 Unstructured Data Discovery

An Unstructured Data Discovery Service provides a generaUzed capabihty for a person or apphcation to browse and search through a variety of unstructured data which may be available locally or fi'om other

systems on the network. Minimum restrictions on the format, amount, or structure may be placed on the

data accessed. Services should provide support for:

Hypertext support that includes network-transparent links, multiple fonts, inline graphics, and

hypergraphic links; Intra-document and infobase searching;

Translation of flat data formats to hypertext formats;

Security, including limiting access by site or user; Digital signing of docimients; and

Encryption of documents for transmission.

The service may actually involve a variety of servers, each with a different role and area of concern.

Interaction with, and among. Unstructured Data Discovery servers is specified in an Unstructured Data

Discovery Server AAI specification.

Page 26 SP 500-232; Open System Environment Architectural Framework
5. Multiple Interface Capabilities

Organizations have many requirements which do not fall neatly on a single interface, but require the

coordinated specification and use of a variety of services at several interfaces. These requirements arc for complex capabilities which are often difficult to define with precision, but are fundamental to successftil application of information technology in the real world.

For example, an organization will need to establish a capability for protecting key systems fi-om damage,

whether accidentally or intentionally inflicted. Part of satisfying the need for this very complex capability

involves providing specific security related services at specific interfaces. For each of the sub-sections

described below, one or more combinations of services in section 4 may be required to provide the capability

described.

5.1 Security/Privacy Capabilities

Security services/capabilities are necessary to protect sensitive information in the information system. The

appropriate level of protection is determined based upon the value of the information to the mission area end

users and the perception of threats to that information. Information system security services are depicted as cross-area services since the mechanisms implemented to provide them may be part of multiple platform

service areas.

The following are security services that fall into this category:

Authentication Service confirms the identities of requesters for use of information system resources. In addition, authentication can apply to providers of data. The authentication service may occur at the initiation of a session or during a session.

Access Control Service prevents the unauthorized use of information system resources. This service

also prevents the use of a resource in an unauthorized way. This service may be applied to various

aspects of access to a resource (e.g., access to communication to the resource, the reading, writing, or deletion of an information or data resource, the execution of a processing resource) or to all accesses to a resource.

Data Integrity Service ensures that data is not altered or destroyed in an unauthorized manner. This

applies to data in permanent data stores and to data in communications messages.

Data Confidentiality Service ensures that data is not made available or disclosed to unauthorized

individuals or computer processes. This service will be applied to devices that permit human

interaction with the information system. In addition, this service will ensure that observation of

usage patterns of communications resources will not be possible.

Non-Repudiation Service ensures that entities engaging in an information exchange cannot deny

being involved in the exchange. This service may take one or both of two forms. First, the recipient

of data is provided with proof of origin of the data. This protects against any attempt by the sender

to falsely deny sending the data or its contents. Second, the sender of data is provided with proof of

SP 500-232: Open System Environment Architectural Framework Page 27
delivery of data. This protects against any subsequent attempt by the recipient to falsely deny

receiving the data or its contents.

Availability Service ensures that timely and regular communications services are available. These

services are intended to minimize delay, or non-delivery of data passed on communications networks.

These services include protecting communications networks from accidental or intentional damage,

and ensuring gracefiil degradation in communication service.

5.2 Internationalization Capabilities

An information infrastructure should provide services that are necessary to support users, irrespective of

their particular natural language or cultural conventions. This supports both the need to accommodate

cultural diversity, and the reality of using the information infrastructure as a vehicle for doing business in the

global marketplace. While it is not expected that every application platform would provide support for all possible natural languages and cultural conventions, the specification of the information infrastructure

services and the interfaces should not preclude such support.

Users may require the simultaneous support of multiple natural languages and cultural convention sets. Therefore, the basic information infrastructure internationalization requirement is to provide a set of services

and interfaces that allow the user to defme, select, and change between different culturally related application

operating environments supported by the particular implementation. Specifically, a user should have the

capability to:

Adjust the output messages of specific fiinctions and utilities to support different natural languages,

cultural conventions and character sets;

Select an internationalized user environment that specifies a particular set of data presentation

characteristics, including cultural conventions, character sets and native language;

Concurrently support different applications functioning in different internationalized user

envirormients, supplying different sets of natural languages, cultural conventions and character sets for different users; and

Support different internationalized user environments, and the associated natural languages, cultural conventions and character sets, without requiring changes to the logic of existing application

programs.

The effect of the user selecting a new internationalized user environment, and its associated natural language,

cultural conventions and character set, should be transparent to application programs.

Internationalization services are provided at the Human/Technology Interface, and the Application Program

Interface. Internationalization data formats including character sets, cultural conventions, and natural

language support messages are identified at the ISI.

Page 28 SP 500-232: Open System Environment Architectural Framework
5.3 Distributed System Management Capabilities

Management services are integral to the day-to-day operation of large scale distributed systems. They

provide the mechanisms to monitor and control the operation of individual applications, file systems,

databases, platforms, networks, and user interaction elements of distributed systems.

Activities required for the operations and administration of distributed systems can take on a very broad

scope. This scope can be as simple as a single open system taking management responsibility for one or more dependent systems, or as complex as those in which there is a transient negotiated division of

management activities. The prescribed manner in which these activities occur between systems determine

important aspects of their relationship.

Services required for management of distributed systems are not fiilly defined. Open System Interconnection

(OSI) Network Management and POSIX system administration functions (e.g., user accounts, resource

administration, etc.) need to be integrated to provide a comprehensive set of management and administration

services. Data and database administration, and other capabilities need to be integrated as well. The

required services, based on those identified by the OSE Implementors Workshop[10 ], include the following:

Application Software Management Services, including: ~ State Management (e.g.. Startup and Shutdown); ~ User and Group Identification; ~ Configuration Control; ~ Service Access Control; ~ Usage Management and Cost Allocation (Accounting); ~ Performance Management; ~ Fault Management; ~ Security Management; ~ License Management; and ~ Software Installation and Distribution.

Application Platform Management Services, including: ~ State Management (e.g.. Startup and Shutdovm); ~ User and Group Identification; ~ Configuration Control; ~ Service Access Control; ~ Usage Management and Cost Allocation (Accounting); ~ Performance Management; ~ Fault Management; — Security Management; and ~ Print Management.

Human/Technology Interface (HTI) Management Services, including: ~ State Management (e.g.. Startup and Shutdown); ~ User and Group Identification; ~ Configuration Control; ~ Service Access Control; ~ Usage Management and Cost Allocation (Accounting); — Performance Management;

SP 500-232: Open System Environment Architectural Framework Page 29
-- Fault Management; and ~ Security Management.

Information Management Services [1 1 ] , including: ~ Database Management (including Data Administration); ~ State Management (e.g.. Startup and Shutdown); ~ User and Group Identification; ~ Configuration Control; ~ Service Access Control; ~ Usage Management and Cost Allocation (Accounting); ~ Performance Management; — Fault Management; ~ File System and Content Integrity Checks; and ~ Media Management (e.g. Backup & Restore).

Communication Management Services, including: ~ State Management (e.g.. Startup and Shutdown); ~ User and Group Identification; ~ Configuration Control; ~ Service Access Control; ~ Usage Management and Cost Allocation (Accounting); ~ Performance Management; ~ Fault Management; and ~ Security Management.

5.4 Software Development Capabilities

Development of application software designed to operate as a part of a large scale distributed system will

pose substantial new challenges. Successfiil application of the information infi-astructure to application areas may require new software development technology and techniques to assure market success. In some

sense the information infi^astructure itself may be a key element in reducing costs, with the potential for a market economy for application software which may enable widespread software reuse and distribution. The

capabilities required, based on those developed by the Navy Next Generation Computer Resources Program

(NGCR)[12], include:

Software Requirements Engineering Service - provides the capability to create and manipulate

representations of requirements, including the ability to: ~ capture and represent system requirements allocated to software elements; ~ analyze system requirements allocated to software elements; ~ refine and evolve system requirements allocated to software elements over time.

Software Design Service - provides the capability to create a design of the software components of a

system or subsystem., or modify such a design to conform to a new set of requirements.

Software Generation Service - provides semi-automatic production of software using existing

components or templates.

Page 30 SP 500-232: Open System Environment Architectural Framework
Software Review and Modification Service - Prepare the source code of an application with a

syntax-directed editor. This editor should have features such as the ability to: ~ Find references to variables, routines, data structures, etc.; ~ Check for syntax errors and assist the user in fixing those errors; ~ Attach commentary to the source code that is not part of the source code.

SoflAvare Simulation and Modeling Service - provides the ability to model (or prototype) a software

design before full implementation takes place.

Software Verification Service - provides the formal verification of software against its formal

specifications for the purpose of locating errors.

Software Compilation Service - Prepare the source code for an application, written in various

programming languages, for execution on the application platform. This includes the ability to specify execution options where necessary. (On many systems, this is the traditional compilation

and linking capability.)

- , Software Static Analysis Service - provide for automatic or manually directed static examination of

source code for software components and display of potential errors. This examination should

support coding styles disciplines, including the ability to: ~ Optionally enforce source code style rules; ~ Reformat source code to conform to style rules; ~ Handle multiple sets of stylistic rules.

Software Debugging Service - support the location and repair of software errors in individual

software components by controlled or monitored execution of the code. This support includes the

ability to: ~ run an application under complete control of a debugger, including tracing and the ability to examine program and data state; ~ attach the debugging tool to an application while it is executing or after it has failed; ~ produce a cross-reference listing of variables, routines, data structures, etc.

Software Execution Efficiency Measurement Service - support the measurement of resource and

time consumed in execution of a software component. Measurement should support accumulated

time and resource consumed by multiple components: ~ Routine or major block of code; ~ Individual lines of code.

Software Testing Service - support the testing of software systems, including the ability to: ~ Generate test cases and test harness; ~ Instrument source programs to output results; ~ Test for resource utilization, reliability, path and domain selection; ~ Perform timing analysis; ~ Support regression testing; and ~ Validate test results against expected results.

Software Build Service - support the integration of separately developed software components into a

single system. Automatically generate executable programs from multiple source code modules,

including the ability to:

SP 500-232: Open System Environment Architectural Framework Page 3

1
~ automatically determine which source code has been changed; ~ automatically determine the dependencies between source code modules; ~ generate previous versions of the software.

Software Reverse Engineering - This service provides the capabilities needed to capture design

information from source or object code and produce design documentation such as structure charts

and call graphs.

Software Traceability Service - support the recording of relationships between artifacts (including

software components) of the software development process. Track revisions to these artifacts effectively including the ability to: — check artifacts out for modification; — check artifacts in after modification; ~ determine the status of artifacts under development; ~ query the modification history of artifacts; ~ create complete revision history of all changes to artifacts.

Page 32 SP 500-232: Open System Environment Architectural Framework
6. The Profiling Process: Standards and Specification Selection

Organizations select the technical specifications to be used to satisfy their operational requirements.

Engineering, procurement, and other organizational activities translate these operational requirements into technology requirements using processes that are generally too flexible, and difficult to codify. One result of

these activities, however, is inevitably a set of technical specifications used as a basis for action by all involved parties. This set of specifications is z profile .

For a distributed system or infrastructure, this process is never completed. A standing process is required to maintain and update the set of profiles and specifications in use. Change may have many drivers. Service

requirements change with the mission and structure of the organization. Sources of this organizational

change are legion and well documented, and include competition (win, lose, or draw), leadership change, size (growth or shrinkage), and economics. New technology may trigger review to find new ways to accomplish

tasks, and may be significant enough to affect the formulation of the organizations objectives (e.g.. World

Wide Web impact on group communications).

Whatever the source, a continuous stream of new requirements, technology, specifications and profiles will be considered by an actively evolving organization. This section outlines some of the concepts and criteria important in that specification selection and profiling process.

6.1 Types of Specifications and Selection Precedence

The identification of a complete, consistent suite of standards which addresses information infrastructure

service requirements will, by necessity, draw from many sources. A brief discussion of the various types and

sources is in order, since choices among these types may be required.

The specifications referred to in this discussion describe the technical flinction oftechnology. Besides the

functional specifications referred to here, other specifications are required for pragmatic engineering and/or

procurement. These additional specifications include performance, quality, reliability, etc. and not currently

included in this document.

Standards are a special case, or type, of specification. They are specifications which have been through a

formal ballot in a group open to wide participation, and have a known community of consensus. In the

United States, there are a variety of voluntary standards organizations, each operating according to a wide

variety of procedures, subject to basic ANSI guidelines. These groups produce formal, or de jure standards.

which are considered U.S. national standards .

Other nations produce their national standards via a variety of methods which may vary greatly from the

U.S. approach. U.S. and other national standards may progress to the international level, and undergo ballot. The scope of ballot may be regional (e.g., European, Pacific Rim, or North American) or global (e.g.,

ISO/IEC). A successfully balloted specification in the first case may be identified as a regional standard,

and in the second case is labeled an international standard.

Users observe that increasingly there are specifications which provide needed and useful extensions to

international standards, have broad consensus, and can meet user business needs in advance of the

completion of the foimal standards process. These specifications other than formal standards are necessary,

SP 500-232: Open System Environment Architectural Framework Page 33
and a variety of these can become available by various means. Any specification which has established some

consensus, but has not been formally balloted, is a public specification.

Often, a proprietary specification becomes widely adopted in the marketplace, by presenting a unique or overwhelmingly superior solution to a user need. The specification is often made available by the developer

of the technology, sometimes in the public domain, sometimes on reasonable terms, in order to ensure widespread adoption. The specification may also become available when the intellectual property protection on the specification expires. These specifications which have been widely adopted as a result of marketplace

success, but have not been through a consensus process are labeled as de facto standards, and are an

important type of public specifications.

A variety of consortia or associations may offer users and providers faster and/or more directed opportunities

to establish specifications. They are often oriented toward establishing a capability or technology in an

environment where collaboration is important to share cost or achieve a critical mass (but not unanimous)

consensus in the market. The specifications from these consortia are important and usefiil sources of concept

and specification for users, but must be adopted carefiilly. Consortia are often established for competitive

advantage, implying that there may be a rival source for competing technology or specifications. Selecting one competitor over the other may cause opposition from the losing side. Clear and equitable process is important in this situation. These organizations produce consortia specifications, another important type of

public specifications.

Finally, there are specifications developed within an organization, where opportunity to participate and

influence the specification is limited to those within the organization and invited guests. This may be

appropriate, for instance, where there are truly unique requirements. These specifications are expensive

since the developing organization must bear not only the cost of developing and maintaining the specification,

but of developing compliant technology as well. Even if the technology is bought fi"om an outside provider,

the price will certainly reflect the fiiU cost of development for unique technology. As an unintended side

effect, use of these internal, or private specifications may make it difficult to make use of otherwise suitable

commercially available technology which becomes available. This can effectively lock the organization into a dependency on the technology provider which can be very difficult and costly to reduce. A private

specification protected by intellectual property restrictions which require an agreement prior to use of the

specification, is a proprietary specification . A precedence order is usually established by an organization in adopting specifications, to meet specific

objectives. An organization may set a higher precedence for international standards, to meet international

business objectives. Another organization may set a higher precedence on an application domain

specification, to assure that unique requirements are met. As an example, the precedence order used for

selection within POSIX 1003.0 [2] is as follows, in the order of most to least preferred:

1 . Approved standards maintained by accredited international standards development organizations;

2. Approved standards developed by accredited regional bodies;

3. Approved standards developed by accredited national bodies;

4. Draft standards developed by accredited international bodies;

5. Draft standards developed by accredited regional bodies;

6. Draft standards developed by accredited national bodies;

7. Approved (as opposed to draft) specifications (widely adopted, but not formal standards) developed

or maintained in an open forum; and

8. Specifications developed by a closed forum.

Page 34 SP 500-232: Open System Environment Architectural Framework
Note that the precedence begins with formal standards, which include the first four entries. The

specifications listed in items five through eight are considered public specifications by the criteria in use in IEEE and ISO. The adherence to any precedence is not hard and fast, and should be considered as one more

factor to be balanced in selecting specifications.

6.2 Selection Process

The process of selecting specifications could be structured to emphasize that specifications are selected to

satisfy service requirements. The process may be summarized as follows:

select fi-om the set of international standards which satisfy the service requirements;

where services are not satisfied, continue down the precedence hierarchy, selecting more

specifications and satisfying fiirther service requirements, until all levels of formal standards have

been searched;

begin selecting fi-om available "public specifications" imtil all sources of public specifications have

been evaluated;

where standards are required, but not available fi^om any source, develop a specification. The

specification should be built on existing specifications and agreements where possible, with a minimimi of invention.

6.3 Specification Selection Criteria

While no single set of guidelines is appropriate for all organizations, it is usefiil to collect and review criteria which have been found to be usefiil. The suggested criteria described below are offered as a starting point

for organizations to adapt to their own needs. The following comments on the selection process and

suggested selection criteria are based on those in IEEE 1003.0

"Guide to the POSIX OSE"

[2], OSE

Implementors Workshop procedures [13 ], ISO/IEC "

Principles and Taxonomy for Open System

Environment Profiles. 'TH ] and the NIST Application Portability Profile (APP)[15 ].

While it is clear that objective criteria are best, subjective measures are inevitable since intangible factors are

important. Judgment is required to balance these criteria while selecting among candidate specifications,

since many of the criteria fundamentally conflict.

These criteria can be applied to selection of both standards and public specifications. Where no candidate

specification satisfies a service requirement, the unsatisfied requirements can be used to guide the

modification of an existing specification which is a close fit, or the development of an entirely new

specification.

Note that while the services are defined in section 4 "Service Definitions" with a clear partitioning in mind,

existing specifications usually better reflect the charter oftheir parent organization. This effect (and the

resulting difficulties) is amplified when multiple standards must be used together to create a profile. These

standards were created within disparate organizations and projects, which were in many cases carried out in isolation from the others. As a result, mapping of services to standards is not simple. Flexibility and a

strong measure of pragmatism will be necessary for success. Criteria which could be considered in selection

of standards and specifications include:

SP 500-232: Open System Environment Architectural Framework Page 35
- Service Requirements Addressed: A specification should be selected in response to specific service

requirements. Standards and/or specifications selected may not align with the partitioning of

services as outlined in section 4.

As a general guideline, specifications which address more (or all) of the stated service requirements

should be favored. Also, those specifications which have a more direct or clear relationship to those

requirements should be favored.

Stage of Development: Another factor involved in the selection of standards is "stage of

completion." That is, there is a standards development life cycle process whose effects need to be

taken into account. Most standards follow a sequence fi^om approved development, through draft,

and on to approved standard.

As a general guideline, where choices are to be made among standards, standards which have

progressed fiirther through the process should be favored.

Stability : This factor refers to anticipated change in the standard over time. This change may

expand or contract the technical coverage of the standard.

As a general guideline, the more stable standards are preferred over those subject to change. In some

cases, however, stable standards should not be selected, as in the case of obsolete or un-implemented

standards.

Scope of Consensus : There are differences among standards development bodies with respect to

their scope of consensus. Formal standards development bodies are typically chartered to develop

standards for either international, regional or national communities. Other measures of scope or consensus are relevant as well. These measures of consensus could address consensus within

relevant technical or commercial communities, for example.

As a general guideline, standards with broader scope of consensus are preferred over standards with narrower scope of consensus scope of coverage. This results in a precedence for standards selection

of international, followed by regional, followed by national body developed standards.

Openness : Standards development organizations can differ fi-om one another by virtue of their "openness." All standards bodies exhibit some legitimate barriers to participation. These may, for

example, result from the need to provide equitable sharing of the cost of the forum. They could also

be a side effect of maintaining a balance of constituencies represented in the membership, or limiting some aspects of participation at the international level to accredited delegations. The result is a

varying degree of consensus in the technical content of the standards across development bodies.

As a general guideline, standards developed by accredited standards development organizations (all of which use an open forum) are preferred over those standards developed by bodies using a closed

forum.

Consistency among Selected Specifications : Sets of standards, often called profiles, must be selected

with some care to assure that those selected are consistent among themselves, i.e., do not contradict or conflict, or preclude the use of each other.

Page 36 SP 500-232: Open System Environment Architectural Framework
As a general guideline, specifications which may be used with a broader range of other specifications are preferred over those specifications which limit or preclude the use of other specifications.

Availability for Unencumbered Implementation: Those specifications that may be used without

encumbrance to implement conforming technology tend to achieve widespread use faster than

specifications which have legal or financial constraints on their use. A specification qualifies as unencumbered even if the document itself is a salable item, as long as implementation of the specification carries no licensing fee.

As a general guideline, specifications with fewer constraints on their widespread use and adoption

are preferred over those specifications with more constraints.

Product Availability: Specifications for which no (or very few) compliant products are available do

not meet user's needs. The quality of available products is also a consideration, since this may

affect the rate of adoption of the specifications.

As a general guideline, specifications with more, higher quality compliant products currently in the

marketplace are preferred over those specifications which have fewer.

Maturity: Mature specifications have evolved through experience and use to be clearly defined, well

understood and widely accepted, with a base of technical concept in widespread use.

As a general guideline, more mature specifications are preferred over less mature specifications.

6.4 Considerations in Selection of Public Specifications

The Publicly Available Specifications should neither overlap with nor conflict with an existing formal

standard or formal standard under development. That is, if a formal standard exists or is under development

that provides the same fiinction as the proposed Publicly Available Specifications, then the Publicly

Available Specifications should be avoided, if possible. If a Publicly Available Specifications adds

fimctionality to a standard, then it should be engineered to augment the formal standards in such a way that service requirements addressed by the formal standards are not adversely affected.

Where more than one Publicly Available Specification might serve as the basis for agreements for the same

technical fiinction, a rationale should be developed to record which of the several candidates should be used

and under what circumstances. Users will make the final choice among competing Publicly Available

Specifications in response to their specific requirements.

The criteria listed above apply to the selection of public specifications, as well as standards. Additional

considerations in the selection of public specifications (known as Publicly Available Specifications in the

workshop) are drawn fi^om the OSE Implementors Workshop (OIW) procedures [13], and include:

Common Description: The specification should be described using conventions, including

conformance statements, appropriate for the existing formal standards which the specification

augments.

Stability : The specification will not change except as required to fix technical and editorial errors.

SP 500-232: Open System Environment Architectural Framework Page 37
Completeness : The specification must be sufficiently complete so as to allow useful and predictable

implementation of the complete functionality from scratch.

Proof of Concept: The specification has been demonstrated in at least one actual implementation to meet the user requirement in question.

Reasonable Terms : The specification is available on terms consistent with copyright and patent

guidelines of appropriate national and international standards communities.

Page 38 SP 500-232: Open System Environment Architectural Framework
7. Summary and Conclusion

A basis for definition of key services required to support information infi-astructure activities includes the

definition of an architectural fi-amework. This approach identifies key entities, interfaces among the entities,

and the services required, all in response to a set of objectives.

A set of objectives, entities, interfaces, and services is identified based on work in the Open Systems

Environment community, produced in a variety of forums over the past seven years. There is evidence of

substantial consensus and convergence on the technical concept described, that could be usefiil for fiirther work on architectural fi-ameworks for large-scale distributed systems.

SP 500-232: Open System Environment Architectural Framework Page 39

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Annex B: References

References with an asterisk (*) after the reference number are hsted as architectural framework

documents in the table in Annex A

[1 ] Information Infrastructure Task Force,

''The National Information Infrastructure: Agenda

for Action." 15 September, 1993.

[2 ]* ISO/IEC TR 14252:1995 "Guide to the POSIX Open System Environment (OSE)." 1995.

(Equivalent to IEEE 1003.0, in development since 1988.

[3 ] NIST Special Publication 857,

"

Putting the Information Infrastructure to Work." DOC,

May 1994.

[4 ] NIST Special Publication 868,

"The Information Infrastructure: Reaching Society's

Goals." DOC, September 1994.

[5 ] Information Infrastructure Task Force, "R&D for the Nil: Technical Challenges." Interuniversify Cortmiunications Council Inc., 1994.

[6]* ISO/IEC JTCl N1335. "

Final Report of ISO|IEC JTCl TSG-1 on Standards necessary to Define Interfaces for Application Portability (lAP)," April 1991.

[7 ]* Computer Systems Pohcy Project (CSPP), "Perspectives on the National Information

Infrastructure: Ensuring Interoperability." February 1994

[8 ]* Cross Industry Working Group (XIWT), "An Architectural Framework for the National

Information Infrastructure." Corporation for National Research Initiatives, September

1994

[9 ]* National Research Council (NRC), "

Realizing the Information Future - The Internet and

Beyond." National Academy Press, June 1994 (also referred to as the Open Data Network,

or ODN report.

[10 ] OSE Implementors Workshop, "Requirements for Distributed Systems Management." Distributed Systems Management Working Group, January 1995

[11] ISO/IEC IS 10032: 1995(E),

"Reference Model of Data Management." 1995. Addresses a

scope similar to Information Management Services described here, but significantly

broader.

[12 ] NIST Special Publication 500-213, "Next Generation Computer Resources: Reference

Model for Project Support Environments (Version 2.0)." DOC, November 1993

[13 ] NIST Special Publication 500-224, "OSE Implementors Workshop Stable Document Part

1 -Workshop Policies and Procedures." DOC. 1993

[14] ISO/IEC JTC 1 TR1 0000-3 : 1 995 , "hiformation Technology - Framework Taxonomy of

International Standardized Profiles - Part 3: Principles and Taxonomy for Open System

Environment Profiles"

[15 ] NIST Special Publication 500-210,

"Application Portability Profile: The US Governments Guide to the Open System Environment (Version 2)." DOC, June 93.

[16 ]* Network Management Forum, "Service Providers Integrated Requirements for Information

Technology," Issue 1 (or "SPIRIT"), September 93

SP 500-232: Open System Environment Architectural Framework

i^V& GOVERNMENT PRINTING OFTICE: 1996 - 404-525/47917

Page 43
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ANNOUNCEMENT OF NEW PUBLICATIONS ON

COMPUTER SYSTEMS TECHNOLOGY

Superintendent of Documents

Government Printing Office

Washington, DC 20402

Dear Sir:

Please add my name to the announcement list of new publications to be issued in the series: National Institute of Standards and Technology Special Publication 500-.

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