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- U. S. Government Open Systems Interconnection Profile (GOSIP)
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- VERSION 2.0
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- October 1990
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- TABLE OF CONTENTS
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- LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
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- LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
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- FOREWORD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
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- PREFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
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- GLOSSARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
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- 1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
- 1.1 BACKGROUND . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
- 1.2 PURPOSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
- 1.3 EVOLUTION OF THE GOSIP . . . . . . . . . . . . . . . . . . . . . 1
- 1.4 SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
- 1.5 APPLICABILITY . . . . . . . . . . . . . . . . . . . . . . . . . 2
- 1.6 GOSIP VERSION 2 FUNCTIONALITY . . . . . . . . . . . . . . . . . 2
- 1.7 GOSIP Version 1 Errata . . . . . . . . . . . . . . . . . . . . . 3
- 1.8 SOURCES OF PROTOCOL SPECIFICATIONS . . . . . . . . . . . . . . . 3
- 1.8.1 Primary Source . . . . . . . . . . . . . . . . . . . . . . . 3
- 1.8.2 Secondary Sources . . . . . . . . . . . . . . . . . . . . . 3
- 1.8.3 Tertiary Sources . . . . . . . . . . . . . . . . . . . . . . 4
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- 2. TESTING OF GOSIP-COMPLIANT PRODUCTS . . . . . . . . . . . . . . . . . 5
- 2.1 CONFORMANCE TESTING . . . . . . . . . . . . . . . . . . . . . . 5
- 2.2 INTEROPERABILITY TESTING . . . . . . . . . . . . . . . . . . . . 5
- 2.3 PERFORMANCE TESTING . . . . . . . . . . . . . . . . . . . . . . 6
- 2.4 FUNCTIONAL TESTING . . . . . . . . . . . . . . . . . . . . . . . 6
- 2.5 VENDOR ENHANCEMENTS . . . . . . . . . . . . . . . . . . . . . . 6
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- 3. DESCRIPTIONS OF ARCHITECTURE AND PROTOCOLS . . . . . . . . . . . . . 7
- 3.1 ARCHITECTURE DESCRIPTION . . . . . . . . . . . . . . . . . . . . 7
- 3.2 PROTOCOL DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . . 10
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- 4. PROTOCOL SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . 12
- 4.1 USE OF THE LAYERED PROTOCOL SPECIFICATIONS . . . . . . . . . . . 12
- 4.1.1 Protocol Selection . . . . . . . . . . . . . . . . . . . . . 12
- 4.1.2 Service Interface Requirements . . . . . . . . . . . . . . . 12
- 4.1.3 Performance Requirements . . . . . . . . . . . . . . . . . . 13
- 4.2 END SYSTEM SPECIFICATION . . . . . . . . . . . . . . . . . . . . 13
- 4.2.1 Physical Layer . . . . . . . . . . . . . . . . . . . . . . . 13
- 4.2.2 Data Link Layer . . . . . . . . . . . . . . . . . . . . . . 13
- 4.2.3 Network Layer Service . . . . . . . . . . . . . . . . . . . 14
- 4.2.3.1 Connectionless Mode Network Service . . . . . . . . 14
- 4.2.3.2 Connection-Oriented Network Service . . . . . . . . 14
- 4.2.3.3 Network Layer Protocol Identification . . . . . . . 15
- 4.2.3.4 Special Provisions For Integrated Services Digital
- Networks . . . . . . . . . . . . . . . . . . . . . . . 15
- 4.2.4 Transport Layer . . . . . . . . . . . . . . . . . . . . . . 16
- 4.2.4.1 Connection-Oriented Transport Service . . . . . . . 16
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- 4.2.4.2 Connectionless Mode Transport Service . . . . . . . 16
- 4.2.5 Session Layer . . . . . . . . . . . . . . . . . . . . . . . 16
- 4.2.6 Presentation Layer . . . . . . . . . . . . . . . . . . . . . 17
- 4.2.7 Application Layer . . . . . . . . . . . . . . . . . . . . . 17
- 4.2.7.1 Association Control Service Elements . . . . . . . . 17
- 4.2.7.2 File Transfer, Access, and Management Protocol (FTAM) 17
- 4.2.7.3 Message Handling Systems . . . . . . . . . . . . . . 17
- 4.2.7.4 Virtual Terminal (VT) Basic Class . . . . . . . . . 18
- 4.2.8 Exchange Formats . . . . . . . . . . . . . . . . . . . . . . 18
- 4.2.8.1 Office Document Architecture (ODA) . . . . . . . . . 18
- 4.3 INTERMEDIATE SYSTEM SPECIFICATION . . . . . . . . . . . . . . . 19
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- 5. ADDRESSING REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . 20
- 5.1 NETWORK LAYER ADDRESSING AND ROUTING . . . . . . . . . . . . . . 20
- 5.1.1 NSAP Address Administration, Routing Structures and NSAP
- Address Structure . . . . . . . . . . . . . . . . . . . . . . 20
- 5.1.2 NSAP Address Registration Authorities . . . . . . . . . . . 22
- 5.1.2.1 Responsibilities Delegated by NIST . . . . . . . . . 22
- 5.1.3 GOSIP Routing Procedures . . . . . . . . . . . . . . . . . . 23
- 5.2 UPPER LAYERS ADDRESSING . . . . . . . . . . . . . . . . . . . . 23
- 5.2.1 Address Structure . . . . . . . . . . . . . . . . . . . . . 23
- 5.2.2 Address Assignments . . . . . . . . . . . . . . . . . . . . 24
- 5.2.3 Address Registration . . . . . . . . . . . . . . . . . . . . 24
- 5.3 IDENTIFYING APPLICATIONS . . . . . . . . . . . . . . . . . . . . 24
- 5.3.1 FTAM and File Transfer User Interface Identification . . . . 24
- 5.3.2 MHS and Message User Interface Identification . . . . . . . 24
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- 6. SECURITY OPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . 26
- 6.1 REASON FOR DISCARD PARAMETERS . . . . . . . . . . . . . . . . . 26
- 6.2 SECURITY PARAMETER FORMAT . . . . . . . . . . . . . . . . . . . 27
- 6.2.1 Parameter Code . . . . . . . . . . . . . . . . . . . . . . . 27
- 6.2.2 Parameter Length . . . . . . . . . . . . . . . . . . . . . . 27
- 6.2.3 Parameter Value . . . . . . . . . . . . . . . . . . . . . . 27
- 6.2.3.1 Security Format Code . . . . . . . . . . . . . . . . 28
- 6.2.3.2 Basic Portion . . . . . . . . . . . . . . . . . . . 28
- 6.2.3.3 Extended Portion . . . . . . . . . . . . . . . . . . 28
- 6.3 BASIC PORTION OF THE SECURITY OPTION . . . . . . . . . . . . . . 28
- 6.3.1 Basic Type Indicator . . . . . . . . . . . . . . . . . . . . 28
- 6.3.2 Length of Basic Information . . . . . . . . . . . . . . . . 29
- 6.3.3 Basic Information . . . . . . . . . . . . . . . . . . . . . 29
- 6.3.3.1 Classification Level . . . . . . . . . . . . . . . . 29
- 6.3.3.2 Protection Authority Flags . . . . . . . . . . . . . 29
- 6.4 EXTENDED PORTION OF THE SECURITY OPTION . . . . . . . . . . . . 30
- 6.4.1 Extended Type Indicator . . . . . . . . . . . . . . . . . . 31
- 6.4.2 Length of Extended Information . . . . . . . . . . . . . . . 31
- 6.4.3 Extended Information . . . . . . . . . . . . . . . . . . . . 31
- 6.4.3.1 Additional Security Information Format Code . . . . 32
- 6.4.3.2 Length of Additional Security Information . . . . . 32
- 6.4.3.3 Additional Security Information . . . . . . . . . . 32
- 6.5 USAGE GUIDELINES . . . . . . . . . . . . . . . . . . . . . . . . 33
- 6.5.1 Basic Portion of the Security Option . . . . . . . . . . . . 33
- 6.5.2 Extended Portion of the Security Option . . . . . . . . . . 33
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- 6.6 OUT-OF-RANGE PROCEDURE . . . . . . . . . . . . . . . . . . . . . 33
- 6.7 TRUSTED INTERMEDIARY PROCEDURE . . . . . . . . . . . . . . . . . 34
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- REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
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- APPENDICES
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- FOREWORD TO THE APPENDICES . . . . . . . . . . . . . . . . . . . . . . . 41
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- APPENDIX 1. SECURITY . . . . . . . . . . . . . . . . . . . . . . . . . . 42
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- APPENDIX 2. SYSTEM AND ARCHITECTURE . . . . . . . . . . . . . . . . . . 46
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- APPENDIX 3. UPPER LAYERS . . . . . . . . . . . . . . . . . . . . . . . 50
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- APPENDIX 4. EXCHANGE FORMATS . . . . . . . . . . . . . . . . . . . . . . 56
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- APPENDIX 5. LOWER LAYER PROTOCOLS . . . . . . . . . . . . . . . . . . . 59
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- APPENDIX 6. ACRONYMS . . . . . . . . . . . . . . . . . . . . . . . . . . 62
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- LIST OF FIGURES
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- Figure 3.1 GOSIP Version 1 OSI Architecture . . . . . . . . . . . . . . 8
- Figure 3.2 GOSIP Version 2 OSI Architecture . . . . . . . . . . . . . . 9
- Figure 5.1.1 NSAP Address Structure . . . . . . . . . . . . . . . . . . 20
- Figure 5.1.2 The NIST ICD Addressing Domain . . . . . . . . . . . . . . 21
- Figure 5.1.3 GOSIP NSAP Address Structure . . . . . . . . . . . . . . . 21
- Figure 5.2.1 Upper Layers Address Structure . . . . . . . . . . . . . . 24
- Figure A.1 Framework for OSI Security . . . . . . . . . . . . . . . . . 45
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- LIST OF TABLES
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- Table 5.3 Required O/R Name Attributes . . . . . . . . . . . . . . . . . 25
- Table 6.1 Extended Values in the Reason For Discard Parameter . . . . . 26
- Table 6.2 Security Parameter Format . . . . . . . . . . . . . . . . . . 27
- Table 6.3 Format - Parameter Value Field . . . . . . . . . . . . . . . . 27
- Table 6.4 Format - Basic Portion . . . . . . . . . . . . . . . . . . . . 28
- Table 6.5 Format - Basic Information Field . . . . . . . . . . . . . . . 29
- Table 6.6 Classification Levels . . . . . . . . . . . . . . . . . . . . 29
- Table 6.7 Protection Authority Bit Assignments . . . . . . . . . . . . . 30
- Table 6.8 Format - Extended Portion . . . . . . . . . . . . . . . . . . 31
- Table 6.9 Format - Extended Information Field . . . . . . . . . . . . . 32
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- FOREWORD
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- The U.S. Government Open Systems Interconnection (OSI) Advanced Requirements
- Group was established by the National Institute of Standards and Technology
- (NIST) in cooperation with the Information Resource Managers of the Federal
- agencies. The group's purpose is to coordinate the acquisition and operation
- of OSI products by the Federal government. This document specifies the U. S.
- Government OSI profile. A profile is a cross-section of functional
- applications pertaining to a particular environment.
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- It is expected that the Administrator of the General Services Administration
- (GSA) will provide for the implementation of Open Systems Interconnection
- (OSI) according to this profile.
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- The National Institute of Standards and Technology (NIST) will issue this
- profile as a Federal Information Processing Standard (FIPS). This is Version
- 2 of the Government Open Systems Interconnection Profile. It contains an
- updated specification of the OSI protocols that meet government needs.
- Products based on these protocols are or soon will be available from major
- vendors.
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- Organizations contributing to the development of this profile are given below.
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- Department of Agriculture
- Department of Commerce
- Department of Defense
- Department of Energy
- Department of Education
- Department of Health and Human Services
- Department of Housing and Urban Development
- Department of the Interior
- Department of Justice
- Department of Labor
- Department of Transportation
- Department of the Treasury
- Environmental Protection Agency
- General Services Administration
- Library of Congress
- National Aeronautics and Space Administration
- National Communications System
- National Science Foundation
- Office of Management and Budget
- Veterans Administration
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- PREFACE
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- This is a Federal Government procurement profile for open systems computer
- network products. Section 1 contains introductory material, the purpose and
- scope of the profile, and the sources of the protocol specifications contained
- in the profile. Section 2 contains general statements on conformance,
- interoperation and performance of network systems covered by this profile.
- Section 3 contains a brief description of the OSI architecture and protocols
- that apply to this profile. The network protocols are specified in section 4,
- the principal part of this profile. Accompanying each protocol implementation
- reference is a statement of conformance identifying the required functional
- units of that protocol. section 5, Addressing Requirements, is also an
- integral and mandatory part of this profile. Technical Support Personnel to
- Acquisition Authorities must be familiar with the terminology and ideas
- expressed in sections 4 and 5.
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- Section 6 defines security options that, if needed, must be explicitly
- requested in Requests For Proposals.
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- This profile will change with improvements in technology and with the
- evolution of network protocol standards. Appendices specify future work items
- needed to enrich the profile, and thus, improve its utility to the agencies.
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- GLOSSARY
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- The terms defined below are used frequently throughout this profile. They are
- defined here to aid the lay reader. Other terms appearing in sections 4 and 5
- are defined in Federal Standard 1037A and ISO 7498 and must be thoroughly
- understood by the Technical Support Personnel to Acquisition Authorities.
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- Protocol
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- In the Open Systems Interconnection reference model, the communication
- functions are partitioned into seven layers. Each layer, N, provides a
- service to the layer above, N+1, by carrying on a conversation with layer N on
- another processor. The rules and conventions of that N-layer conversation are
- called a protocol.
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- End System
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- An end system (ES) contains the application processes that are the ultimate
- sources and destinations of user oriented message flows. The functions of an
- end system can be distributed among more than one processor/computer.
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- Intermediate System
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- An intermediate system (IS) interconnects two or more subnetworks. For
- example, it might connect a local area network with a wide area network. It
- performs routing and relaying of traffic. A processor can implement the
- functions of both an end system and an intermediate system.
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- A system implementing all seven layers of protocol may provide service
- directly to users (acting as an end system), and it may connect subnetworks
- (acting as an intermediate system). When it performs the functions of an
- intermediate system, only the lower three layers of protocol are exercised.
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- Open System
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- An open system is a system capable of communicating with other open systems by
- virtue of implementing common international standard protocols. End systems
- and intermediate systems are open systems. However, an open system may not be
- accessible by all other open systems. This isolation may be provided by
- physical separation or by technical capabilities based upon computer and
- communications security.
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- Federal Government Terminology
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- The following definitions are informal and generic and are provided for the
- benefit of private sector organizations that review the profile. Agency
- regulations and any contract should be referred to for precise terms and their
- usage. Also, other terms may be used in lieu of these in agency regulations
- and in specific contracts.
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- Acquisition Authority
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- An Acquisition Authority, commonly known as a contracting officer, is an
- individual who, under Federal law and acquisition regulations, has the
- authority to enter into, administer, and/or terminate a government contract.
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- Federal Acquisition Regulation (FAR)
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- The FAR is applicable to Executive departments and agencies of the Federal
- Government in the area of acquisition, leasing, and rental of personal
- property and services. Many departments and agencies have supplementary
- regulations that apply to their acquisitions.
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- Federal Information Resources Management Regulation (FIRMR)
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- The FIRMR is applicable to federal departments and agencies in the areas of
- management, acquisition and use of information resources, including automatic
- data processing and telecommunications equipment and services.
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- Requests For Proposals (RFP)
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- Requests For Proposals are documents issued by the government to request bids
- for products or services.
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- 1. INTRODUCTION
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- 1.1 BACKGROUND
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- Both the government and the private sector recognize the need to develop a set
- of common data communication protocols based on the International Organization
- for Standardization's seven-layer Open Systems Interconnection (OSI) Basic
- Reference Model [ISO 1]. In the past, vendor-specific implementations of data
- communication protocols led to isolated domains of information, very difficult
- and expensive to bridge. Recent advances in communication technology based on
- the OSI model offer alternatives to vendor-specific network solutions. Most
- significantly, advances in open systems allow the interoperation of end
- systems of different manufacture, when required.
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- This Government Open Systems Interconnection Profile (GOSIP) is based on
- agreements reached at the National Institute of Standards and Technology
- (NIST) Workshop for Implementors of Open Systems Interconnection. Each new
- version of GOSIP will reference the latest appropriate version of the Stable
- Implementation Agreements for Open Systems Interconnection Protocols [NIST 1],
- hereafter referred to as the Workshop Agreements. The Workshop Agreements
- record stable implementation agreements of OSI protocols among the
- organizations participating in the NIST Workshop for Implementors of OSI.
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- A new version of the Workshop Agreements is created each year at the December
- OSI Implementors' Workshop meeting. It is the intent of the NIST Workshop
- that new versions of the Workshop Agreements will be backwardly compatible
- with previous versions. New editions of the same version of the Workshop
- Agreements are published at regular intervals during the year. These new
- editions contain errata and clarifications to the original agreements that are
- approved by the Workshop plenary. The latest editions are being distributed
- to all workshop attendees and are available through the National Technical
- Information Service (NTIS). See NIST Reference 1 for ordering information.
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- GOSIP is also consistent with and complementary to industry's Manufacturing
- Automation Protocol (MAP) [MISC 1] and Technical and Office Protocols (TOP)
- [MISC 2] specifications. GOSIP addresses the need of the Federal Government
- to move immediately to multi-vendor interconnectivity without sacrificing
- essential functionality already implemented in critical networking systems.
- All capabilities described herein exist as standard products or are close
- enough to market that they can be proposed by vendors.
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- 1.2 PURPOSE
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- This profile is the standard reference for all federal government agencies to
- use when acquiring and operating ADP systems or services and communication
- systems or services intended to conform to ISO Open Systems Interconnection
- protocols which provide interoperability in a heterogeneous environment.
- 1.3 EVOLUTION OF THE GOSIP
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- The GOSIP FIPS will be updated by issuing new versions at appropriate
- intervals to reflect the progress being made by vendors in providing OSI
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- products with new services useful to Federal agencies. A new version of GOSIP
- will supersede the previous version of the document because it will include
- all of the protocols in the previous version plus additional new protocols.
- Procurement of the new protocols is mandated in Federal procurement requests
- initiated eighteen months after the version of GOSIP containing those
- protocols is promulgated as a FIPS. Every new version of GOSIP will specify
- the architecture and protocols that were included in each of the previous
- versions so that Federal agencies can easily determine the applicable
- compliance date for each protocol.
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- It is a goal that a new version of GOSIP will be upwardly compatible with the
- previous versions. However, changes may be required to correct errors and to
- align with activity in the international standards organizations. Any errata
- required to a previous version of GOSIP will be identified in the new GOSIP
- version. Unless otherwise stated, the mandatory compliance date of the
- previous version of GOSIP also
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- applies to the errata. These errata will not be included without ensuring that
- they have the strong support of the vendors who are providing OSI products so
- that users can be confident that these changes will not inhibit
- interoperability. See section 1.7 for the GOSIP Version 1 errata.
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- 1.4 SCOPE
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- In an increasingly complex world, the need to exchange information has become
- an ever more important factor in conducting business. Federal agencies need
- to share information not only with other Federal agencies, but with state and
- local governments and commercial organizations as well. Until recently,
- computer networking technology has not kept pace with this need to
- communicate. Even now, many Federal agencies have "islands" of computer
- systems built by different vendors, or by the same vendor, that cannot
- interoperate.
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- The GOSIP, in addition to being a Federal mandate, is an alert that the vendor
- community has developed a nonproprietary solution for this requirement to
- exchange information. The solution is the OSI protocols upon which GOSIP is
- based. Version 1 of GOSIP (FIPS 146) provided electronic mail and file
- transfer services using the OSI standards for Message Handling Systems (MHS)
- and File Transfer, Access, and Management (FTAM). Version 1 of GOSIP provided
- interoperability among users on X.25, 802.3, 802.4, and 802.5 subnetworks. In
- addition, Version 1 of GOSIP created a foundation upon which to build new
- protocols providing new services useful to Federal agencies.
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- Version 2 of GOSIP (FIPS 146-1) uses that foundation to provide a remote
- terminal access capability using the Virtual Terminal (VT) standard. At the
- network layer, Version 2 of GOSIP extends interoperabity to include ISDN
- subnetworks. Future versions of GOSIP will add new user services such as
- Directory Services, Transaction Processing, Electronic Data Interchange and
- Remote Data Base Access as well as allow interoperability among users served
- by other network technologies.
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- GOSIP does not mandate that government agencies abandon their favorite
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- computer networking products. GOSIP does mandate that government agencies,
- when acquiring computer networking products, purchase OSI capabilities in
- addition to any other requirements, so that multi-vendor interoperability
- becomes a built-in feature of the government computing environment, a fact of
- life in conducting government business.
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- The OSI protocols have the potential to change the way the Federal Government
- does business. It is essential that Federal agencies make a strategic
- investment in OSI beginning now, so that they will be well positioned to take
- advantage of the new services provided by the OSI protocols as they become
- available. Planning the integration of OSI may require considerable time and
- effort, but this work will be more than offset by the benefits provided by the
- new technology.
-
- 1.5 APPLICABILITY
-
- GOSIP specifies a set of OSI protocols for computer networking that is
- intended for acquisition and use by government agencies. It must be used by
- all Federal government agencies when acquiring products and services which
- provide equivalent functionality to the OSI protocols referenced in this
- document. For a more detailed statement of applicability, see FIPS 146.
-
- 1.6 GOSIP VERSION 2 FUNCTIONALITY
-
- Version 2 of GOSIP contains the following functionality not included in
- Version 1.
-
- 1. The Virtual Terminal Service (TELNET and Forms profiles);
- 2. The Office Document Architecture (ODA);
- 3. The Integrated Services Digital Network (ISDN);
- 4. The End System-Intermediate System protocol (ES-IS), and as user
- options;
- 5. The Connectionless Transport Service (CLTS); and,
- 6. The Connection-Oriented Network Service (CONS).
-
- The compliance information for GOSIP Version 2 functions is stated in the FIPS
- announcement. Since the Connectionless Transport Service and the Connection-
- Oriented Network Service are provided as optional user services, there is no
- mandatory compliance specified. All GOSIP protocols not included in the above
- list are bound by the GOSIP Version 1 compliance date which is August 15,
- 1990. Figure 3.1 illustrates the GOSIP Version 1 architecture and protocols.
- Figure 3.2 illustrates the GOSIP Version 2 architecture and protocols.
-
- 1.7 GOSIP Version 1 Errata
-
- 1. Since Version 1 of the Stable Implementation Agreements for OSI
- Protocols was published, errata have been added to those agreements, primarily
- by the FTAM and Upper Layer Special Interest Groups (SIGs) of the NIST OSI
- Implementors' Workshop to correct problems in the original agreements and to
- align with agreements being developed internationally. Version 1 of GOSIP
- will now reference the relevant sections of Version 3 of the Stable
- Implementation Agreements. Text for these sections is available from the
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- Government Printing Office and NTIS.
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- 2. Version 1 of GOSIP (section 5.3.2) required that private messaging
- systems within the government be capable of routing on administration name,
- private domain name, organization name, organization unit and personal name.
- The requirement that private messaging systems be capable of routing based on
- personal name has been deleted. This change expands the range of messaging
- systems that are GOSIP compliant.
-
- 3. GOSIP Version 1 implementations should use the Network Service Access
- Point (NSAP) Address structure in Figure 5.1.3 of GOSIP Version 2. This
- change was made to align with the routing standards currently being developed
- by the ISO.
-
- 4. Version 1 of GOSIP (section 4.2.3) required that processing of
- Protocol Data Units by the Connectionless Network Layer Protocol be in order
- of priority. This requirement has been deleted.
-
- 5. Version 1 of GOSIP describes a general architecture for OSI security,
- defines a set of optional security services that may be supported within the
- OSI model, and outlines a number of mechanisms that can be used in providing
- the service. Users should now refer to the updated Security Options section
- in Version 2 of GOSIP. It should be noted that, even in Version 2 of GOSIP,
- the security section is optional and is considered a placeholder for future
- security specifications.
-
- 1.8 SOURCES OF PROTOCOL SPECIFICATIONS
-
- 1.8.1 Primary Source
-
- The primary source of protocol specifications in GOSIP is the Stable
- Implementation Agreements for Open Systems Interconnection Protocols [NIST 1].
- This source document was created and is maintained by the NIST Workshop for
- Implementors of Open Systems Interconnection. It provides implementation
- specifications that are derived from service and protocol standards issued by
- the International Organization for Standardization (ISO), the Consultative
- Committee for International Telegraphy and Telephony (CCITT), and the
- Institute of Electrical and Electronics Engineers, Inc. (IEEE).
-
- By primary source, it is meant that where GOSIP uses a given protocol, it
- cites that protocol by reference as specified in the above-named Workshop
- Agreements. The primary source is used in all instances where the protocol of
- interest has been specified in the Workshop Agreements. Section 4 of this
- profile gives conformance statements for each protocol that, in some cases,
- are augmented from the minimal conformance statements in the Workshop
- Agreements in order to provide the functionality required for government
- computer networking.
-
- 1.8.2 Secondary Sources
-
- GOSIP must be complete in that open systems procured in accordance with it
- must interoperate and must provide service generally useful for government
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- computer networking applications. The Workshop Agreements continue to evolve,
- but they are still incomplete. (The appendices of GOSIP cite needed work.)
- Thus, where the Workshop Agreements do not provide completeness, GOSIP may
- augment protocol and service specifications from the following sources, listed
- in precedence order.
-
- o International Standards and Recommendations
- o Draft International Standards
-
- Since this profile is one of open systems, the secondary sources include
- specifications that are international standards or are advancing to become
- international standards. They are included in GOSIP, where needed, to help
- satisfy the criterion of completeness, and thus, utility. Note that secondary
- sources exclude protocols, however mature, that are not a part of the
- international standards process.
-
- 1.8.3 Tertiary Sources
-
- Even the secondary sources named above may not provide a complete and useful
- networking system today. It may be necessary for GOSIP to augment protocol
- and service specifications from the following sources, listed in precedence
- order.
-
- o ANSI Standards
- o Draft Proposed International Standards
- o Federal Information Processing Standards
- o Military Standards
-
- For example, security protocols might be incorporated from a FIPS issued by
- NIST. The use of protocols from other than the primary and secondary sources
- is undesirable. It is expressly intended that these omissions from standards
- work be brought to the attention of the international standards bodies so that
- acceptable international standards may be developed as rapidly as possible.
- The GOSIP Advanced Requirements Group will replace all tertiary source
- protocols in GOSIP with suitable primary and secondary source substitutes,
- when available.
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- 2. TESTING OF GOSIP-COMPLIANT PRODUCTS
-
-
- Conformance testing verifies that an implementation acts in accordance with a
- particular specification, such as GOSIP. Interoperability testing duplicates
- the "real-life" environment in which an implementation will be used.
- Performance testing measures whether an implementation satisfies the
- performance criteria of the user. Functional testing determines the extent to
- which an implementation meets user functional requirements.
-
- NIST issued GOSIP Version 1.0 testing guidance in GOSIP Conformance and
- Interoperation Testing and Registration [NIST 8]. Consult that reference for
- detailed procedures, instructions for GOSIP product suppliers, and
- recommendations for Acquisition Authorities. A future revision to GOSIP
- Conformance and Interoperation Testing and Registration will add procedures,
- instructions, and recommendations for the new protocols included in GOSIP
- Version 2.0. Until such revision occurs, Federal agency personnel should use,
- for testing GOSIP Version 2.0 additions, the interim guidance supplied below
- in sections 2.1 and 2.2.
-
- NIST issued Message Handling Systems Evaluation Guidelines [NIST 9] to assist
- Federal agency personnel to evaluate the degree to which specific Message
- Handling Systems products meet the specific performance and functional
- requirements of an agency procurement. Further guidelines are planned; File
- Transfer, Access and Management will be the next. If a guideline is not yet
- available for an application of interest, Federal agency personnel should use
- the interim guidance supplied in sections 2.3, 2.4, and 2.5.
-
- 2.1 CONFORMANCE TESTING
-
- Conformance is shown by the vendor having passed conformance tests adequate
- for the purpose of exercising the functional units specified in section 4.
- Conformance to the GOSIP will only apply to the profile defined by the
- Acquisition Authority. For the purposes of testing conformance to the
- protocols required by GOSIP Version 2.0, the Acquisition Authority will
- provide documentation which identifies specific testing requirements.
-
- Conformance tests and test systems are currently being developed by several
- testing organizations. When these test systems for GOSIP Version 2.0 are
- completed, NIST will specify the tests, test systems and testing organizations
- that are accredited to perform conformance testing of GOSIP protocols.
-
- For the interim, the Acquisition Authority shall require that vendors
- substantiate any claim of GOSIP conformance.
-
- The Acquisition Authority shall also be responsible for determining that
- acceptable test results are available as a prerequisite to awarding of a final
- procurement contract.
-
- 2.2 INTEROPERABILITY TESTING
-
- The Acquisition Authority should specify a detailed set of requirements that
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- will serve to test interoperability of GOSIP Version 2.0 protocols. The
- Acquisition Authority must specify the following for this testing:
-
- - the products to be used for the interoperability testing,
- including hardware and software versions and components,
-
- - a detailed description of planned test scenarios to be run between
- implementations in the interoperability testing, including the
- results expected, and
-
- - criteria for passing or failing the testing.
-
- NIST will recommend vehicles particularly suitable for interoperability
- testing.
-
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- 2.3 PERFORMANCE TESTING
-
- The principal thrust of OSI is to provide interworking of distributed
- applications using heterogeneous, multi-vendor systems. GOSIP does not cite
- performance criteria. Note that protocol definitions include quality of
- service parameters and other tunable functions. The Acquisition Authority
- must determine and specify those performance related features that are desired
- to be under user or application process control and those desired to be under
- system operator control. The Acquisition Authority may also wish to specify
- benchmarking criteria as evidence of satisfying performance requirements.
-
- 2.4 FUNCTIONAL TESTING
-
- The GOSIP specification mandates for each protocol a minimum set of functions
- to meet general government requirements. In many instances additional
- functions might be supported within the Workshop Agreements and/or the
- protocol standard. The Acquisition Authority must determine and specify such
- additional functions that are required within an acquisition. The Acquisition
- Authority is responsible for determining that the vendor products proposed
- meet any and all functional requirements.
-
- 2.5 VENDOR ENHANCEMENTS
-
- It is expected that most vendors will update their products, for example, from
- a Draft International Standard version to an International Standard version,
- as implementation specifications are completed in the Workshop Agreements.
- Also, some vendors may provide additional functionality. Implementations that
- go beyond the functional units stated in section 4 must be implemented
- according to the Workshop Agreements and must interwork with implementations
- that strictly comply with section 4. Requests For Proposals should encourage
- vendor enhancements where required to meet user needs.
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- 3. DESCRIPTIONS OF ARCHITECTURE AND PROTOCOLS
-
-
- This section briefly describes the GOSIP architecture and protocols. For a
- more thorough understanding, consult the Government Open Systems
- Interconnection User's Guide [NIST 7] and other references cited in this
- profile.
-
- 3.1 ARCHITECTURE DESCRIPTION
-
- Figure 3.1 illustrates the GOSIP Version 1 architecture and protocols. Figure
- 3.2 shows how new protocols providing new services have been added to GOSIP
- Version 2 while maintaining compatibility with GOSIP Version 1.
-
- Achieving OSI within the government is best accomplished by using a single
- method (one protocol profile at each OSI layer) to perform the functions of
- routing and reliable data transfer. Fig. 3.2 shows that these functions are
- provided by the transport class 4, and connectionless network layer protocols.
- Mandatory use of a single transport protocol class (class 4) and a
- connectionless network layer protocol (CLNP) assures interoperable data
- transfer between government computer systems for a variety of applications
- across a variety of subnetwork technologies. Optional use of additional
- transport and network layer protocols is not precluded by GOSIP; in fact, as
- shown in Figure 3.2, GOSIP now includes specifications for an optional
- connectionless transport service and an optional connection-oriented network
- service. The specifications give sufficient detail for achieving interworking
- among government computer systems implementing these options.
-
- It is useful to enable user selection from among a set of lower layer
- subnetwork technologies for local and wide area networking. These different
- technologies exhibit physical, performance, and cost differences that render
- one technology more appropriate than others for particular uses. Fig. 3.2
- illustrates six subnetwork technologies specified by GOSIP. These are the
- packet data network (X.25), the point to point (Pt-Pt) LAP B Subnetwork, the
- Integrated Services Digital Network (ISDN), the Token Bus (ISO 8802/4), the
- Token Ring (ISO 8802/5) and the Carrier Sense Multiple Access with Collision
- Detection (ISO 8802/3). When a point to point or local area subnetwork
- technology is selected, the CLNP end system to intermediate system (CLNP ES-
- IS) routing protocol [ISO 44] is also required. Other lower layer subnetwork
- technologies may be used, but the Acquisition Authority must provide proper
- specification to ensure procurement of an effective product, that is, a
- product able to support operation of transport class 4, the connectionless
- network protocol, and the GOSIP upper layer protocols.
-
- Interconnection of multiple wide-area networks to form the appearance of a
- single logical wide-area network may be accomplished by any technically
- appropriate means such as X.75 gateways. Interconnection of remote local area
- networks to form the appearance of a single logical network may be
- accomplished by any technically appropriate means, such as MAC bridges. In
- all other instances, the GOSIP mandates subnetwork interconnection by means of
- the CLNP and the network access methods appropriate for the specific networks
- being interconnected.
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- At the application layer, many protocols are expected to be included in GOSIP
- over time, each applying to different uses. In Fig. 3.2, the current
- application protocols are File Transfer, Access and Management (FTAM) based on
- the ISO International Standard [ISO 16-19], the Basic Class Virtual Terminal
- Protocol based on the ISO International Standard [ISO 32-35], and Message
- Handling Systems based on the 1984 CCITT Recommendations [CCITT 2-9]. Each
- application may require a different selected set of services from the
- application control service elements and the presentation and session control
- layers. Thus, layers 5, 6, and 7 may be thought of as an integral package of
- GOSIP upper layer protocols for each specific application.
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- Figure 3.1 GOSIP Version 1 OSI Architecture
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- Figure 3.2 GOSIP Version 2 OSI Architecture
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- The Office Document Architecture (ODA) standard based on the ISO International
- Standards [ISO 36-42, CCITT 17-24] is also included in GOSIP. Although ODA is
- not an OSI protocol, it is included in GOSIP because it provides services
- required by Federal agencies, and the information specified by the standards
- can be transported by the OSI FTAM and MHS Application layer protocols.
-
- A goal of this profile is to permit an Acquisition Authority to issue
- unambiguous procurement requests for standard applications operating over
- networks using standard protocols. The Acquisition Authority determines the
- required applications and the required networks and the GOSIP defines the
- required protocols. For example, if an Acquisition Authority requires a
- general purpose File Transfer Access and Management application on a CSMA/CD
- subnetwork, the GOSIP defines that layer 7 FTAM is required along with certain
- services from the application control service elements, presentation, and
- session protocols. To perform the data transfer function, GOSIP mandates the
- Class 4 transport protocol and the connectionless network layer protocol, and
- defines a subset of the ISO 8802/2 link layer, and the ISO 8802/3 CSMA/CD
- protocol.
-
- 3.2 PROTOCOL DESCRIPTIONS
-
- Following are brief narratives of the general services provided by protocols
- in each layer of the GOSIP architecture to the layer above.
-
- The Application layer (layer 7) allows for protocols and services required by
- particular user-designed application processes. Functions satisfying
- particular user requirements are contained in this layer. Representation and
- transfer of information necessary to communicate between applications are the
- responsibility of the lower layers. See References [NIST 1; ISO 1, 16-19, 22-
- 25, 32-35; CCITT 2-9, 14].
-
- The Presentation layer (layer 6) specifies or, optionally, negotiates the way
- information is represented for exchange by application entities. The
- presentation layer provides the representation of: 1) data transferred between
- application entities, 2) the data structure that the application entities use,
- and 3) operations on the data's structure. The presentation layer is
- concerned only with the syntax of the transferred data. The data's meaning is
- known only to the application entities, and not to the presentation layer.
- See References [NIST 1; ISO 1,20,21,24,25].
-
- The Session layer (layer 5) allows cooperating application entities to
- organize and synchronize conversation and to manage data exchange. To
- transfer the data, session connections use transport connections. During a
- session, session services are used by application entities to regulate
- dialogue by ensuring an orderly message exchange on the session connection.
- See References [NIST 1; ISO 1,14,15; CCITT 12,13].
-
- The Transport layer (layer 4) connection-oriented service provides reliable,
- transparent transfer of data between cooperating session entities. The
- transport layer entities optimize the available network services to provide
- the performance required by each session entity. Optimization is constrained
- by the overall demands of concurrent session entities and by the quality and
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- 12
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- capacity of the network services available to the transport layer entities.
- In the connection-oriented transport service, transport connections have end-
- to-end significance, where the ends are defined as corresponding session
- entities in communicating end systems. Connection-oriented transport
- protocols regulate flow, detect and correct errors, and multiplex data, on an
- end-to-end basis. See References [NIST 1; ISO 1,12,13; CCITT 10,11]. The
- transport layer also supports a simple connectionless transport service [ISO
- 46-47].
-
- The Network layer (layer 3) provides message routing and relaying between end
- systems on the same network or on interconnected networks, independent of the
- transport protocol used. The network layer may also provide hop-by-hop
- network service enhancements, flow control, and load leveling. Services
- provided by the network layer are independent of the distance separating
- interconnected networks. See References [NIST 1,3; ISO 1-8,11; CCITT 1; NCS
- 1].
-
- The Data link layer (layer 2) provides communication between two or more
- (multicast service) adjacent systems. The data link layer performs frame
- formatting, error checking, addressing, and other functions necessary to
- ensure accurate data transmission between adjacent systems. Note that the
- data link layer can operate in conjunction with several different access
- methods in the physical layer. See Figure 3.2 for examples. See References
- [NIST 1-3,5; ISO 1,26,28; CCITT 1].
-
- The Physical layer (layer 1) provides a physical connection for transmission
- of data between data link entities. Physical layer entities perform
- electrical encoding and decoding of the data for transmission over a medium
- and regulate access to the physical network. See References [NIST 1-3; ISO 1;
- ISO 29-31; IEEE 1].
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- 4. PROTOCOL SPECIFICATIONS
-
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- 4.1 USE OF THE LAYERED PROTOCOL SPECIFICATIONS
-
- The individual protocol and interface specifications in this section shall be
- used directly in Requests For Proposals. However, Acquisition Authorities
- must take additional steps to ensure an adequate specification for their
- intended purpose. The following items must be supplied by the Acquisition
- Authority.
-
- 4.1.1 Protocol Selection
-
- The architecture described in section 3 suggests a range of protocol choices
- at different layers of the OSI Reference Model. A subset of these protocols
- may adequately satisfy an individual acquisition requirement, and may be used.
- If a subset of the protocols and interface profiles is chosen, it is the
- Acquisition Authority's responsibility to ensure that all paths through the
- architecture are complete, i.e., (1) that protocols from layer 1 through layer
- 7 are included for end systems and at least layers 1 through 3 are included
- for intermediate systems, and (2) that the appropriate service interface
- specifications for the selected protocols are also included, as indicated in
- section 4.1.2 below.
-
- With respect to selecting protocols, at least one lower layer technology must
- be chosen, i.e., CSMA/CD (carrier sense, multiple access with collision
- detection) [NIST 1, 2; ISO 28, 29], Token Bus [NIST 1; ISO 28, 30], Token
- Ring [NIST 1; ISO 28, 31]; X.25 [NIST 1, 3; CCITT 1; ISO 8]; HDLC LAP B point
- to point (Pt-Pt) subnetwork [ISO 26] or ISDN [NIST 1, ANSI 1-3, CCITT 25-27,
- ISO 45]. Additional lower layer technologies may be used to meet special
- requirements. The following protocol layers are mandatory for compliance with
- GOSIP: the connectionless network layer protocol, transport class 4, and
- session. Transport class 0 and the Connection Oriented Network Service (CONS)
- [ISO 2,3] are mandated only in conjunction with public data network messaging;
- see section 4.2.7.3, Message Handling Systems. Presentation protocol and
- association control service elements are required for all applications except
- messaging. At least one application layer specific protocol is required to
- support the intended application. For example, if messaging is required,
- specify MHS; if file transfer is required, specify FTAM; and, if the Virtual
- Terminal Service is required, specify VT. The provision of the CONS, for
- general use, and the Connectionless Transport Protocol (CLTP) are options that
- may be specified in addition to the GOSIP mandatory Connectionless Network
- Service (CLNS) and Transport (class 4), respectively. More detailed
- specification guidance is provided in sections 4.2 and 4.3.
-
- 4.1.2 Service Interface Requirements
-
- GOSIP mandates no service interface accessibility beyond that indicated in the
- Workshop Agreements; therefore, any additional service interface accessibility
- requirements must be clearly stated and mandated by the Acquisition Authority.
- For example, GOSIP mandates no specific direct access to transport services.
- If the Acquisition Authority requires direct access to transport services,
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- 14
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- such a requirement must be included in a solicitation. The issues involved in
- determining such a requirement are complex. Refer to the GOSIP Users' Guide
- for a discussion of these issues.
-
- Should the Acquisition Authority not request direct access to service
- interfaces, such access might or might not be provided at the discretion of
- individual vendors. For example, some vendors may provide access to session
- services, others may provide access to transport and network services, and
- still others may limit access to association control services only. Of
- course, some vendors may provide direct access to service interfaces at the
- human user interface only. When there is no requirement for a service
- interface between layers, vendors might merge multiple layer implementations.
- Such a merger is often implemented to accrue performance benefits to the user.
-
- Should the Acquisition Authority request direct access to a specific service
- interface, care should be taken to specify the general functional and
- operational objectives of the interface; otherwise, particular vendor
- interface implementations might or might not meet user requirements. While
- specifying the general functional and operational objectives for a service
- interface should enable the vendor to meet a user's functional requirements,
- such a specification will not ensure portability of software, written to the
- interface, across product lines from multiple vendors. Work underway in the
- IEEE 1003.8 POSIX networking services interface committee should create, in
- the future, a series of service interface specifications that will enable
- portability of software written to those specifications. In the interim,
- Acquisition Authorities requiring service interfaces that enable software
- portability must include a very detailed and explicit interface specification
- within the solicitation. Such a specification is difficult and expensive to
- produce, and will limit the number of vendors that bid on a solicitation.
- Thus, this practice is not recommended. A more prudent course, at the present
- time, is to specify the general functional and operational objectives of a
- service interface, leaving implementation decisions to the vendor.
-
- 4.1.3 Performance Requirements
-
- The Acquisition Authority must specify performance requirements. Performance
- of an open system is a function of: 1) the source end system, 2) the
- destination end system, and 3) the communications links, subnetworks, and
- intermediate systems between the two end systems. The Acquisition Authority's
- best strategy, given these difficult-to-control factors, is to specify
- performance requirements for the principal operating environment of the end
- system. For example, if the communicating end systems will generally be on
- the same token bus network, detailed performance profiles should be developed
- for that environment. If these systems must occasionally communicate over a
- packet data network between local area networks (LANs), then a test for
- correct interoperation in this occasional environment, without strict
- performance requirements, should also be included.
-
- 4.2 END SYSTEM SPECIFICATION
-
- 4.2.1 Physical Layer
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- GOSIP does not mandate any specific physical interface standard. However, the
- Acquisition Authority must specify physical layer requirements in a
- solicitation. The following interfaces are recommended. The three standards
- most commonly used in conjunction with X.25 are Electronic Industries
- Association (EIA) RS-232-C [EIA 1] for line speeds up to 19.2 kilobits/second,
- V.35 [CCITT 16] for line speeds above 19.2 kilobits/second, and EIA RS-530 for
- transfer rates above 20 kilobits/second. For IEEE 802 LANs, the physical
- interface characteristics are identified in ISO 8802/3 for CSMA/CD, ISO 8802/4
- for token bus, and ISO 8802/5 for token ring, [ISO 29-31]. Additional
- specifications for these interfaces, including subsets, options, and parameter
- settings are included in the Workshop Agreements [NIST 1]. For ISDN, GOSIP
- provides for the basic rate interface (BRI) at the S, T, and U reference
- points [ANSI 1-2] and the primary rate interface (PRI) at the U reference
- point [ANSI 3]. The BRI provides a 16 kilobits/second signalling (D) channel
- and up to two 64 kilobits/second switched (B) channels. The PRI provides a 64
- kilobits/second signalling (D) channel and up to twenty-three 64
- kilobits/second switched (B) channels.
-
- Other, non-proprietary, physical interface standards may be selected depending
- upon unique requirements of the Acquisition Authority; however, the
- Acquisition Authority must take special care to ensure appropriate operation
- of such interfaces within a procured system. The Acquisition Authority is
- advised to make a selection from the set of recommended physical interfaces.
-
- 4.2.2 Data Link Layer
-
- The data link layer protocols shall be selected by the Acquisition Authority
- from among the following: 1) High Level Data Link Control (HDLC) Link Access
- Procedure B (LAP B), in conjunction with X.25 [NIST 1,3; ISO 26] and Pt-Pt
- subnetworks; 2) ISO 8802/2 (LLC 1) in conjunction with ISO 8802/3, ISO 8802/4,
- or ISO 8802/5 [NIST 1; ISO 28], and 3) Q.921 (LAPD) [CCITT 25] for operation
- on the ISDN D channel and ISO 7776 (LAP B) for operation on ISDN B channels.
- These protocols shall conform to the Workshop Agreements.
-
-
-
-
- 4.2.3 Network Layer Service
-
- For GOSIP end systems, the connectionless network service (CLNS) is mandated
- for Government-wide interoperability and provides the required means of
- interconnecting logically distinct local and long-haul subnetworks. When a
- GOSIP end system is connected to a local area or Pt-Pt subnetwork, the CLNP
- end system to intermediate system (CLNP ES-IS) dynamic routing protocol is
- required. The connection-oriented network service is an option available to
- GOSIP end systems directly connected to an X.25 subnetwork or ISDN. The
- technology for providing X.25 and ISDN subnetworks may be used to support the
- mandated CLNS and the optional CONS; in either case certain subnetwork access
- protocols are required. These topics are elaborated in the following
- paragraphs.
-
- 4.2.3.1 Connectionless Mode Network Service
-
- 16
-
-
-
-
-
-
-
-
- The Connectionless Mode Network Service (CLNS) shall be provided by the ISO
- Connectionless Network Protocol (CLNP) [NIST 1; ISO 4,7]. The CLNP must be
- implemented and used for internetworking of concatenated subnetworks. For
- operation on a single logical subnetwork, the CLNP also must be implemented.
- When an end system is connected to a local area or Pt-Pt subnetwork the CLNP
- ES-IS protocol must be implemented and used.
-
- 4.2.3.1.1 Provision of the Connectionless Network Service
-
- This service shall be provided according to the Workshop Agreements, section
- 3.5, with the following modifications and additions:
-
- Add to the first bullet of section 3.5.1(2), the following:
-
- o An End System must provide a configuration mechanism to control
- the value to be assigned to the Lifetime parameter for PDUs which
- it originates.
-
- Replace the first bullet of section 3.5.1(3) Optional Functions with the
- following:
-
- o The use of the security parameter shall be in accordance with
- section 6 of this specification, if required by the Acquisition
- Authority.
-
- Add as section 3.5.2(4):
-
- o The CLNS shall be provided with interfaces to the 1984 CCITT
- Recommendation X.25, HDLC LAP B (ISO 7776), ISO 8802.2 and Draft
- International Standard (DIS) 9574 (ISDN), as selected by the Acquisition
- Authority. When interface to DIS 9574 is provided, the provisions of
- ISO 8878 are not used.
-
- Section 3.5.3 of the Workshop Agreements is to be implemented by those systems
- operating over X.25. Section 3.5.4 of the Workshop Agreements is to be
- implemented by those systems operating over ISDN.
-
- 4.2.3.1.2 Provision of The End System To Intermediate System Routing Service
-
- For end systems connected to local area and Pt-Pt subnetworks, the end system
- to intermediate system (CLNP ES-IS) routing service shall be provided by the
- ES-IS protocol ISO 9542 [ISO 44] implemented as specified in the Workshop
- Agreements section 3.8.1. For end systems connected to wide-area networks,
- provision of an end system to intermediate system routing service is network
- specific.
-
- 4.2.3.2 Connection-Oriented Network Service
-
- The CONS is an additional, optional service that may be specified for end
- systems that are directly connected to X.25 wide area networks and ISDNs. Use
- of this service can, under certain circumstances, avoid the overhead
-
- 17
-
-
-
-
-
-
-
- associated with CLNP and may permit interoperation with end systems that do
- not comply with GOSIP (i.e., do not implement CLNP). When an Acquisition
- Authority specifies the CONS option, CONS shall be provided by the X.25 Packet
- Level Protocol (PLP) [ISO 2]. The mapping of the elements of the CONS to the
- elements of the X.25 PLP is according to ISO 8878 [ISO 8]. This service shall
- be provided as specified in section 3.6.1 of the Workshop Agreements with the
- following modifications:
-
- o Section 3.6.1.3 does not apply.
-
- When providing CONS in an ISDN, the considerations for control of B and D
- channels shall be provided by DIS 9574 [ISO 45] and implemented according to
- section 3.6.1.4 of the Workshop Agreements.
-
- (Note that use of X.25 in GOSIP is consistent with FIPS 100-1 which requires
- CCITT X.25-1984, ISO 7776, and ISO 8202 until January 1, 1993. After that
- time, additional items covered in CCITT X.25-1988 are mandated by FIPS 100-
- 1.)
-
- 4.2.3.3 Network Layer Protocol Identification
-
- OSI systems require the ability to identify which OSI protocols and services
- are used in a particular instance of communication. These rules for
- identification are specified in ISO DTR 9577 [ISO 43]. GOSIP systems shall
- implement the protocol identification rules as specified in section 3.9.2.2 of
- the Workshop Agreements.
-
- 4.2.3.4 Special Provisions For Integrated Services Digital Networks
-
- Integrated services digital networks (ISDN) enables X.25 PLP data to be sent
- across the D channel, sharing the channel with signaling data, and across a B
- channel. The Acquisition Authority must specify whether one or both of these
- capabilities are required. When operation of X.25 over a B channel is
- selected, the B channel can be provided as a switched service or a permanent
- service. The Acquisition Authority must specify whether one or both of these
- capabilities are required.
-
- (Note that at the present time switched access to the B channel is available
- from most ISDN vendors, but not in a standard fashion; thus, multi-vendor
- interoperability between terminal equipment and switching equipment is not
- widely available today. Work underway in the North American ISDN Implementors'
- Workshop (IIW) is expected to improve this situation in the future. As
- appropriate IIW Agreements are developed, and related ISDN FIPS are issued by
- NIST, GOSIP will be updated accordingly.)
-
- ISDN provides the possibility of a BRI (16 Kbps D-channel + 2 64 Kbps B-
- channels) or a PRI (64 Kbps D-channel + 23 64 Kbps B-channels). The
- Acquisition Authority must specify whether BRI or PRI is required for each
- system. The BRI service interface might be available at the S, T, or U
- reference point. The Acquisition Authority must specify the physical
- interface required for each BRI system.
-
-
- 18
-
-
-
-
-
-
-
- ISDN B-channel services can be used by a GOSIP end system in any of six ways:
-
- 1) circuit-switched access to a packet handler integral to an ISDN
- switch;
- 2) circuit-switched access to a packet handler separate from an ISDN
- switch;
- 3) circuit-switched access directly to another GOSIP end system, or GOSIP
- intermediate system;
- 4) dedicated circuit access to a packet handler integral to an ISDN
- switch;
- 5) dedicated circuit access to a packet handler separate from an ISDN
- switch, and
- 6) dedicated circuit access to another GOSIP end system or GOSIP
- intermediate system.
-
- The Acquisition Authority must specify the B-channel access capabilities
- required for any GOSIP end system intended for use with ISDN B-channel
- services.
-
- For ISDN physical layer access at the S, T, and U reference points, sections
- 2.7.2.1 and 2.7.2.2 of the Workshop Agreements apply. For data link layer
- access on the D channel, section 2.7.2.4 of the Workshop
-
-
- Agreements applies. For signaling on an ISDN interface, section 2.7.2.5 of
- the Workshop Agreements applies. For data link layer access on a B channel,
- section 2.7.2.6 of the Workshop Agreements applies. The PLP for use on ISDN B
- and D channels shall be implemented as specified in section 2.7.2.7 of the
- Workshop Agreements.
-
- 4.2.4 Transport Layer
-
- For GOSIP end systems, the connection-oriented transport service (COTS), as
- provided by Transport class 4, is mandated for Government-wide
- interoperability and is the required means of providing a reliable end-to-end
- data communications path between end systems. The connectionless transport
- service (CLTS) is an option available for GOSIP end systems.
-
- 4.2.4.1 Connection-Oriented Transport Service
-
- The vendor shall provide Transport class 4 [NIST 1; ISO 12,13] according to
- section 4.5.1 of the Workshop Agreements, with the modifications and additions
- stated below. Transport class 0 [NIST 1; CCITT 10,11] is to be used as
- appropriate in accordance with the CCITT X.400 recommendations (see section
- 4.2.7.3 of this profile).
-
- Replace the sixth bullet of the Workshop Agreements section 4.5.1.2.1 with the
- following:
-
- o It is recommended that implementations not send user data in the
- CR or CC TPDU. Any user data received in a CR or CC TPDU will be
- made available to the Transport Service user.
-
- 19
-
-
-
-
-
-
-
-
- Replace the seventh bullet of the Workshop Agreements section 4.5.1.2.1 with
- the following:
-
- o It is recommended that implementations not send user data in the
- DR TPDU. Any user data received in a DR TPDU will be made
- available to the Transport Service user.
-
- Add, as the thirteenth bullet of the Workshop Agreements section 4.5.1.2.1,
- the following:
-
- o Transport expedited shall be provided as an optional service for
- the Transport Service user.
-
- In specifying operator and higher layer protocol access controls in transport,
- the Acquisition Authority should be guided by the implementation guide and
- military supplement [NIST 5,6].
-
- 4.2.4.2 Connectionless Mode Transport Service
-
- The Acquisition Authority may specifiy the optional connectionless mode
- transport service (CLTS) for GOSIP end systems [ISO 46]. This option may be
- specified only as an addition to the connection-oriented transport service.
- Although no GOSIP mandated protocols require the CLTS, a number of non-GOSIP
- protocols widely available in industry can use CLTS as an efficient means of
- communicating across local area networks. The Acquisition Authority must
- determine the need for CLTS to support non-GOSIP protocols.
-
- The CLTS option shall be implemented using IS 8602 [ISO 47] according to
- section 4.6 of the Workshop Agreements [NIST 1].
-
- 4.2.5 Session Layer
-
- The vendor shall provide the Session protocol as specified in section 5.9 and
- section 5.12 of the Workshop Agreements. Application layer protocols
- determine the session layer functional units needed for their support.
- Current and future needs should be considered when selecting Session layer
- functional units. [NIST 1; ISO 14,15; CCITT 12,13].
-
- 4.2.6 Presentation Layer
-
- The vendor shall provide the Presentation protocol as specified in section 5.8
- and section 5.12 of the Workshop Agreements. See References [NIST 1; ISO 20,
- 21, 24, 25].
-
- 4.2.7 Application Layer
-
- 4.2.7.1 Association Control Service Elements (ACSE)
-
- The ACSE, as specified in section 5.5 and section 5.12 of the Workshop
- Agreements, is required to support all applications except Message Handling
- Systems. See section 4.2.7.3 of this profile. See References [NIST 1; ISO
-
- 20
-
-
-
-
-
-
-
- 22-25]. Section 5.12.1.1 of the Workshop Agreements defines a fixed value for
- the Application Entity (AE) Title in order to satisfy the FTAM requirement for
- exchanging fields of this type; however, for compatibility with non-GOSIP
- systems, and to ease compatibility with future versions of GOSIP, GOSIP
- systems must allow locally configurable AE Titles to be generated and
- received.
-
- 4.2.7.2 File Transfer, Access, and Management Protocol (FTAM)
-
- The following categories of FTAM systems are defined for procurement purposes:
- (1) limited-purpose systems, and (2) full-purpose systems. These categories
- are defined by their support requirements given below. All FTAM systems in
- these categories are bound by the language and conditions for Phase 2 FTAM
- implementations contained in section 9 of the Workshop Agreements. [NIST 1]
- (Hereafter section 9.)
-
- A limited-purpose FTAM system provides the functions of simple file transfer
- and management. Such a system must support at least Implementation Profiles
- T1 (Simple File Transfer) and M1 (Management) as defined in section 9.
- Support requirements for Implementation Profiles are given in Table 9.7 of
- section 9. A full-purpose FTAM system provides the functions of positional
- file transfer (including simple file transfer), simple file access, and
- management. Such a system must support at least Implementation Profiles T2
- (Positional File Transfer), A1 (Simple File Access), and M1 (Management), as
- these are defined in section 9. A limited-purpose FTAM system is able to
- interoperate with a full-purpose FTAM system at the intersection of their
- capabilities.
-
- FTAM implementations (whether full-purpose or limited-purpose) can operate as
- an initiator of remote file activity, as a responder to requests for remote
- file activity, or as both initiator and responder. Further, FTAM
- implementations can operate as senders (of data to receivers), receivers (of
- data from senders), or as both. Thus, any of four possible roles may be
- assumed as follows: initiator-sendor, initiator-receiver, responder-sender,
- and responder-receiver. The Acquisition Authority must determine the
- requirements for each FTAM device and must specify such requirements in terms
- of initiator, responder, sender, and receiver, as well as in terms of limited-
- purpose or full-purpose.
-
- 4.2.7.3 Message Handling Systems
-
- The vendor shall provide all Message Transfer Services and Interpersonal
- Messaging Services specified in section 7 of the Workshop Agreements. [NIST 1]
- Communication between two Message Transfer Agents, one or both of which reside
- entirely and exclusively within a public message domain administered by a
- public data network, takes place as specified by CCITT Recommendation X.410
- (1984). CCITT mandates that transport class 0 and the Connection Oriented
- Network Service (CONS) [ISO 2, 3] be used by end systems when messaging over
- public messaging domains on public data networks. All end systems on private
- management domains must use transport class 4. Private management domain end
- systems that are also connected to public messaging domains conforming to
- CCITT Recommendation X.410 must also implement and use transport class 0 when
-
- 21
-
-
-
-
-
-
-
- acting as a messaging relay between the two domains. Specifically, the
- Message Transfer Agent in the system connected to both the private and public
- messaging domain performs the relay; there is no transport relay involved.
-
-
-
- 4.2.7.4 Virtual Terminal (VT) Basic Class
-
- The following categories of VT systems are defined for procurement purposes:
- 1) simple systems, and 2) forms capable systems. All VT systems in these
- categories are bound by the language and conditions contained in section 14 of
- the Workshop Agreements.
-
- A simple system provides the functions of a TTY compatible device. It
- supports a dialogue which is a simple line or character at a time. Such a
- system uses the control character (single) functions from the ASCII character
- set, such as "carriage return," "form feed," "horizontal tab," and "back
- space." A simple system supports the TELNET profile specified in section
- 14.8.1 of the Workshop Agreements. The TELNET profile requires the
- Asynchronous mode (A-mode) of operation (i.e., no token handling protocols are
- needed) and specifies simple delivery control.
-
- A forms-capable system is intended to support forms-based applications with
- local entry and validation of data by the terminal system. A forms-capable
- system supports functions such as "cursor movement," "erase screen," and
- "field protection." A forms-capable system supports the forms profile
- specified in section 14.8.3 of the Workshop Agreements. The forms profile
- requires the Synchronous mode (S-mode) of operation and specifies simple
- delivery control.
-
- The Basic Class VT International Standard [ISO 32] specifies three negotiation
- options which are independent of the VT profiles. These are No Negotiation,
- Switch Profile, and Multiple Interaction Negotiation. Multiple Interaction
- Negotiation is not addressed by the Workshop Agreements, but any system
- claiming support of this negotiation option must also support the Switch
- Profile and No Negotiation options. Any system supporting Switch Profile
- Negotiation must also support the No Negotiation option. Seven bit USASCII,
- as well as the International Reference Version (IRV) of ISO-646 graphic
- repertoires, must be supported by both simple and forms capable systems.
-
- 4.2.8 Exchange Formats
-
- Exchange formats are not OSI standards. They are included in GOSIP because
- the information that they describe can be transported by the OSI FTAM and MHS
- protocols either as the content of a file or as the body part of a message.
- The GOSIP contains only that information about exchange formats that are
- required to provide this capability. For detailed specifications on the
- exchange formats, consult the appropriate standards documents or the Workshop
- Agreements.
-
- Version 2 of GOSIP includes information on how to identify and transport the
- ODA exchange format. Future versions of GOSIP will include information on how
-
- 22
-
-
-
-
-
-
-
- to identify and transport additional formats such as Computer Graphics
- Metafile (CGM) and the Standard General Markup Language (SGML). For further
- details, see Appendix 4.
-
- ODA information can also be transported by other mechanisms which are outside
- the scope of the GOSIP.
-
- 4.2.8.1 Office Document Architecture (ODA)
-
- The ODA Standard [ISO 36-42, CCITT 17-24] specifies rules for describing the
- logical and layout structures of documents as well as rules for specifying
- character, raster, and geometric content of documents, thus, providing for the
- interchange of complex documents. The interchanged documents may be in
- formatted form (i.e., for presentation such as printing, displaying), in
- processable form (i.e., for further processing such as editing) or in
- formatted processable form (i.e., for both presentation and further
- processing).
-
- To transfer an ODA file, the services provided by either the MHS or FTAM
- application can be used.
- If the MHS application is used, OdaBodyParts are encoded for transmission over
- a CCITT X.400-1984 service as a single body part with tag 12 in the P2
- protocol.
-
- Oda [12] IMPLICIT OCTETSTRING
-
- The content of the OCTETSTRING is a SEQUENCE of OdaBodyPart Parameters and
- OdaData components with a value of type OdaBodyPart.
-
- OdaBodyPart :: = SEQUENCE {
- OdaBodyPart Parameters,
- OdaData }
-
- The OdaBodyPart Parameters component is a SET containing the document-
- application-profile and the document-architecture-class identifiers
-
- OdaBodyPart Parameters :: = SET {
- document-application profile [0] IMPLICIT OBJECT IDENTIFIER
- document-architecture-class [1] IMPLICIT INTEGER {
- formatted (0),
- processable (1),
- formatted-processable (2) }}
-
- The OdaData component is a SEQUENCE of Intercharge-Data Element as defined by
- IS 8613-5 [ISO 39]
-
- OdaData :: = SEQUENCE of Interchange-Data-Element
-
- In the P1 protocol, both the undefined bit (bit 0) and the ODA bit (bit 10) of
- the Encoded Information Type must be set when an ODA document is present in
- P2.
-
-
- 23
-
-
-
-
-
-
-
- When using FTAM to transfer an ODA file, the FTAM-3 (ISO FTAM unstructured
- binary) document type should be specified; however, since files that are not
- ODA files can have the same document type, it is left up to the user of
- application programs that remotely access files using FTAM to know that a
- given file contains ODA information.
-
- 4.3 INTERMEDIATE SYSTEM SPECIFICATION
-
- Intermediate systems shall operate in connectionless mode. That is, the
- connectionless network protocol is used regardless of whether the underlying
- technology operates in connectionless (e.g., CSMA/CD, token ring) or
- connection-oriented (e.g., X.25, LAP B) mode; however, the connectionless mode
- need not be used to interconnect X.25 subnetworks to form a single logical
- subnetwork. Also note that local area network bridges may be employed to form
- a single logical subnetwork.
-
- Intermediate systems may use any combination of the lower layer technologies
- as specified in the above sections of this profile: 4.2.1 Physical Layer,
- 4.2.2 Data Link Layer, and 4.2.3 Network Layer. That is, agencies may
- interconnect local and wide area networks. Implementation profiles for these
- protocols are contained in the Workshop Agreements and are referenced in the
- above sections of this profile. Implementation specifications for
- connectionless-mode intermediate systems are given in section 3.5 of the
- Workshop Agreements.
-
- Addressing structure and Address Registration Authorities are specified in
- section 5 of this profile.
-
- A system that serves as both end system and intermediate system must satisfy
- the mandatory requirements of sections 4.2 and 4.3 of this profile.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 24
-
-
-
-
-
-
-
- 5. ADDRESSING REQUIREMENTS
-
-
- 5.1 NETWORK LAYER ADDRESSING AND ROUTING
-
- This section specifies the Network Layer addressing scheme and its
- administrative and routing implications. It also identifies authorities
- responsible for the administration of the scheme and how subauthorities will
- be assigned and which responsibilities shall be delegated to them.
-
- 5.1.1 NSAP Address Administration, Routing Structures and NSAP Address
- Structure
-
- Network Service Access Point (NSAP) addresses specify the points where the
- communication capability of the Network Layer (i.e., the Network Service) is
- made available to its users. In effect they address the direct users of the
- Network Service, normally transport entities. The semantics of NSAP addresses
- are encoded into Network Protocol Address Information (NPAI) and conveyed in
- the appropriate protocol data units (PDUs) between protocol entities providing
- the Network Service.
-
- The basic principles of Network Layer addressing, as defined in Addendum 2 to
- the Network service definition [ISO 5], include:
-
- o NSAP address administration is based on the concept of
- hierarchical Addressing Domains. An Addressing Domain is a set of
- addresses interrelated by virtue of being administered by a common
- authority. The term authority refers to the entity that specifies
- the structure and ensures the uniqueness of identifiers in the
- associated domain. In practice the structure of NSAP addresses
- reflects this administrative hierarchy in that, at any level of
- the hierarchy, an initial part of the address unambiguously
- identifies the Addressing (sub) Domain.
-
- o The first three levels of the NSAP
- addressing domain are standardized and
- result in the NSAP address structure in
- Figure 5.1.1. The Initial Domain Part
- (IDP) of the address consists of two
- parts, the Authority and Format Identifier
- (AFI) and the Initial Domain Identifier
- (IDI). The AFI specifies the format of
- the IDI, the authority that is responsible
- for allocating IDI values, and the syntax
- used to represent the Domain Specific Part
- (DSP). The IDI is interpreted according
- to the value of the AFI and its value
- identifies the authority responsible for
- the structure and assignment of DSP
- values. The DSP is allocated and assigned
- by the authority specified by the IDP
- part.
-
- 25
-
-
-
-
-
-
-
-
-
- ZDDDDDDDDDDDDDDDD?
- 3 IDP 3
- CDDDDDDDDBDDDDDDDEDDDDDDDDDDDDDDDDDDDDDDDDD?
- ISO/CCITT NSAP ADDRESS 3 AFI 3 IDI 3 DSP 3
- @DDDDDDDDADDDDDDDADDDDDDDDDDDDDDDDDDDDDDDDDY
-
- Figure 5.1.1 NSAP Address Structure
-
-
- The National Institute of Standards and Technology (NIST) has been designated
- as the authority to administer the addressing domain identified by IDI value
- 0005 under AFI 47. The AFI value of decimal 47 specifies that the IDI part is
- interpreted as a four decimal digit International Code Designator (ICD) and
- that the DSP has a binary abstract syntax. ICDs are allocated and assigned by
- ISO [ISO 27] and identify international organizations that are the authorities
- for address administration for an addressing subdomain.
-
- The addressing domain identified by ICD 0005 shall be available for use by all
- of the Federal Government. The NIST shall specify the structure and semantics
- of the DSP associated with ICD 0005 and delegate the task of administering the
- assignment of DSP values to the General Services Administration (GSA). This
- is summarized in Figure 5.1.2.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 26
-
-
-
-
-
-
-
- ZDDDDDDDDDDDDDD?
- 3 IDP 3
- CDDDDDDDBDDDDDDEDDDDDDDDDDDDDDDDDDDD?
- ISO/CCITT NSAP Address 3 AFI 3 IDI 3 DSP 3
- CDDDDDDDEDDDDDDEDDDDDDDDDDDDDDDDDDDD4
- Fed. Govt. NSAP Address 3 47 3 0005 3structure specified 3
- 3 3 3by GOSIP 3
- @DDDDDDDADDDDDDADDDDDDDDDDDDDDDDDDDDY
-
- Figure 5.1.2 The NIST ICD Addressing Domain
-
-
- NSAP addresses, encoded as NPAI in appropriate NPDUs, serve as the primary
- input to the routing and relaying functions of protocol entities providing the
- Network Service. As such, the semantics of NSAP addresses must convey
- information required for routing as well as address administration.
-
- The basic principles of Network Layer routing, as defined in the OSI Routing
- Framework [ISO 48], include:
-
- o The global OSI environment will consist of a number of Administrative
- Domains. An Administrative Domain consists of a collection of End
- Systems (ESs) and Intermediate Systems (ISs), and subnetworks
- operated by a single entity or Administrative Authority. The
- Administrative Authority is responsible for the organization of ESs
- and ISs into Routing Domains; the further structuring and assignment
- of NSAP addresses; the policies that govern the information that is
- collected and disseminated both internally and externally to the
- Administrative Domain; and, the establishment of subdomains and the
- corresponding delegation of responsiblities.
-
- o A Routing Domain is a set of ESs and ISs which operate
- according to the same routing procedures and which is wholly
- contained within a single Administrative Domain. An
- Administrative Authority may delegate to the entity
- responsible for a Routing Domain the responsibilities to
- further structure and assign NSAP addresses. The
- hierarchical decomposition of Routing Domains into
- subdomains may greatly reduce the resources required in the
- maintenance, computation and storage of routing information.
-
-
- This GOSIP makes provisions for the establishment of Administrative Domains,
- Routing Domains and one level of routing subdomains (called Areas). This
- decomposition of the routing environment allows, where appropriate,
- administrative entities to request the delegation of responsibility for the
- organization and administration of their systems and subnetworks. The
- provision of two levels of routing structures within an Administrative Domain
- will allow Administrative Authorities to engineer routing configurations that
- best serve their individual needs.
-
- Figure 5.1.3 depicts the GOSIP NSAP address structure. This structure is
-
- 27
-
-
-
-
-
-
-
- mandatory for addresses allocated from the ICD 0005 addressing domain.
-
-
-
- ZDDDDDDDDDDDDDD?
- 3 IDP 3
- CDDDDDDBDDDDDDDEDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD?
- 3 AFI 3 IDI 3 DSP 3
- CDDDDDDEDDDDDDDEDDDDDDDDDDDBDDDDDDDDDDDDDDDDDBDDDDDDDDDDDDDBDDDDDDDDDDDDDDDDDDBDDDDDDBDDDDDDDDDDDDDDDBDDDDDDDD4
- 3 47 3 0005 3 DFI 3 Admin Author. 3 Reserved 3 Routing Domain 3 Area 3 System 3 NSel 3
- CDDDDDDEDDDDDDDEDDDDDDDDDDDEDDDDDDDDDDDDDDDDDEDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDEDDDDDDEDDDDDDDDDDDDDDDEDDDDDDDD4
- Octets 3 1 3 2 3 1 3 3 3 2 3 2 3 2 3 6 3 1 3
- @DDDDDDADDDDDDDADDDDDDDDDDDADDDDDDDDDDDDDDDDDADDDDDDDDDDDDDADDDDDDDDDDDDDDDDDDADDDDDDADDDDDDDDDDDDDDDADDDDDDDDY
-
- Figure 5.1.3 GOSIP NSAP Address Structure
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 28
-
-
-
-
-
-
-
- The DSP Format Identifier (DFI) specifies the structure, semantics and
- administration requirements associated with the remainder of the DSP. This
- field provides for graceful support of future DSP structures should the need
- arise. Currently, only one DSP format (DFI=10000000) is defined under ICD
- 0005. The remainder of this section describes this DSP format.
-
- The Administrative Authority field identifies the entity that is responsible
- for the organization of ISs and ESs into Routing Domains and Areas; the
- allocation and assignment of the remaining portion of the DSP; and the
- policies that govern the dissemination of information within and external to
- the Administrative Domain. Note that it is unlikely that a large number of
- Federal Government organizations will establish their own Administrative
- Domains. Instead, it is more likely that Administrative Domains will be
- established for collective organizations that autonomously operate large
- inter-networks and that individual organizations would correspondingly be
- delegated authority for Routing Domains or Areas.
-
- The Reserved field is positioned to be available for encoding higher level
- routing structures above those of the routing domain or to be used to expand
- either the Administrative Authority or the Routing Domain fields in future DSP
- formats should the need arise.
-
- The Routing Domain field identifies a unique Routing Domain within an
- Administrative Domain.
-
- The Area field identifies a unique subdomain of the Routing Domain.
-
- The System field identifies a unique system (ES or IS) within an Area. The
- format, value, structure and meaning of this field is left to the discretion
- of its administrator.
-
- The NSAP Selector field identifies a direct user of the Network Layer service,
- usually a Transport entity. (The NSAP Selector may also identify other direct
- users of the Network Service if required by the Acquisition Authority.)
- GOSIP allows a system administrator to configure NSAP Selector-to-Transport
- entity mappings because, for example, several transport entities may co-exist
- in some systems.
-
- 5.1.2 NSAP Address Registration Authorities
-
- This section names the GSA as the GOSIP Address Registration Authority, and
- specifies how subauthorities shall be assigned, and which responsibilities
- transfer to them.
-
- Under its delegated authority as Address Registration Authority for ICD 0005,
- GSA shall, upon request, assign, maintain, and publicize unique Administrative
- Authority identifiers for Federal Government entities that require distinct
- Administrative Domains. Contact GSA at:
-
- Telecommunications Customer Requirements Office
- U. S. General Services Administration
- IRMS
-
- 29
-
-
-
-
-
-
-
- Office of Telecommunications Services
- 18th & F Sts. N.W.
- Washington, D. C. 20405
-
- for the procedures for requesting the assignment of an Administrative
- Authority identifier. They are also included in Version 2 of the GOSIP User's
- Guide.
-
- 5.1.2.1 Responsibilities Delegated by NIST
-
- The management responsibilities delegated by the NIST, via the GSA, to Federal
- Government entities issued an Administrative Authority identifier under ICD
- 0005 are given below.
-
- o The entity must designate and register with the GSA a specific
- point of contact for its Administrative Authority.
-
- o The entity must ensure that procedures exist to establish
- appropriate routing structures and to delegate, if required,
- responsibliities to the administrators of individual Routing
- Domains or Areas.
-
- o The entity must ensure that addresses are assigned uniquely and
- are kept current and accurate.
-
- o The entity must ensure that policies are defined and procedures
- exist for making addresses and routing information known to other
- administrative domains.
-
- o The entity may, on a voluntary basis, supply such
- information to the GSA for government-wide compilation
- and dissemination. The GOSIP Users' Guide [NIST 7]
- lists the factors that Administrative Authorities
- should consider before requesting this service and the
- procedures to be followed if the service is required.
-
- 5.1.3 GOSIP Routing Procedures
-
- This GOSIP specifies dynamic routing procedures for the exchange of
- configuration information between ESs and ISs connected via local area and
- point to point (pt-pt) subnetworks and hierarchical, static routing procedures
- for the establishment of routing information among ISs. These routing
- procedures shall be provided according to section 3.8 of the Workshop
- Agreements, with the following additions after the paragraph of section 3.8.2:
-
- o The Routing Information Base (RIB) shall be capable of associating
- arbitrary sets of NSAPs, described as NSAP address prefixes, with
- next hop forwarding information for use by the ISO 8473 Route PDU
- Function. In addition, the RIB must be capable of supporting a
- default entry that is used in forwarding PDUs containing
- destination NSAP addresses that do not match any other RIB
- entries.
-
- 30
-
-
-
-
-
-
-
-
- Nonstandard dynamic routing procedures, in addition to the static capabilities
- specified above, may be used to establish RIBs within ISs in the interim
- period while OSI IS-IS dynamic routing protocols are still under development.
- It should be noted that the GOSIP supported routing structures and DSP
- addressing structure are in alignment with the OSI IS-IS intra-domain routing
- protocol [ISO 49] currently under development and that later versions of this
- profile will mandate the use of standardized OSI IS-IS routing protocols.
-
- The routing procedures required for GOSIP systems to communicate with non-
- GOSIP OSI-compliant systems are discussed in Version 2 of the GOSIP User's
- Guide.
-
- 5.2 UPPER LAYERS ADDRESSING
-
- The following sections provide guidance on certain upper layer addressing
- issues.
-
- 5.2.1 Address Structure
-
- The address structure for the Session Service Access Point (SSAP) and
- Transport Service Access Point (TSAP) Selector is two octets for each field,
- encoded in binary as shown on Fig. 5.2.1. Other lengths conforming to the
- limits specified in the Workshop Agreements, may be assigned by an end system
- administrator.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 31
-
-
-
-
-
-
-
- PSAP SSAP TSAP
- ZDDDDDDDDDDDD? ZDDDDDDDDDDDD? ZDDDDDDDDDDDD?
- 3 binary 3 3 binary 3 3 binary 3
- @DDDDDDDDDDDDY @DDDDDDDDDDDDY @DDDDDDDDDDDDY
- 2 octets 2 octets 2 octets
-
- Figure 5.2.1 Upper Layers Address Structure
-
- 5.2.2 Address Assignments
-
- Service access point (SAP) selectors specify the addresses of standard service
- interfaces. Values are assigned by an end system administrator and must be
- configurable in GOSIP end systems. T-selectors and S-selectors are each
- encoded as a string of octets. The octet string may be specified as an
- unsigned integer; if so, the high order octet precedes low order octets. P-
- selectors are encoded in Abstract Syntax Notation (ASN).1 type OCTETSTRING as
- per the Presentation protocol specification [ISO 21].
-
- The Application Context Name can be used to distinguish the Application
- entities that use the common application services of ACSE. The Application
- Context Names for FTAM and VT, as specified in sections 5.12.1.1 and section
- 5.12.1.4 of the Workshop Agreements, are "ISO FTAM" and "ISO VT." Note that
- applications which require additional Application Context information may
- define them, even if they make use of FTAM and/or VT.
-
- 5.2.3 Address Registration
-
- As an interim measure, until Directory Service implementations are available,
- federal agencies that wish to have their PSAP address (upper layer SAP
- selector values plus full NSAP address) accessible to other agencies may
- register these addresses with GSA. GSA shall catalog, maintain, and
- disseminate these addresses.
-
- 5.3 IDENTIFYING APPLICATIONS
-
- 5.3.1 FTAM and File Transfer User Interface Identification
-
- The FTAM service definition [ISO 18] includes an optional parameter called the
- initiator identity. GOSIP recommends the use of this parameter in FTAM
- implementations to identify users of the service. Generally, an identifying
- name or group of names is provided in this field. The name identifies the
- particular user in such a way that two different users may readily be
- distinguished. In the standard there are no restrictions on what may be
- included. The initiator identity is encoded as an ASN.1 [ISO 25] variable
- length graphic string with characters from the ISO646 set [ISO 9]. These names
- are normally inserted as needed by end systems, and this profile makes no
- provision for registration. The content is system-dependent.
-
- 5.3.2 MHS and Message User Interface Identification
-
- The MHS Recommendations [CCITT 2-9] identify a user to a Message Transfer
- Agent by means of a parameter called the Originator/Recipient Name (O/R Name).
-
- 32
-
-
-
-
-
-
-
- The O/R Name is encoded as a set of attributes describing the originator and
- receiver of the message. The attributes which must be supported by all
- implementations are the country name, the administration name, private domain
- name, organization name, organizational units, and personal name. The
- administration name attribute shall contain one blank when the originator
- and/or recipient are attached only to a private domain. The private domain
- name attribute must also be supported by all implementations, and be included
- when the originator and/or the recipients are located within different private
- domains. This information is summarized in Table 5.3.
-
-
-
-
-
-
- ZDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD?
- 3 Attribute Maximum ASCII Character Length 3
- 3 3
- 3 country name 3 3
- 3 administration name 16 3
- 3 private domain name 16 3
- 3 organization name 64 3
- 3 sequence of org. units 32 each 3
- 3 personal name 64 3
- @DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDY
- Table 5.3 Required O/R Name Attributes
-
- Private messaging systems within the government shall be capable of routing on
- the administration name, private domain name, organization name and
- organizational unit attributes taken in their hierarchical order. They shall
- also be capable of routing on or delivering based on the personal name
- attribute; that is, they shall act as Class 2 or Class 3 MTAs as defined in
- section 7.7.3.3 of the Workshop Agreements. The General Services
- Administration (GSA) shall be the Address Registration Authority for
- organization names. GSA shall delegate Address Registration Authority to the
- organization indicated by the organization name to assign organization unit
- and personal names. In assigning the organizational unit personal name space,
- the Address Registration Authorities shall follow the same rules stated
- earlier for NSAP addresses, except that organizational unit and personal names
- are not registered with GSA. Typically, a unique personal name is a surname
- or surname followed by given name, but it could also be an identifier of a
- particular office within the organization unit.
-
- CCITT assigns country name and administration name to public message service
- providers. Administrations assign private domain names to private messaging
- systems that wish to interoperate across the administration. The
- administration may also provide a registration service for government assigned
- organization names that wish to interoperate across or between administrative
- domains. A method for assigning private domain names in the absence of an
- administrative name is given in section 8.4.2 of Version 2.0 of the GOSIP
- User's Guide.
-
-
- 33
-
-
-
-
-
-
-
- 6. SECURITY OPTIONS
-
-
- Security is of fundamental importance to the acceptance and use of open
- systems in the U.S. Government. Part 2 of the Open Systems Interconnection
- reference model (Security Architecture) is now an International Standard (IS
- 7498/2). The standard describes a general architecture for security in OSI,
- defines a set of security services that may be supported within the OSI model,
- and outlines a number of mechanisms than can be used in providing the
- services. However, no protocols, formats or minimum requirements are
- contained in the standard.
-
- The text below describes one security option that may be optionally specified
- when security services are incorporated in the OSI network layer. This
- chapter does not describe at this time a complete set of security options that
- a user might desire nor a description of the security services and protocols
- that are associated with the specified parameter. It is a parameter that has
- been identified as being needed if certain security services (e.g.,
- confidentiality, access control) are incorporated in the network layer. The
- parameter should be used where required, but this chapter should be considered
- as a placeholder for future security specifications. Appendix 1 provides
- further information on what specifications are considered needed for OSI
- security.
-
- As defined by ISO, security features are considered both implementation and
- usage options. An organization desiring security in a product that is being
- purchased in accordance with this profile must specify the security services
- required, the placement of the services within the OSI architecture, the
- mechanisms to provide the services and the management features required. An
- acquisition authority desiring Connectionless Network Protocol (CLNP) security
- should specify the following described security option(s). When specifying
- the CLNP security option, the acquisition authority must ensure that all
- necessary Security Format Codes are provided.
-
- 6.1 REASON FOR DISCARD PARAMETERS
-
- The implementation of the security option requires assigning new parameter
- values to the Reason for Discard parameter in the CLNP Error Report PDU. The
- first octet of the parameter value contains an error type code as described in
- IS 8473. Values beyond those assigned in the standard are shown in Table 6.1.
- The second octet of the Reason for Discard parameter value either locates the
- error in the discarded PDU or contains the value zero as described in the
- standard.
-
-
- ZDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDBDDDDDDDDDDDDDDDBDDDDDDDDDDDDDDDDDDDDD?
- 3 Parameter Values 3 3 3
- CDDDDDDDDDDDDDDDDDBDDDDDDDDDDDDDDDDDDD4 3 3
- 3 Octet 1 3 Octet 2 3 Class of 3 Meaning 3
- 3Bits 8765 4321 3 Bits 8765 4321 3 Error 3 3
- 3 3 3 3 3
- CDDDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDDDD3
-
- 34
-
-
-
-
-
-
-
- 3 1101 0000 3 Discarded PDU 3 Security 3 Security Option 3
- 3 3 Offset or Zero 3 3 Out-of-Range 3
- 3 3 3 3 3
- 3 1101 1010 3 0000 0000 3 Security 3 Basic Portion 3
- 3 3 3 3 Missing 3
- 3 3 3 3 3
- 3 1101 1101 3 0000 0000 3 Security 3 Extended Portion 3
- 3 3 3 3 Missing 3
- 3 3 3 3 3
- 3 1101 0010 3 0000 0000 3 Security 3 Communication 3
- 3 3 3 3 Administratively 3
- 3 3 3 3 Prohibited 3
- 3 3 3 3 3
- @DDDDDDDDDDDDDDDDDADDDDDDDDDDDDDDDDDDDADDDDDDDDDDDDDDDADDDDDDDDDDDDDDDDDDDDDY
- Table 6.1 Extended Values in the Reason For Discard
- Parameter
-
- 6.2 SECURITY PARAMETER FORMAT
-
- IS 8473 defines the format of the CLNP security parameter. This parameter
- consists of the three fields shown in Table 6.2.
-
- Bits 8765 4321
- ZDDDDDDDDDDDDDDBDDDDDDDDDDDDDDDD?
- 3 Octets 3 3
- 3 3 1100 0101 3 Parameter Code
- 3 N 3 3
- CDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDD4
- 3 3 3
- 3 N + 1 3 Len = M 3 Parameter Length
- 3 3 3
- CDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDD4
- 3 N + 2 3 3
- 3 3 3 Parameter Value
- 3 N + M + 1 3 3
- @DDDDDDDDDDDDDDADDDDDDDDDDDDDDDDY
-
- Table 6.2 Security Parameter Format
-
- 6.2.1 Parameter Code
-
- IS 8473 assigns the value "1100 0101" to the Parameter Code field to identify
- the parameter as the Security Option.
-
- 6.2.2 Parameter Length
-
- This octet indicates the length, in octets, of the Parameter Value field.
-
- 6.2.3 Parameter Value
-
- The Parameter Value field contains the security information. IS 8473 defines
- only the first octet of the Parameter Value field. This section completes the
-
- 35
-
-
-
-
-
-
-
- definition of this field. Table 6.3 illustrates the format of the Parameter
- Value field within the Security Parameter.
-
-
- Bits 8765 4321
- ZDDDDDDDDDDDDBDDDDDDDDDDDDDDDDDD?
- 3 Octets 3 3
- 3N 3 1100 0101 3 Parameter Code
- CDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDD4
- 3 3 3
- 3N+1 3 Len = B + E + 1 3 Parameter Length
- 3 3 3
- CDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
- 3 3 3 3
- 3N+2 3 XX00 0000 3 Security Format Code 3
- 3 3 3 3
- CDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDD4 3
- 3N+3 3 3 Parameter
- 3 3 3 Basic Portion (Optional) Value
- 3N+B+2 3 3 3
- CDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDD4 3
- 3N+B+3 3 3 3
- 3 3 3 Extended Portion (Optional) 3
- 3N+B+E+2 3 3 3
- @DDDDDDDDDDDDADDDDDDDDDDDDDDDDDDADDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
-
- Table 6.3 Format - Parameter Value Field
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 36
-
-
-
-
-
-
-
- 6.2.3.1 Security Format Code
-
- As described in IS 8473, the high order two bits of the first octet of the
- Parameter Value field specify the Security Format Code. The standard reserves
- the remaining six bits and specifies that they must be zero.
-
- 6.2.3.2 Basic Portion
-
- The Basic Portion of the Security Option identifies the U.S. classification
- level to which a PDU is to be protected and the authorities whose protection
- rules apply to that PDU. This portion is optional and appears at most once in
- a PDU. When the Basic Portion appears in the Security Option of a PDU, it
- must be the first portion in the Parameter Value field of the Security
- Parameter. Paragraph 6.3 defines the format of the Basic Portion.
-
- 6.2.3.3 Extended Portion
-
- The Extended Portion permits additional security labelling information, beyond
- that present in the Basic Portion, to be supplied in a CLNP PDU to meet the
- needs of registered authorities. This portion is optional and appears at most
- once in a PDU. The Extended Portion must follow the Basic Portion, if
- present, in the Parameter Value field of the CLNP Security Parameter. In
- addition, if this portion is required by an authority for a specific system,
- it must be specified explicitly in any Request for Proposal for that system.
- Paragraph 6.4 defines the format of the Extended Portion.
-
- 6.3 BASIC PORTION OF THE SECURITY OPTION
-
- The Basic Portion is used by the components of an internetwork to:
-
- A. Transmit from source to destination, in a network standard
- representation, the common security labels required by computer security
- models.
-
- B. Validate the PDU as appropriate for transmission from the source and
- delivery to the destination.
- C. Ensure that the route taken by the PDU is protected to the level
- required by all protection authorities indicated on the PDU.
-
- Table 6.4 shows the format of the Basic Portion of the Security Option.
-
- Bits 8765 4321
- ZDDDDDDDDDDDDDDDBDDDDDDDDDDDDDDDDDDD?
- 3 Octets 3 3
- 3 N 3 1000 0010 3 Basic Type Indicator
- 3 3 3
- CDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDD4
- 3 3 3
- 3 N+1 3 Len = I 3 Length of Basic Information
- 3 3 3
- CDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDD4
- 3 3 3
-
- 37
-
-
-
-
-
-
-
- 3 N+2 3 3
- 3 3 3 Basic Information
- 3 N+I+1 3 3
- @DDDDDDDDDDDDDDDADDDDDDDDDDDDDDDDDDDY
-
- Table 6.4 Format - Basic Portion
- 6.3.1 Basic Type Indicator
-
- The value of this field identifies this as the Basic Portion of the Security
- Option.
-
-
- 6.3.2 Length of Basic Information
-
- This length field, when present, indicates the length, in octets, of the Basic
- Information field. The Basic Information field is variable in length and has
- a minimum length of two octets.
-
- 6.3.3 Basic Information
-
- The Basic Information field consists of two subfields as Table 6.5
- illustrates.
-
-
- Bits 8765 4321
- ZDDDDDDDDDDDDDBDDDDDDDDDDDDDDDDD?
- 3Octets 3 3
- 3 B 3 1000 0010 3 Basic Type Indicator
- 3 3 3
- CDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDD4
- 3 3 3
- 3 B + 1 3 Len = F + 1 3 Length of Basic Information
- 3 3 3 (Minimum = 2 Octets)
- CDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
- 3 3 3 3
- 3 B + 2 3 3 Classification Level 3
- 3 3 3 3
- CDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDD4 Basic
- 3 3 3 Information
- 3B + 3 3 3 3
- 3 3 3 Protection Authority Flags 3
- 3B + F + 2 3 3 3
- @DDDDDDDDDDDDDADDDDDDDDDDDDDDDDDADDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
- Table 6.5 Format - Basic Information Field
-
- 6.3.3.1 Classification Level
-
- The Classification Level field specifies the U.S. classification level to
- which the PDU must be protected. The information in the PDU must be treated
- at this level unless it is regraded in accordance under the procedures of all
- the authorities identified by the Protection Authority Flags. The field is
- one octet in length. Table 6.6 provides the encodings for this field.
-
- 38
-
-
-
-
-
-
-
-
- ZDDDDDDDDDDDDDDDDDDDDDBDDDDDDDDDDDDDDDDDDDD?
- 3 VALUE 3 LEVEL 3
- 3 Bits 8765 4321 3 3
- CDDDDDDDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDDD4
- 3 0000 0001 3 RESERVED 4 3
- 3 0011 1101 3 TOP SECRET 3
- 3 0101 1010 3 SECRET 3
- 3 1001 0110 3 CONFIDENTIAL 3
- 3 0110 0110 3 RESERVED 3 3
- 3 1100 1100 3 RESERVED 2 3
- 3 1010 1011 3 UNCLASSIFIED 3
- 3 1111 0001 3 RESERVED 1 3
- @DDDDDDDDDDDDDDDDDDDDDADDDDDDDDDDDDDDDDDDDDY
- Table 6.6 Classification Levels
-
- 6.3.3.2 Protection Authority Flags
-
- The Protection Authority Flags field indicates the National Access Program(s)
- or Special Access Program(s) whose rules apply to the protection of the PDU.
- Its field length and source flags are described below. To maintain the
- architectural consistency and interoperability of DoD common user data
- networks, users of these networks should submit requirements for additional
- Protection Authority Flags to DCA DISDB, Washington, D. C. 20305-2000 for
- review and approval.
-
- A. Field Length: The Protection Authority Flags field is variable in
- length. The low order bit (Bit 1) of an octet is encoded as "0" if
- the octet is the final octet in the field. If there are additional
- octets, then the low order bit is encoded as "1". Currently, there
- are less than eight authorities. Therefore, only one octet is
- required and the low order bit of this octet is encoded as "0".
-
- B. Source Flags: Bits 2 through 8 in each octet are flags. Each
- flag is associated with an authority as indicated in Table 6.7. The
- bit corresponding to an authority is "1" if the PDU is to be protected
- in accordance with the rules of that authority.
-
- ZDDDDDDDDDDDBDDDDDDDDDDDDDDDDDDBDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD?
- 3 Bit 3 3 3
- 3 Number 3 Authority 3 Point of Contact 3
- CDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD4
- 3 3 3 3
- 3 8 3GENSER 3 Designated Approving Authority 3
- 3 3 3 per DoD 5200.28 3
- 3 3 3 3
- 3 7 3SIOP-ESI 3 Department of Defense 3
- 3 3 3 Organization of the 3
- 3 3 3 Joint Chiefs of Staff 3
- 3 3 3 Attn: J6T 3
- 3 3 3 Washington, D.C. 3
- 3 3 3 3
-
- 39
-
-
-
-
-
-
-
- 3 6 3 SCI 3 Director of Central Intelligence 3
- 3 3 3 Attn: Chairman, Information Handling Committee 3
- 3 3 3 Intelligence Community Staff 3
- 3 3 3 Washington, D. C. 20505 3
- 3 3 3 3
- 3 5 3 NSA 3 National Security Agency 3
- 3 3 3 9800 Savage Road 3
- 3 3 3 Attn: TO3 3
- 3 3 3 Ft. Meade, MD 20755-6000 3
- 3 3 3 3
- 3 4 3 DOE 3 Department of Energy 3
- 3 3 3 Attn: DP343.2 3
- 3 3 3 Washington, D.C. 20545 3
- 3 3 3 3
- 3 3 , 2 3 Unassigned 3 3
- 3 3 3 3
- 3 1 3 Extension Bit 3 Presently always "O" 3
- @DDDDDDDDDDDADDDDDDDDDDDDDDDDDDADDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDY
- Table 6.7 Protection Authority Bit Assignments
-
-
- 6.4 EXTENDED PORTION OF THE SECURITY OPTION
-
- Table 6.8 illustrates the format for the Extended Portion. To maintain the
- architectural consistency of DoD common user data networks, and to maximize
- interoperability, users of these networks should submit their plans for the
- use of the Extended Portion of the Security Option to DCA DISDB, Washington,
- D.C. 20305-2000 for review and approval. Once approved, DCA DISDB will assign
- Additional Security Information Format Codes to the requesting activities.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 40
-
-
-
-
-
-
-
- Bits 8765 4321
- ZDDDDDDDDDDDDDBDDDDDDDDDDDDDDDDD?
- 3 Octets 3 3
- 3 N 3 1000 0101 3 Extended Type Indicator
- CDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDD4
- 3 3 3
- 3 N+1 3 Len = I 3 Length of Extended Information
- 3 3 3
- CDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDD4
- 3 N+2 3 3
- 3 3 3 Extended Information
- 3 N+I+1 3 3
- @DDDDDDDDDDDDDADDDDDDDDDDDDDDDDDY
- Table 6.8 Format - Extended Portion
-
- 6.4.1 Extended Type Indicator
-
- The value of this field identifies this as the Extended Portion of the
- Security Option.
-
- 6.4.2 Length of Extended Information
-
- This length field indicates the length, in octets, of the Extended Information
- field. The Extended Information field is variable in length with a minimum
- length of two octets.
-
- 6.4.3 Extended Information
-
- The Extended Information field consists of three subfields as Table 6.9
- illustrates. These three fields form a sequence. This sequence may appear
- multiple times, forming a set, within the Extended Information field.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 41
-
-
-
-
-
-
-
-
- Bits 8765 4321
- ZDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD?
- 3 Octets 3
- 3 E 1000 0101 3 Extended Type Indicator
- CDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD4
- 3 E+1 Len = (B - A) + 1 3 Length of Extended
- Information
- 3 3 (Minimum = 2 Octets)
-
- CDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDEDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
- DDDDDDDDD?
- 3 3
- 3
- A 3 E+2 3 Additional Security
- Information Format Code 3
- 3 3
- 3
- CDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD4
- 3
- 3 3
- 3
- 3 E+3 Len = I 3 Length of Additional Security
- Information 3
- 3 3
- 3
- CDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD4
- 3
- 3 3
- 3
- 3 E+4 3
- 3
- 3 3 Additional Security
- Information 3
- 3 E+I+3 3 (Zero or more octets)
- 3
- @DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDY
- 3
- . .
- 3
- . (Additional Sequences .
- Extended
- . of the above three fields) .
- Information
- . .
- 3
- ZDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD?
- 3
- 3 E+N 3 Additional Security
- Information Format Code 3
- CDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD4
- 3
-
- 42
-
-
-
-
-
-
-
- 3 3
- 3
- 3 E+N+1 Len = J 3 Length of Additional Security
- Information 3
- 3 3
- 3
- CDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD4
- 3
- 3 E+N+2 3
- 3
- 3 3 Additional Security
- Information 3
- B 3 E+N+J+1 3 (Zero or more octets)
- 3
-
- @DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDADDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
- DDDDDDDDDY
- Table 6.9 Format - Extended Information Field
-
- 6.4.3.1 Additional Security Information Format Code
-
- The value of the Additional Security Information Format Code corresponds to a
- particular format and meaning for a specific Additional Security Information
- field. Each format code is assigned to a specific controlling activity.
- Once assigned, this activity becomes the authority for the definition of the
- remainder of the Additional Security Information identified by that format
- code. A single controlling activity may be responsible for multiple format
- codes. However, a particular format code may appear at most once in a PDU.
- For each Additional Security Information Format Code an authority is
- responsible for, that authority will provide sufficient criteria for
- determining whether a CLNP PDU marked with its Format Code should be accepted
- or rejected. Whenever possible, this criteria will be Unclassified.
-
- Note: The bit assignments for the Protection Authority flags of the Basic
- Portion of the Security Option have no relationship to the "Additional
- Security Information Format Code" of this portion.
-
- 6.4.3.2 Length of Additional Security Information
-
- This field provides the length, in octets, of the "Additional Security
- Information" field immediately following.
-
- 6.4.3.3 Additional Security Information
-
- The Additional Security Information field contains the additional security
- relevant information specified by the authority identified by the "Additional
- Security Information Format Code." The format, length, content, and semantics
- of this field are determined by that authority. The minimum length of this
- field
- is zero.
-
- 6.5 USAGE GUIDELINES
-
- 43
-
-
-
-
-
-
-
-
- A PDU is "within the range" if
-
- MIN-LEVEL <= PDU-LEVEL <= MAX-LEVEL
-
- where MIN-LEVEL and MAX-LEVEL are the minimum and maximum security
- levels, respectively, that the system is accredited for. The term PDU-LEVEL
- refers to the security level of the PDU. In this context, the "security
- level" may involve the combination of three factors:
-
- 1) classification level
- 2) protection authorities
- 3) additional security labelling information as required and defined by
- the responsible activity.
-
- The authorities responsible for accrediting a system or collection of systems
- are also responsible for determining whether and how these factors interact to
- form a security level or security range. A PDU should be accepted for further
- processing only if it is within range. Otherwise, the Out-of-Range procedure
- described in Paragraph 6.6 should be followed.
-
- 6.5.1 Basic Portion of the Security Option
-
- Use of the information contained in the Basic Portion of the Security Option
- requires that an end system be aware of:
-
- A. the classification level, or levels, at which it is permitted to
- operate, and
-
- B. the protection authorities responsible for its accreditation.
-
- Representation of this configuration information is implementation dependent.
-
- 6.5.2 Extended Portion of the Security Option
-
- Use of the Extended Portion of the Security Option requires that the end
- system configuration accurately reflects the accredited security parameters
- associated with communication via each network interface. Representation of
- the security parameters and their binding to specific network interfaces is
- implementation dependent.
-
- 6.6 OUT-OF-RANGE PROCEDURE
-
- If the Out-Of-Range condition was triggered by:
-
- A. A required, but missing, Security Option or Basic or Extended
- Portion of a Security Option, then the PDU should be discarded. In
- addition, a CLNP Error Report or other form of reply is not permitted
- in this case. However, a local security policy may permit data to be
- delivered or a CLNP Error Report PDU to be processed provided a reply
- is not sent.
-
-
- 44
-
-
-
-
-
-
-
- B. A PDU whose security level is less than the end system's minimum
- security level, then the PDU should be discarded. In addition, a CLNP
- Error Report or other form of reply is not permitted in this case.
- However, local security policy may permit data to be delivered or a
- CLNP Error Report PDU to be processed provided a reply is not sent.
-
- C. A PDU whose security level is greater than the end system's
- maximum security level, then:
-
- 1. If a CLNP Error Report PDU triggered the Out-of-Range condition,
- then no reply is permitted and the PDU should be discarded. A CLNP Error
- Report PDU must not be sent in this case.
-
- 2. Otherwise, discard the PDU and send a CLNP Error Report PDU to the
- originating CLNP entity. The first octet of the Reason for Discard
- parameter is set as specified in Table 6.1. The second octet of the
- Reason for Discard parameter identifies the Out-of-Range portion of the
- Security Option. It should point to the first octet (i.e., the type
- indicator) of the Out-of-Range portion. Alternatively, the second octet
- can be set to zero. The response is sent at the maximum classification
- level of the end system which received the PDU. The protection authority
- flags are set to be the intersection of those for which the host is
- accredited and those present in the PDU which triggered this response.
-
- Example: PDU = "Secret, GENSER"
- End System Level = "Unclassified, GENSER".
- Reply = "Unclassified, GENSER".
-
- These are the least restrictive actions permitted by this protocol.
- Individual end systems, system administrators, or protection authorities may
- impose more stringent restrictions on responses and in some instances may not
- permit any response at all to a PDU which is outside the accredited security
- range of an end system.
-
- 6.7 TRUSTED INTERMEDIARY PROCEDURE
-
- Certain devices in an internetwork may act as intermediaries to validate that
- communications between two end systems is authorized. This decision is based
- on a combination of knowledge of the end systems and the values in the CLNP
- Security Option. [The Blacker Front End (BFE) is one example of such a
- trusted device.] These devices may receive CLNP PDUs which are in range for
- the intermediate device, but are either not within the accredited range for
- the source or the destination. In the former case, the PDU should be treated
- as described in Paragraph 6.6. In the latter case, a CLNP Error Report PDU
- should be sent to the originating CLNP entity. The first octet of the Reason
- for Discard parameter should be set to 1101 0010. This code indicates to the
- originating CLNP entity that communication with the end system is
- administratively prohibited (refer to Table 6.1). The security range of the
- interface on which the reply will be sent determines whether a reply is
- allowed and at what security level it should be sent.
-
-
-
- 45
-
-
-
-
-
-
-
- REFERENCES
-
-
- National Institute of Standards and Technology
-
- 1. NIST Special Publication 500-177, Stable Implementation Agreements
- for Open Systems Interconnection Protocols, Version 3. This document can be
- purchased from National Technical Information Service (NTIS), U. S. Department
- of Commerce, 5285 Port Royal Road, Springfield, VA 22161. For telephone
- orders call: (703) 487-4650. This document may also be purchased from the
- IEEE Computer Society, Order Department, phone: 1-800-272-6657.
-
- 2. FIPS l07, Local Area Networks: Baseband Carrier Sense Multiple
- Access with Collision Detection Access Method and Physical Layer
- Specifications and Link Layer Protocol, NTIS, U.S. Department of Commerce,
- 5285 Port Royal Road, Springfield, VA 22l6l.
-
- 3. FIPS l00, Interface Between Data Terminal Equipment (DTE) and Data
- Circuit-Terminating Equipment (DCE) For Operation With Packet-Switched Data
- Communications Networks, NTIS, U.S. Department of Commerce, 5285 Port Royal
- Road, Springfield, VA 22l6l.
-
- 4. Implementation Agreements Among Participants of OSINET, NBSIR 89-
- 4158, National Institute of Standards and Technology.
-
- 5. Military Supplement to ISO Transport Protocol, National Institute of
- Standards and Technology, National Computer Systems Laboratory, ICST/SNA-85-
- 17, 1985.
-
- 6. Implementation Guide for ISO Transport Protocol, National Institute
- of Standards and Technology, National Computer Systems Laboratory, ICST/SNA-
- 85-18, 1985.
-
- 7. NIST Special Publication 500-163 Government Open Systems
- Interconnection User's Guide. This document can be purchased from the
- National Technical Information Service (NTIS), U. S. Department of Commerce,
- 5285 Port Royal Road, Springfield, VA 22161. For telephone orders call (7023)
- 487-4650. The NTIS order number is PB90-111212.
-
- 8. GOSIP Conformance and Interoperation Testing and Registration,
- NCSL/SNA 90-2, 1990.
-
- 9. NIST Special Publication 500-182, Message Handling Systems
- Implementation Evaluation Guidelines. See [NIST 7] for NTIS ordering
- information.
-
- National Communications System
-
- Federal Standard FED-STD 1041, Interface Between Data Terminal Equipment (DTE)
- and Data Circuit-Terminating Equipment (DCE) For Operation With Packet-
- Switched Data Communications Networks, National Communications System.
-
-
- 46
-
-
-
-
-
-
-
- Institute of Electrical and Electronic Engineers, Inc.
-
- Binary Floating Point Arithmetic (ANS1 Approved), IEEE 754, March 21, 1985,
- Institute of Electrical and Electronics Engineers.
-
- The above document may be obtained from: IEEE Standards Office, 345 East 47th
- Street, New York, N.Y. l00l7.
-
- Electronic Industries Association
-
- Interface between Data Terminal Equipment and Data Communication Equipment
- Employing Serial Binary Data Interchange, EIA-232C.
- American National Standards Institute
-
- 1. Integrated Services Digital Network - Basic Access Interface for Use
- on Metallic Loops for Application on the Network Side of the NT-Layer 1
- Specification, ANS T1.601-1988.
-
- 2. Integrated Services Digital Network - Basic Access Interface at S and
- T Reference Points - Layer 1 Specification, ANS T1.605-1988.
-
- 3. Carrier to Customer Installation - DS1 Metallic Interface, ANS T1.
- 403-1989.
-
- International Organization for Standardization
-
- 1. Information Processing Systems - Open Systems Interconnection - Basic
- Reference Model, Ref. No. ISO 7498-1984(E).
-
- 2. Information Processing Systems - Data Communications - Use of X.25 to
- provide the OSI Connection Mode Network Service, IS 8878.
-
- 3. Information Processing Systems - Open Systems Interconnection -
- Network Service Definition, IS 8348.
-
- 4. Information Processing Systems - Open Systems Interconnection -
- Addendum to the Network Service Definition Covering Connectionless Data
- Transmission, ISO 8348 Addendum 1.
-
- 5. Information Processing Systems - Open Systems Interconnection -
- Addendum to the Network Service Definition Covering Network Layer Addressing,
- ISO 8348 Addendum 2.
-
- 6. Information Processing Systems - Open Systems Interconnection -
- Internal Organization of the Network Layer, DIS 8648, N3985, Feb., 1986.
-
- 7. Information Processing Systems - Open Systems Interconnection -
- Protocol for Providing the Connectionless Network Service, IS 8473, N3998,
- March, 1986.
-
- 8. Information Processing Systems - Open Systems Interconnection - Data
- Communication - X.25 Packet Level Protocol for Data Terminal Equipment, ISO
-
- 47
-
-
-
-
-
-
-
- 8208.
-
- 9. 7-bit Coded Character Set for Information Processing Interchange, ISO
- 646, l973.
-
- 10. Information Interchange -- Representation of Local Time
- Differentials, ISO 3307, l975.
-
- 11. Information Processing Systems - Open Systems Interconnection -
- Working Draft - End System to Intermediate System Routing Exchange Protocol
- for use in Conjunction with ISO 8473.
-
- 12. Information Processing Systems - Open Systems Interconnection -
- Transport Service Definition, ISO 8072, l984.
-
- 13. Information Processing Systems - Open Systems Interconnection -
- Transport Protocol Specification, ISO 8073, l984.
-
- 14. Information Processing Systems - Open Systems Interconnection -
- Session Service Definition, ISO 8326, l987(E).
-
- 15. Information Processing Systems - Open Systems Interconnection -
- Session Protocol Specification, ISO 8327, l987(E).
-
- 16. Information Processing Systems - Open Systems Interconnection - File
- Transfer, Access and Management Part 1: General Introduction, ISO 8571-1.
-
- 17. Information Processing Systems - Open Systems Interconnection - File
- Transfer, Access and Management Part 2: The Virtual Filestore Definition, ISO
- 8571-2.
-
- 18. Information Processing Systems - Open Systems Interconnection - File
- Transfer, Access and Management Part 3: File Service Definition, ISO 8571-3.
-
-
- 19. Information Processing Systems - Open Systems Interconnection - File
- Transfer, Access and Management Part 4: File Protocol Specification, ISO
- 8571-4.
-
- 20. Information Processing Systems - Open Systems Interconnection -
- Connection-Oriented Presentation Service Definition, ISO 8822.
-
- 21. Information Processing Systems - Open Systems Interconnection -
- Connection-Oriented Presentation Protocol Specification, ISO 8823.
-
- 22. Information Processing Systems - Open Systems Interconnection -
- Service Definition for Association Control Service Element - Part 2:
- Association Control, ISO 8649.
-
- 23. Information Processing Systems - Open Systems Interconnection -
- Protocol Specification for Association Control Service Element: Association
- Control, ISO 8650.
-
- 48
-
-
-
-
-
-
-
-
- 24. Information Processing Systems - Open Systems Interconnection -
- Specification of Abstract Syntax Notation One (ASN.1), ISO 8824.
-
- 25. Information Processing Systems - Open Systems Interconnection -
- Specification of Basic Encoding Rules for Abstract Syntax Notation One
- (ASN.1), ISO 8825.
-
- 26. Information Processing Systems - Data Communications - High-Level
- Data Link Control Procedures - Description of the X.25 LAPB-compatible DTE
- Data Link Procedures, ISO 7776.
-
- 27. Information Processing Systems - Data Interchange - Structures for
- the Identification of Organizations, ISO 6523, 1984.
-
- 28. Information Processing Systems - Local Area Networks - Part 2:
- Logical
- Link Control, DIS 8802/2.
-
- 29. Information Processing Systems - Local Area Networks - Part 3:
- Carrier Sense Multiple Access With Collision Detection, ISO 8802/3
-
- 30. Information Processing Systems - Local Area Networks - Part 4: Token-
- passing Bus Success Method and Physical Layer Specifications, ISO 8802/4.
-
- 3l. Information Processing Systems - Local Area Networks Part 5: Token
- Ring Access Method and Physical Layer Specifications, ISO 8802/5.
-
- 32. Information Processing Systems - Open Systems Interconnection -
- Virtual Terminal Services - Basic Class, ISO 9040.
-
- 33. Information Processing Systems - Open Systems Interconnection -
- Virtual Terminal Protocol - Basic Class, ISO 9041.
-
- 34. Information Processing Systems - Open Systems Interconnection.
- Virtual Terminal Service, Basic Class, ISO 9040, Addendum 1, 1988.
-
- 35. Information Processing Systems - Open Systems Interconnection,
- Virtual Terminal Protocol, Basic Class, ISO 9041, Addendum 1, 1988.
-
- 36. Information Processing - Text and Office Systems-Office-Document
- Architecture (ODA) and Interchange Format - Part 1: Introduction and General
- Principles, ISO 8613-1, 1988.
-
- 37. Information Processing - Text and Office Systems-Office-Document
- Architecture (ODA) and Interchange Format - Part 2: Document Structures ISO
- 8613-2, 1988.
-
- 38. Information Processing - Text and Office Systems-Office-Document
- Architecture (ODA) and Interchange Format - Part 4: Document Profile, ISO
- 8613-4, 1988.
-
-
- 49
-
-
-
-
-
-
-
- 39. Information Processing - Text and Office Systems-Office-Document
- Architecture (ODA) and Interchange Format - Part 5: Office Document
- Interchange Format (ODIF), ISO 8613-5, 1988.
-
- 40. Information Processing - Text and Office Systems-Office-Document
- Architecture (ODA) and Interchange Format - Part 6: Character Content
- Architectures, ISO 8613-6, 1988.
-
- 41. Information Processing - Text and Office Systems-Office-Document
- Architecture (ODA) and Interchange Format - Part 7: Raster Graphics Content
- Architectures, ISO 8613-7, 1988.
-
- 42. Information Processing - Text and Office Systems-Office-Document
- Architecture (ODA) and Interchange Format - Part 8: Geometric Graphics Content
- Architectures, ISO 8613-8, 1988.
-
- 43. Information Processing Systems - Protocol Identification in the
- Network Layer, DTR 9577.
-
- 44. Information Processing Systems - End System to Intermediate System
- Routing Exchange Protocol for use with ISO 8473, IS 9542.
-
- 45. Information Processing Systems - Data Communications - Provision of
- the OSI Connection-mode Network Service, by Packet Mode Terminal Equipment
- connected to an Integrated Services Digital Network (ISDN), DIS 9574.
-
- 46. Information Processing Systems - Transport Service Definition
- covering Connectionless Mode Transmission, ISO 8072/ADD.
-
- 47. Information Processing Systems - Protocol for Providing the
- Connectionless Mode Transport Service, ISO 8602.
-
- 48. Information Processing Systems - Telecommunications and information
- exchange between systems - OSI Routing Framework, ISO/TR 9575.
-
- 49. Information Processing Systems Telecommunications and information
- exchange between systems - Intermediate systems to Intermediate system Intra-
- Domain routing exchange protocol for use in conjunction with the protocol for
- providing the Connectionless mode Network Service ISO/IEC JTC1/SC6 DP 10589.
-
- The above documents may be obtained from:
-
- ANSI Sales Department
- 1430 Broadway
- New York, NY 10018
- (212) 642-4900
-
- International Telephone and Telegraph Consultative Committee
-
- 1. CCITT Recommendation X.25-1984, Interface Between Data Terminal
- Equipment (DTE) and Data Circuit-Terminating Equipment (DCE) for Terminals
- Operating in the Packet Mode on Public Data Networks.
-
- 50
-
-
-
-
-
-
-
-
- 2. CCITT Recommendation X.400, (Red Book, 1984), Message Handling
- Systems: System Model-Service Elements.
-
- 3. CCITT Recommendation X.40l, (Red Book, 1984), Message Handling
- Systems: Basic Service Elements and Optional User Facilities.
-
- 4. CCITT Recommendation X.408, (Red Book, 1984), Message Handling
- Systems: Encoded Information Type Conversion Rules.
-
- 5. CCITT Recommendation X.409, (Red Book, 1984), Message Handling
- Systems: Presentation Transfer Syntax and Notation.
-
- 6. CCITT Recommendation X.4l0, (Red Book, 1984), Message Handling
- Systems: Remote Operations and Reliable Transfer Server.
-
- 7. CCITT Recommendation X.4ll, (Red Book, 1984), Message Handling
- Systems: Message Transfer Layer.
-
- 8. CCITT Recommendation X.420, (Red Book, 1984), Message Handling
- Systems: Interpersonal Messaging User Agent Layer.
-
- 9. CCITT Recommendation X.430, (Red Book, 1984), Message Handling
- Systems: Access Protocol for Teletex Terminals.
-
- 10. CCITT Recommendation X.214, (Red Book, 1984), Transport Service
- Definition for Open Systems Interconnection for CCITT Applications.
-
- 11. CCITT Recommendation X.224, (Red Book, 1984), Transport Protocol
- Specification for Open Systems Interconnection for CCITT Applications.
-
- 12. CCITT Recommendation X.215 (Red Book, 1984), Session Service
- Definition for Open Systems Interconnection for CCITT Applications.
-
- 13. CCITT Recommendation X.225 (Red Book, 1984), Session Protocol
- Specification for Open Systems Interconnection for CCITT Applications.
-
- 14. CCITT Recommendation X.400 - Series Implementor's Guide (Version 6,
- November 1987).
-
- 15. CCITT Recommendation X.121 (Red Book, 1985), International
- Numbering Plan for Public Data Networks.
-
- 16. CCITT Recommendation V.35 - Data Transmission at 48 kilobits/second
- using 60-108 kHz group band circuits.
-
- 17. CCITT Recommendation T.410 (Blue Book, 1988) Open Document
- Architecture (ODA) and Interchange Format - Overview
-
- 18. CCITT Recommendation T.411 (Blue Book, 1988) Open Document
- Architecture (ODA) and Interchange Format - Introduction and General
- Principles
-
- 51
-
-
-
-
-
-
-
-
- 19. CCITT Recommendation T.412 (Blue Book, 1988) Open Document
- Architecture (ODA) and Interchange Format - Document Structures
-
- 20. CCITT Recommendation T.414 (Blue Book, 1988) Open Document
- Architecture (ODA) and Interchange Format - Document Profile
-
- 21. CCITT Recommendation T.415 (Blue Book, 1988) Open Document
- Architecture (ODA) and Interchange Format - Document Interchange Format (ODIF)
-
- 22. CCITT Recommendation T.416 (Blue Book, 1988) Open Document
- Architecture (ODA) and Interchange Format - Character Content Architectures
-
- 23. CCITT Recommendation T.417 (Blue Book, 1988) Open Document
- Architecture (ODA) and Interchange Format - Raster Graphics Content
- Architectures.
-
- 24. CCITT Recommendation T.418 (Blue Book, 1988) Open Document
- Architecture (ODA) and Interchange Format - Geometric Graphics Content
- Architectures.
-
- 25. CCITT Recommendation Q.921 (I.441) (Blue Book, 1988) ISDN User-
- Network Interface Data Link Layer Specification.
-
- 26. CCITT Recommendation Q.931 (I.451) (Blue Book, 1988) ISDN User-
- Network Interface Layer 3 Specification for Basic Call Control.
-
- 27. CCITT Recommendation X.31 (Blue Book, 1988) Support of Packet Mode
- Terminal Equipment by an ISDN.
-
- The above documents may be obtained from: International Telecommunications
- Union, Place des Nations, CH l2ll, Geneve 20 SWITZERLAND.
-
- Miscellaneous
-
- 1. Manufacturing Automation Protocol
-
- 2. Technical and Office Protocols, Specification Version 3.0
-
- For copies of the two documents listed above, contact: Corporation for Open
- Systems, 1750 Old Meadow Road, McLean, VA 22102-4306.
-
-
-
-
-
-
-
-
-
-
-
-
- 52
-
-
-
-
-
-
-
- FOREWORD TO THE APPENDICES
-
-
- Appendices 1-5 describe U. S. Government advanced requirements for which
- adequate specifications have yet to be developed. This section, revised by
- the GOSIP Advanced Requirements Group, gives an updated and more complete
- summary of protocols planned for inclusion in future versions of the document.
- Each summary states the requirements for including the protocol in GOSIP and a
- plan of work to meet those requirements.
-
- New versions of GOSIP will be issued no more frequently than once a year and
- the comments of manufacturers, government agencies and the public will be
- solicited before each new version is released.
-
- The following protocols are candidates for inclusion in Version 3 of GOSIP.
-
- 1. Directory Services
- 2. Optional Class 2 Transport Protocol
- 3. CGM
- 4. Virtual Terminal (X3, page, scroll profiles)
- 5. MHS extensions based on 1988 CCITT Recommendations
- 6. FTAM extensions
- 7. FDDI
- 8. Network Management (Also the subject of a separate FIPS.)
- 9. Optional Security Enhancements
- 10. SGML
- 11. Manufacturing Message Specification
- 12. Intra-domain Dynamic Routing
- 13. EDI
-
- The following protocols are candidates for inclusion in Version 4 of GOSIP.
-
- 1. Transaction Processing
- 2. Remote Database Access
- 3. Additional Optional Security Enhancements
- 4. Additional Network Management Functions
- 5. Inter-domain Dynamic Routing
-
- The purpose of Appendices 1-5 is to assist federal agencies in planning
- decisions relating to the acquisition of implementations of OSI protocols.
-
- Appendix 6 specifies a list of acronyms.
-
- These appendices are not part of the Federal Information Processing Standard.
-
-
-
-
-
-
-
-
-
- 53
-
-
-
-
-
-
-
- APPENDIX 1. SECURITY
-
-
- 1.1 BACKGROUND
-
- The Open Systems Interconnection Security Architecture is now an International
- Standard (IS 7498/2). This document provides a general architecture that may
- be used in implementing security services in OSI networks. Five primary
- security services are specified in the architecture as well as the OSI layers
- at which security services could be offered. The document also discusses many
- security mechanisms which can be used in providing the services.
-
- The OSI Security Architecture provides a basis for developing security but it
- does not provide specifications for implementing security. A significant
- level of effort is required before specifications for security are available
- that can be used in standards. This appendix addresses the need for security
- standards, the status of standards being developed and plans for developing
- additional required standards.
-
- While the term "Open Systems" implies that users of such systems intend that
- the systems be open to others, the users always want to provide access to such
- systems only to authorized users for authorized purposes. Systems that
- process sensitive and valuable data, especially classified data, must be
- protected from a wide variety of threats. Vulnerabilities of open systems
- include unauthorized access and denial of service. Vulnerabilities of data in
- open systems include unauthorized disclosure, modification and destruction,
- both accidentally and intentionally.
-
- Computer programs designed to obtain, modify or destroy data or to simply deny
- service to authorized users are a threat to networks of computers. Such a
- program is often called a Virus or a Worm. Computers which allow programs to
- be executed that have been imported from an external source, either via the
- network or through a storage medium, may be vulnerable to such programs.
- Users should always have back-up copies of valuable data in an off-line
- storage facility in case the on-line data is modified or destroyed. Trusted
- systems with isolation and controlled sharing mechanisms should be used to
- minimize the threat of a Virus or a Worm.
-
- Security is an option in GOSIP. As such, security services may be provided at
- one or more of the layers 2, 3, 4, 6 and 7. The Appendix 1 figure depicts
- placement of security in the overall profile by augmenting Figure 3.2 with
- optional security in order to form the Government OSI security architecture.
- The security architecture described here suggests a range of choices for
- security services and their placement. It is expected that a subset of these
- services and layers will adequately satisfy specific security requirements.
- Because security inherently restricts access and if applied at different
- layers will prohibit interoperability, it is the responsibility of an
- acquisition authority to insure that the security options chosen provide the
- desired interoperability as well as the required security.
-
- 1.2 REQUIREMENTS
-
-
- 54
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-
-
-
-
-
-
- The primary security services that are defined in the OSI security
- architecture are authentication, access control, confidentiality, integrity
- and non-repudiation. These are defined in detail in IS 7498/2 and are
- summarized, with simple examples given, below:
-
- *Data confidentiality services protect against unauthorized disclosure.
- Protecting the details of an attempted corporate takeover is an example of the
- need for confidentiality.
-
- *Data integrity services protect against unauthorized modification,
- insertion and deletion. Electronic funds transfer between banks requires
- protection against modification of the information.
-
- *Authentication services verify the identity of communicating peer entities
- and the source of data. Owners of bank accounts require assurance that money
- will be withdrawn only by the owner.
-
-
- *Access control services allow only authorized communication and system
- access. Only financial officers are authorized access to a company's
- financial plans.
-
- *Non-repudiation with proof of origin provides to the recipient proof of the
- origin of data and protects against any attempt by the originator to falsely
- deny sending the data or its contents. Non-repudiation with proof of origin
- can be used to prove to a judge that a person signed a contract.
-
- Requirements have been identified for government applications for all five of
- these services, especially the first four. Authentication, confidentiality
- and integrity services may be implemented in layers 3, 4 and 7 of the OSI
- architecture while access control and non-repudiation services are offered
- only at layer 7. Applications, such as Electronic Message Handling Systems,
- can be provided all security services at layer 7. Providing security at
- either layer 3 or 4 is generally required but not at both layers. The
- selection of security services at specific layers must be made by the
- acquisition authority and depend on the benefits derived and the costs
- encountered.
-
- 1.3 STATUS
-
- Interoperability standards are required for security at layers 2, 3, 4, and 7
- of the OSI architecture. Specifications for security at layers 3 and 4 as
- well as for Electronic Message Handling Systems have been prepared within the
- Secure Data Network System project. (See NISTIR 90-4250) Specifications for
- security at layer 2 are being drafted by the IEEE 802.10 LAN Security Working
- Group developing a Standard for Interoperable LAN Security (SILS).
- Specifications for authentication of data have been issued in standards by the
- National Institute of Standards and Technology (formerly the National Bureau
- of Standards) (FIPS 113) and ANSI (ANSI X9.9). Specifications for key
- management protocols have been issued in a standard by ANSI (X9.17).
-
- The OSI Implementors' Workshop Special Interest Group in Security is reviewing
-
- 55
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-
-
-
-
-
-
- the specifications of SDNS (See NISTIRs 90-4259 and 90-4262) as they become
- public. It is also reviewing proposals on security management. It has
- reviewed several security frameworks and architectures that may be used for
- future security standards development.
-
- 1.4 PLANS FOR ACHIEVEMENT
-
- The specifications and standards referenced above will be reviewed by the
- security staff of NIST, by the members of the OSI Implementors Workshop
- Security SIG and by members of the GOSIP committee for inclusion in one or
- more of the following: Federal Information Processing Standards; ANSI
- Standards; and ISO Standards. The following outlines the plans for satisfying
- the requirements for security in OSI, the development of public specifications
- and the development of standards incorporating the specifications.
-
- 1.4.1 OSI Security Architecture
-
- The OSI Security Architecture (IS 7498/2) was adopted as an International
- Standard in 1988. This document is included in the Implementors Agreements as
- being the basis for all OSI security development. No further work is needed on
- this document at this time.
-
- 1.4.2 OSI Security Frameworks
-
- A set of security frameworks of specific information processing applications
- are planned by the ISO/IEC/JTC 1/SC21/WG1 Security Group. An authentication
- framework is an example of such a framework. The Security SIG will continue
- to review these frameworks for adoption in the Implementors Agreements or to
- develop frameworks that are needed but are not in development in ISO.
-
-
-
-
-
- 1.4.3 Data Link Layer Security
-
- An IEEE Standard for Interoperable LAN Security is being developed over the
- next 1-2 years by the IEEE 802.10 LAN Security Working Group. A Standard for
- Interoperable LAN Security could be ready in 1990 for consideration by the OSI
- Implementors Workshop Security SIG.
-
- 1.4.4 Network Layer Security
-
- The SDNS Network Layer Security protocol document (SP3) is available for
- public use. This protocol was presented to ANSI in 1989. The protocol
- encapsulates the T-PDUs just like the Transport Layer security protocol except
- that it can also add network addresses to the protocol header for network
- routing. The protocol may be implemented in intermediate gateway systems as
- well as end systems. A Network Layer Security protocol standard could be
- ready in 1991.
-
- 1.4.5 Transport Layer Security
-
- 56
-
-
-
-
-
-
-
-
- The SDNS Transport Layer Security protocol document (SP4) is available for
- public use and a FIPS is being proposed based on this work. This protocol was
- presented to ANSI and ISO in 1989. The protocol encapsulates the Transport
- Protocol Data Units, adds an integrity code if integrity is desired, encrypts
- the entire T-PDU if confidentiality is desired, and then puts the result in a
- SE T-PDU (SE stands for security envelope or secure encapsulation). A
- receiver that has the correct cryptographic key can decrypt the SE T-PDU,
- verify its integrity and then process the resulting T-PDU. A Transport Layer
- Security protocol standard could be ready in 1991.
-
- 1.4.6 Electronic Message Handling System Security
-
- The X.400 Electronic Message Handling System security recommendations and the
- DARPA Mail Security RFC 1040 are available for public use. The SDNS Message
- Handling Security protocol specifications are also available for public use.
- A standard format for secure electronic messages could be ready in 1992.
-
- 1.4.7 Cryptographic Key Management Protocols
-
- The ANSI X9.17 Key Management Protocol, which is based on private key
- cryptographic algorithms, and several public key management protocols are
- being reviewed by the NIST security staff. A key management protocol based on
- public key cryptographic algorithms could be ready in 1993 for implementation.
-
-
-
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- 57
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-
-
-
- Figure A.1 Framework for OSI Security
-
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- 58
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-
-
- APPENDIX 2. SYSTEM AND ARCHITECTURE
-
-
- 2.1 Network Management
-
- OSI management functionality supports the location and correction of faults,
- the establishment and adjustment of configurations, the measurement and tuning
- of performance, the management of security, and collection and reporting of
- billing and accounting information. Such functionality is in end systems
- (hosts), intermediate systems (routers), and other network elements (e.g.,
- network services, bridges, switches, modems, and multiplexors). The primary
- goal for a Federal Government network management specification is to create
- the ability for managing multi-vendor computer and telecommunications networks
- remotely without undue use of proprietary management protocols. The scope of
- a network management specification for use by the U.S. Government will include
- protocols for exchanging management information and the definition and format
- of information to be exchanged.
-
- Note: The primary vehicle for this specification will be a Federal
- Information Processing Standard (FIPS). This FIPS will reference GOSIP and
- will be referenced by GOSIP. (The FIPS is discussed further below under
- "Plan".)
-
- Requirements
-
- Requirements for OSI network management are described in detail within a NIST
- report, Management of Networks Based on Open Systems Interconnection (OSI)
- Standards: Functional Requirements and Analysis (NIST Special Publication 500-
- 175, November 1989). Requirements exist for an overall management
- architectural framework model including fault, accounting, configuration,
- security, and performance management services.
-
- Status
-
- The OSI management standards are in an intermediate stage of their development
- and are progressing rapidly. Key areas for management standards are
- architecture, protocols, system management functions, and the structure of
- management information. The following table lists the latest available ISO
- schedule for management standards approved at the Sixth SC 21/WG 4 Meeting in
- Florence, October 31 - November 9, 1989.
-
- TARGET
- DATES
-
- DP DIS IS
- Management Architecture
- Management Framework 9/86 6/87 10/88
- Systems Management Overview 7/90
- 4/91
-
- Management Protocol
- Common Management Information Service
-
- 59
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-
-
-
-
-
-
- 1/90
- Addendum 1: CancelGet 9/89
- 7/90
- Addendum 2: Add/Remove 9/89
- 7/90
- Common Management Information Protocol
- 1/90
- Addendum 1: CancelGet 9/89
- 7/90
- Addendum 2: Add/Remove 9/89
- 7/90
-
- Structure of Management Information
- Part 1: Management Information Model 5/89
- 1/90 1/91
- Part 2: Definition of Management 7/90
- 4/91
- Information
- Part 4: Guidelines for the Definition 11/89
- 1/91 1/92
- of Managed Objects
- TARGET DATES
-
- DP DIS IS
- Management Functions
- Configuration Management
- Systems Management - Part 1:
- 7/90 7/91
- Object Management Function
- Systems Management - Part 2: 7/90
- 7/91
- State Management Function
- Systems Management - Part 3:
- 7/90 7/91
- Relationship Management Function
- Fault Management
- Systems Management - Part 4:
- 7/90 7/91
- Alarm Reporting Function
- Systems Management - Part 5:
- 7/90 7/91
- Event Report Management Function
- Systems Management - Part *: 7/90
- 4/91 4/92
- Confidence and Diagnostic Testing Function
- Systems Management - Part 6: 11/89
- 7/90 7/91
- Log Control Function
- Security Management
- Systems Management - Part 7: 11/89 7/90
- 7/91
- Security Alarm Reporting Function
-
- 60
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-
-
-
-
-
-
- Systems Management - Part *: 7/90 4/91
- 4/92
- Security Audit Trail Function
- Accounting Management
- Systems Management - Part *: 7/90 4/91
- 4/92
- Accounting Metering Function
- Performance Management
- Systems Management - Part *: 7/90 4/91
- 4/92
- Workload Monitoring Function
- Systems Management - Part *: 7/90
- 4/91 4/92
- Measurement Summarization Function
-
- As can be seen from the above schedule, there are several important standards
- that have now reached, or soon will reach, International Standard (IS) status.
- However, many others are still two years away from IS. Still others that are
- planned, e.g., Software Management (including "down-line load"), have not yet
- been added to the schedule. It is important to note that the Draft
- International Standards (DISs) scheduled to be available by the end of 1990
- comprise a subset that will make it possible for vendors to build useful
- systems to solve many immediate network management problems.
-
- Standards for the specification of managed objects are now being developed by
- ISO, ANSI, CCITT, and the IEEE, as well as by the Internet Engineering Task
- Force of the Internet Activities Board (for management of TCP/IP oriented
- networks). In general, full specifications and standards from these
- organizations are expected to lag the above SC21/WG4 management schedule by
- more than a year.
-
- Another important aspect of network management standards activity is the
- development of implementation agreements (IAs). The network management SIG of
- the NIST OIW is developing IAs based upon the emerging network management
- standards. These agreements are being developed according to a phased
- approach that aligns with the ISO standards as they progress from DP to IS.
- The OSI/NM Forum is also developing a set of agreements (termed
- specifications) for network management. These agreements, based on earlier
- ISO documents and original Forum work, are to be used as a basis for Forum-
- sponsored interoperable management demonstrations planned for 1990 and beyond.
- Both formal and informal liaison between the NMSIG of the OIW and the NM Forum
- has proved mutually beneficial in advancing each set of agreements, including
- identifying and correcting errors and omissions.
-
- Plan
-
- There is an urgent need today for products to manage multi-vendor computer and
- telecommunications networks. The U.S. Government requires initial network
- management specifications that provide a useful subset of the full OSI
- management functionality. It is desirable to specify the initial subset in
- such a way that it is easy to add other capabilities to reach the full set of
- management functionality. Such additional functionality may include the
-
- 61
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-
-
-
-
- management of future technologies such as ISDN and FDDI, and may include new
- management services such as software management and time management.
-
- The U.S. Government intends to propose an initial FIPS based on the OIW stable
- network management IAs. The OIW will include at most the following in its
- agreements to be completed in 1990 (from phase one of the OIW IAs):
-
- Management Functions:
- Object Management, State Management, Relationship Management, Error
- Reporting and Event Control
-
- Management Information:
- Information Model, Naming, Guidelines and Template for Defining Managed
- Objects
-
- Management Communication:
- CMIS/P, Association Policies, and Services Required
-
- Management Objects:
- Support Objects required for above and selected Managed Object
- Definitions under development by the OSI MIB WG
-
- Conformance Criteria:
- TBD depending on the progress of relevant ISO documents.
-
- It is planned that the initial network management FIPS will be based on
- portions of the above phase one stable agreements. The FIPS will include
- specifications for a management protocol based on OIW IAs for CMIS/CMIP, and
- it will include management function specifications based on the OIW IAs.
- Also, the FIPS will include a library of management objects (MIL). In
- addition, other portions of the agreements may be cited in the FIPS.
-
- GOSIP profiles will be cited in the FIPS to specify the protocol stack upon
- which management information will be conveyed and to include OSI applications
- suitable to support management of networks.
-
- Once an initial management FIPS has been established, portions of future GOSIP
- versions may reference management FIPS as appropriate. For example, to
- specify management of network end system (host) computers, GOSIP might
- reference the Network Management FIPS sections on the use of CMIS/CMIP as a
- method for conveying information and sections on system management functions
- for specific management services. GOSIP might also reference the management
- FIPS for appropriate managed object definitions. Likewise for the management
- of network routers, GOSIP might reference the FIPS for use of CMIS/CMIP,
- management functions and managed object definitions.
-
- These are possible initial examples. As both the FIPS and GOSIP mature, GOSIP
- will likely make many additional references to newer versions of the
- management FIPS. (And the FIPS can be expected to additionally reference
- newer versions of GOSIP as well.)
-
- 2.2 REGISTRATION
-
- 62
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-
-
-
-
-
-
-
- OSI Registration procedures are the key to creating globally unique
- identifiers for OSI objects. Most OSI objects are identified via a
- hierarchically structured label. Specific procedures must be established to
- ensure that GOSIP identifiers fit within an internationally recognized plan
- and uniquely identify GOSIP objects.
- Requirement
-
- Procedures are required for the registration of OSI objects, such as
- organization numbers and names. The specific complete list of objects is
- subject to further study and is likely to evolve over time, as directory
- services are adopted. For the first version of GOSIP, procedures were
- required for registration of organization identifiers for use in NSAPs, labels
- for electronic mail private body parts, and organization names for electronic
- mail addresses. The third version of GOSIP will require extending the
- procedures to include directory distinguished names. An immediate requirement
- not specific to GOSIP is registration procedures for objects defined in the
- OSI Implementor's Agreements.
-
- Status
-
- A standard for registration procedures is under development in ISO. The NIST
- is already maintaining a small registration service for OSINET members. The
- NIST has secured three international code designators (ICDs) as follows: 1)
- four (4) allocated to OSINET and the NIST/OSI Implementor's Workshop; 2) five
- (5) allocated to the U. S. Government, and 3) fourteen (14) allocated to the
- OSI Implementors' Workshop (OIW).
-
- Plan
-
- The NIST is updating the GOSIP User's Guide for publication with Version 2 of
- GOSIP. One section of the guide will detail GOSIP registration procedures. A
- registration SIG in the NIST OSI Implementors' Workshop has identified objects
- requiring registration and established detailed procedures for registering the
- objects.
-
- 2.3 ADDRESSING
-
- GOSIP network addressing is limited to defining NSAPs. The existing
- assumption is that NSAPs will be retrievable from a directory service and that
- each NSAP will address a single host. Nothing within GOSIP is designed to
- preclude multi-homed or mobile end systems. The problem is that no routing
- protocol exists to deal with mobile hosts at the speed required for some
- applications. At the present time, there is no definition for the semantics
- and syntax of multi-cast addressing within the network layer.
-
- Requirement
-
- Multi-cast addressing is required to support operation on broadcast networks
- with connectionless protocols.
-
- Status
-
- 63
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-
-
-
-
-
-
-
- No work is underway in this area.
-
- Plan
-
- Study inclusion of multi-cast NSAPs for operation over broadcast networks
- (e.g., local networks) in conjunction with connectionless transport, network,
- and data link protocols.
-
-
-
-
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-
-
-
- APPENDIX 3. UPPER LAYERS
-
-
- 3.1 X.400 EXTENSIONS
-
- Message Handling System specifications in Version 2 of GOSIP are based on the
- 1984 CCITT Recommendations. GOSIP MHS extensions will be based on the CCITT
- 1988 Recommendations. These recommendations provide new capabilities
- including security, delivery to a physical delivery service, use of a
- directory service, delivery to a message store, and an OSI architecture which
- includes ACSE and the Presentation layer.
-
- Requirements
-
- A requirement exists for MHS security features such as message originator
- authentication, checks against unauthorized disclosure and verification of
- content integrity. It is also highly desirable to have message store delivery
- which will allow personal computers without full User Agent functionality to
- have access to MHS services. The DOD requires that military precedence levels
- and preemption features be incorporated into the Message Handling Systems
- standard and that a method be developed of passing this information to the
- connectionless network layer protocol for processing.
-
- Status
-
- A. Standards - The 1988 CCITT MHS Recommendations were formally
- approved in late 1988.
-
- B. Implementors' Agreements - In 1989, the MHS SIG issued implementors'
- agreements which provided a minimally conformant 1988 Message Handling System.
- These implementors' agreements do not include significant additional user
- services, but allow interworking with implementations conforming to the NIST
- Stable Implementation Agreements for CCITT 1984 X.400-based Message Handling
- Systems and provide a firm basis for the introduction of further 1988 services
- and features. Further implementors' agreements based on CCITT 1988 X.400 are
- expected in 1990.
-
- Plan
-
- As an interim measure, NSA and NIST should determine whether the SDNS method
- of sending security information in a new special-purpose User Agent satisfies
- all GOSIP advanced security requirements for electronic mail. This approach
- would allow security information to be sent on Message Handling Systems
- implemented according to the CCITT 1984 Recommendations. However, the new
- User Agent would not be based on an international standard.
-
- There already exists the capability of sending and receiving X.400 mail from a
- personal computer attached to a host by using terminal emulation software.
- The User Agent is co-located with the MTA and the terminal interface is a
- local matter. The GOSIP Advanced Requirements Group plans to investigate to
- what extent this architecture satisfies current government requirements.
-
-
- 65
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-
-
-
-
-
-
- There is also a proposal to include a message store (i.e., standard remote
- User Agent) capability in a future MHS implementors' agreement. A message
- store would provide a standard software package with standard error recovery.
- When implementors' agreements for message store are adopted, the functionality
- in those agreements will be incorporated into GOSIP.
-
- The DoD requirement for expansion of precedence levels will be forwarded to
- the CCITT committee on Message Handling Systems. The GOSIP Advanced
- Requirements Group will request the NIST/OSI Implementors' Workshop to
- determine how Application-level precedents can be passed to the lower layers
- for processing.
-
-
-
- 3.2 FTAM (FILE TRANSFER, ACCESS AND MANAGEMENT)
-
- The File Transfer, Access and Management protocol and service allow users on
- different networks to communicate about files (and transfer files) without
- requiring that one user know the detailed file characteristics of the other
- user. A generic file organization is defined for communication; elements of
- this virtual file model are mapped to corresponding elements of the local file
- system. A comprehensive set of file attributes and file activity attributes
- are defined; in addition, a large number of actions is possible on a wide
- variety of file types.
-
- Requirement
-
- Implementation profiles are defined for user requirements as follows: simple
- file transfer, positional file transfer, full file transfer, simple file
- access, full file access, and management. Each implementation profile
- contains a different combination of document types, attributes and service
- classes. An FTAM implementation for the GOSIP should require support of the
- positional file transfer (which includes simple file transfer), simple file
- access and management implementation profiles. Future versions of GOSIP
- should include overlapped access, filestore management (including file
- directory query capability), error recovery capability, concurrency control
- capability, and File Access Data Unit (FADU) locking capability.
-
- Status
-
- A. Standards - FTAM has been released as an International Standard from
- ISO; currently FTAM comprises five parts: general introduction, virtual
- filestore definition, file service definition, file protocol specification,
- and protocol information conformance statement proforma. There are two
- prospective addenda which are overlapped access and filestore management.
- Filestore management should reach IS status in late 1991, and overlapped
- access should reach IS status in early 1992.
-
- B. Implementors' Agreements - FTAM Phase 2 (based on IS text) was
- completed as of December 1988, and maintained since then with the inclusion of
- several errata. This agreement provides for all core services defined in the
- FTAM standard except for restart, recovery and concurrency. Facilities for
-
- 66
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-
-
-
-
-
- full file transfer and record-level access are provided; three different FTAM,
- and four different NIST document types are defined. FTAM Phase 2 is included
- in Version 3 of the workshop agreements, available after December 1989. FTAM
- Phase 3 provides restart, recovery and concurrency capabilities, and enlarges
- on the set of document types currently defined. FTAM Phase 3 is complete as
- of March 1990. FTAM Phase 2 Agreements are upwardly compatible to FTAM Phase
- 3 Agreements at the intersection of their functional capabilities.
-
- Plan
-
- FTAM Phase 2 is currently included in versions 1 and 2 of GOSIP; reference is
- made to the Phase 2 FTAM (based on IS) as it appears in the workshop
- agreements. A file directory service capability is planned for in a future
- version of GOSIP; it is also anticipated that a number of new document types
- will be included in the future. Possibly, full file transfer and full file
- access implementation profiles will be mandated. Recovery, restart and
- concurrency control capabilities may also be required. It is anticipated that
- Version 3 of GOSIP will mandate the FTAM Phase 3 specification from the
- Workshop Agreements. NIST personnel will work with the FTAM Special Interest
- Group at the NIST/OSI Implementors' Workshop to expedite the development of
- implementation agreements and to insure that government requirements are
- included.
-
- 3.3 VIRTUAL TERMINAL
-
- The Basic Class Virtual Terminal Protocol allows terminals and hosts on
- different networks to communicate without requiring that one side know the
- terminal characteristics handled by the other side. A generic set of terminal
- characteristics is defined for communication which is mapped to local terminal
- characteristics for display. An addendum to Basic Class VT provides a forms
- mode capability.
-
-
-
- Requirement
-
- The service options to be selected include type of negotiation and the VT
- profiles to be specified. Additional implementation profiles for GOSIP will
- include profiles for page and scroll terminals in addition to the existing
- TELNET and forms profiles. No negotiation capability is required.
-
- Status
-
- A. Standards - All comments on Basic Class VT and on addendum 1 (forms)
- have been resolved and the service and protocol documents for Basic Class and
- the addendum have been merged.
-
- B. Implementors' Agreements - Stable agreements were completed for the
- TELNET, Transparent, and Forms profiles in December 1988. Stable Agreements
- for the X3 profile were completed in December 1989.
-
- Plan
-
- 67
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-
-
-
-
-
-
-
- Version 3 of GOSIP is expected to include the X3, scroll and page profiles.
- Additional options may be added to the TELNET profile. NIST personnel will
- work with the VT Special Interest Group in the NIST/OSI Implementors' Workshop
- to expedite the development of implementation agreements and to insure that
- government requirements are included.
-
- 3.4 THE DIRECTORY
-
- A directory is a collection of attributes (i.e., information) about, and
- relations between, a named set of addressable objects within a specific
- context. A directory can be viewed as a data base containing instances of
- record types. The most typical relationship between a directory user and the
- directory itself is that of an information user and an information provider.
- The user supplies an unambiguous or ambiguous key to the directory, and the
- directory returns the information labeled by the key. The directory user may
- filter the available information to access only the most essential fields.
-
- Requirement
-
- The requirements for a GOSIP directory service are much too complicated and
- voluminous to include here. The NIST has developed a separate report
- specifying the requirements. From the complete requirement set, the NIST has
- identified an initial subset for inclusion into GOSIP. In summary, for the
- initial directory, requirements include: 1) functions provided by the DoD
- "whois" service (a name to data record mapping), and the DoD domain name
- service (host name to network address mapping), 2) service name to T-selector,
- S-selector, and P-selector mapping, 3) inclusion of a host's capabilities
- within the host directory entry, and 4) the ability to resolve mailing list
- names into a set of electronic mail addresses. For the initial GOSIP
- directory, access control, simple authentication, and replication are also
- required.
-
- Status
-
- The Directory is an IS in ISO (ISO 9594) and has been issued by CCITT as the
- X.500 series of Recommendations. Workshop Agreements exist based on these
- documents. ISO and CCITT are jointly developing extensions to the current
- standard in areas where it is known to be deficient, such as access control,
- replication, and the information model. Additional implementation agreements
- are needed to cover the extensions.
-
- Plan
-
- The plan is to improve the directory implementor agreements as necessary and
- to get needed changes into the ISO and X.500 versions of the standard to
- support the initial GOSIP requirements. These goals should be accomplished in
- 1991 and 1992 so that an initial directory specification can be included in a
- subsequent version of GOSIP.
-
- 3.5 REMOTE DATABASE ACCESS
-
-
- 68
-
-
-
-
-
-
-
- Remote Database Access (RDA) allows the interconnection of database
- applications among heterogeneous environments by providing standard OSI
- Application layer protocols to establish a remote connection between a
- database client and a database server. The client is acting on behalf of an
- application program while the server is interfacing to a process that controls
- data transfers to and from a database.
-
- Requirement
-
- There is a strong requirement to share information among Database Management
- Systems from different vendors which are widespread in both government and
- industry. The Remote Database Access protocol allows that data sharing by
- providing a neutral "language" by which heterogeneous systems can communicate.
-
- An extension of the above requirement is the need for distributed database
- capability. This will be achieved in the long-term by extending the existing
- RDA model, and through RDA's harmonization with the Transaction Processing
- protocol.
-
- Status
-
- The RDA standard is specified in two documents, a generic RDA for arbitrary
- database connection and an SQL specialization for connecting databases
- conforming to the standard database language SQL. Both the generic RDA
- standard and the RDA specialization for SQL include functionality required by
- Federal agencies.
-
- The generic RDA standard reached DP status in 1987 and is expected to reach
- DIS status in 1990. The RDA specialization for SQL is also expected to reach
- DP status in 1990. Final adoption of ISO International Standards for both
- documents is expected in 1992.
-
- Plan
-
- Vendors, particularly SQL vendors, plan to have implementations conforming to
- the ISO International Standard available at the earliest possible time. An
- RDA SIG was formed within the NIST OSI Implementors' Workshop in 1989 to
- assist in this process.
-
- 3.6 TRANSACTION PROCESSING
-
- Requirement
-
- The specific requirements within the U. S. Government for transaction
- processing are still under investigation.
-
- Status
-
- Current plans are for Transaction Processing to move to IS status in 1990 or
- in 1991.
-
- Plan
-
- 69
-
-
-
-
-
-
-
-
- NIST is working with Federal agencies to determine transaction processing
- requirements and is representing the interests of Federal agencies in the
- national and international standards committees. The first step is for the
- federal agencies that have transaction processing requirements to become
- knowledgeable about the TP services specified in the evolving TP standards
- documents and to determine whether these services meet the needs of their
- organization. NIST is willing to assist other federal agencies in the
- process.
-
- A Transaction Processing SIG has been formed within the NIST/OSI Implementors'
- Workshop.
-
-
-
- 3.7 ELECTRONIC DATA INTERCHANGE
-
- Electronic Data Interchange (EDI) describes the rules and procedures that
- allow computers to send and receive business information in electronic form.
- Business information includes the full range of information associated with
- buyer/seller relationships (e.g., invoices, Customs declarations, shipping
- notices, purchase orders).
-
- Requirements
-
- The Office of Management and Budget is proposing to issue a guidance document
- that states that Federal agencies shall, to the maximum extent practicable,
- make use of Electronic Data Interchange with supporting GOSIP
- telecommunications networks for the processing of business-related
- transactions.
-
- Status
-
- A. Standards - 1) ANSI committee X12 has developed and is developing
- standard formats for business-related messages. There is also an ISO standard
- (IS 9735) for Electronic Data for Administration, Commerce and Transportation
- (EDIFACT). The JTC1 special working group on EDI is developing a conceptual
- model for Electronic Data Interchange. 2) CCITT Study Group VII established
- a Rapporteur Group to work on a solution on how to perform EDI using Message
- Handling Systems. The group completed work on a set of recommendations in
- June 1990. This group established a new content type for EDI and a
- corresponding content protocol (currently designated PEDI). PEDI will provide
- service elements and heading fields for EDI similar to those provided by P2
- for interpersonal messages.
-
- B. Implementors' Agreements - The NIST Workshop Agreements currently
- contains basic guidelines for adopting 1984 X.400 as the interim data
- transfer mechanism between EDI applications.
-
- Plan
-
- If products based on the CCITT Interim Recommendations are available in 1992,
-
- 70
-
-
-
-
-
-
-
- EDI will be included in Version 3 of GOSIP; Otherwise, EDI is scheduled for
- inclusion in Version 4 of GOSIP.
-
- 3.8 MMS SERVICES
-
- The Manufacturing Message Specification (MMS) application can be used to
- obtain and/or manipulate objects related to a manufacturing environment.
- These objects include, but are not limited to, variables semaphores, data
- types, and journals. Although MMS was designed for a manufacturing
- environment, these objects have applicability outside of manufacturing.
-
- Requirements
-
- Although the government is not a primary manufacturer, MMS has usefulness in
- the acquisition of point of measurement quality data, in military depots at
- the Department of Energy, and Department of Defense sites. Additionally, the
- Deep Space Network Data Systems group of the Jet Propulsion Laboratory is
- investigating the use of MMS for on-board control and telemetry.
-
- Status
-
- MMS is currently at the IS level in ISO and has implementors' agreements ready
- for inclusion in the NIST/OSI Stable Implementor Agreements in 1990.
-
- There are implementations available based upon DIS-9506(MMS) which are already
- installed. A mechanism for backwards compatibility has been agreed and is
- ready to progress into the Stable Agreements document. Work is ongoing to
- establish agreements on all 86 services that are contained within MMS.
-
-
- Plan
-
- The plan is to augment and improve the MMS implementors' agreements as
- required. Additionally, abstract test cases will be reviewed and generated as
- necessary to further refine the definition of MMS conformance. This work is
- ongoing with anticipated completion of a subset of services in 1990 so that
- MMS can be included in Version 3 of GOSIP.
-
- 3.9 INFORMATION RETRIEVAL
-
- Information retrieval supports the open interconnection of database users with
- database providers by specifying an OSI application layer protocol for
- intersystem search and retrieval of records from a remote bibliographic
- database.
-
- Requirement
-
- Information retrieval functionality is required by Federal agencies which need
- to retrieve information from remote bibliographic databases.
-
- Status
-
-
- 71
-
-
-
-
-
-
-
- The OSI Information Retrieval service and protocol is specified in the ANSI
- standard: Z39.50-1988 - Information Retrieval Service Definition and Protocols
- Specification for Library Applications. A corresponding ISO standard (ISO
- 10162 and 10163: Search and Retrieve Service Definition and Protocol
- Specification) has reached DIS status. Final adoption as international
- standards is expected by early 1991.
-
- Plan
-
- Vendors are now developing implementations conforming to Z39.50. A Z39.50
- implementor's group has been formed, represented by more than 20 companies.
- Options will be investigated to include bibliographic searching within GOSIP.
- Agencies are encouraged to bring forth other information retrieval
- requirements.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 72
-
-
-
-
-
-
-
- APPENDIX 4. EXCHANGE FORMATS
-
-
- The following standards are not OSI standards, but they provide services
- required by Federal agencies and the format information that they specify can
- be transferred by OSI Application layer protocols, such as FTAM and MHS.
-
- 4.1 ODA EXTENSIONS
-
- ODA allows for the interchange of compound documents (documents containing
- text, facsimile, and graphics) which have been generated by diverse types of
- office products, including word processors and desktop publishing systems.
- Interchange of ODA documents may be by means of data communications or the
- exchange of storage media. ODA documents may be in processable form (to allow
- further processing such as editing or reformatting) or in final form (to allow
- presentation as intended by the originator) or in both forms. The key concept
- in the document architecture is that of structure -- the division and repeated
- subdivision of the content of a document into increasingly smaller parts
- called objects. Two structures are defined by ODA: these are logical
- structure (contents are divided based on meaning, e.g., chapters, sections,
- paragraphs) and layout structure (contents are divided based on form, e.g.,
- pages, blocks).
-
- Requirement
-
- A Document Application Profile (DAP) specifies the constraints on document
- structure and content according to the rules of the ODA standard. Different
- DAPs can be created that apply to different classes of document. As
- extensions to ODA are made, they will be incorporated into the DAPs specified
- in the Workshop Agreements.
-
- Status
-
- A. Standards - ODA is an international standard; however, several areas
- within ODA are currently being studied, enhanced and/or extended. The primary
- emphasis on extensions includes new content architectures (such as
- spreadsheets and audio) and new features such as variant of styles, complex
- tables, alternative representation, computed data in documents, and an
- interface to EDI. Several addenda are planned to cover these extensions.
-
- B. Implementors' Agreements - The ODA SIG will examine extensions as they
- are developed to determine whether or not to incorporate such extensions in
- DAPs.
-
- Plan
-
- The plan is to contribute to the work on extensions to ODA through the
- Workshop by informing standards groups of deficiencies and inadequacies of the
- standard and to incorporate developed extensions into applicable DAPs when
- these extensions are mature. GOSIP will reference applicable DAPs which the
- National Computer Systems Laboratory (NCSL) plans to issue for Federal agency
- use.
-
- 73
-
-
-
-
-
-
-
-
- 4.2 GRAPHICS
-
- The graphics requirements for GOSIP include the Computer Graphics Metafile
- (CGM). The purpose of CGM is to facilitate the transfer of picture
- description information between different graphical software systems,
- different graphical devices and different computer graphics installations.
- CGM specifies a file format suitable for the description, storage and
- communication of picture description information in a device-independent
- manner.
-
- Requirement
-
- FIPS PUB 128 announces the adoption of the American National Standard for
- Computer Graphics Metafile, ANSI X3.122-1986, as a Federal Information
- Processing Standard (FIPS). This standard is intended for use in computer
- graphics applications that are either developed or acquired for government
- use. When computer graphics metafile systems for GOSIP are developed
- internally, acquired as part of an ADP system procurement, acquired by
- separate procurement, used under an ADP leasing arrangement, or specified for
- use in contracts for programming services, they shall conform to FIPS PUB 128.
-
- Status
-
- A. Standards - Computer Graphics Metafile (CGM) ANSI X3.122-1985, ISO
- 8632/1-4-1987, FIPS
- 128-1987.
-
- B. Application Profiles - MIL-D-28003 "Digital Representation of
- Communication of Illustration Data: CGM Application Profile" 30 December 1988.
-
- Plan
-
- An Application Profile (AP) defines additional requirements beyond ANSI CGM to
- ensure interoperability of implementations for specific applications.
- Currently, two major application profiles exist for CGM; the TOP AP, and the
- CALS AP (MIL-D-28003). As these APs and other APs which are applicable for
- Federal agency use are promulgated, they will be incorporated into FIPS 128.
- GOSIP will reference applicable APs for CGM which NCSL plans to issue for
- Federal agency use.
-
- 4.3 STANDARD GENERALIZED MARKUP LANGUAGE (SGML) APPLICATION PROFILE
-
- Description
-
- The Standard Generalized Markup Language (SGML) standardizes the application
- of the generic coding and generalized markup concepts. It provides a coherent
- and unambiguous syntax for describing whatever a user chooses to identify
- within a document. It is a metalanguage for describing the logical and
- content structure of a document in a machine processable syntax. The Standard
- Generalized Markup Language can be used for documents that are processed by
- any text processing or word processing system. It will be particularly
-
- 74
-
-
-
-
-
-
-
- applicable to:
-
- o documents that are interchanged among systems with differing text
- processing languages
-
- o documents that are processed in more than one way, even when the
- procedures use the same text processing language.
-
- Requirement
-
- FIPS PUB 152 announces the adoption of the International Standards
- Organization Standard Generalized Markup Language (SGML), ISO 8879-1986, as a
- Federal Information Processing Standard (FIPS). This standard is intended for
- use in documents that are processed by any text processing systems that are
- either developed or acquired for government use. When SGML text processing
- systems for GOSIP are developed internally, acquired as part of an ADP system
- procurement, acquired by separate procurement, used under an ADP leasing
- arrangement, or specified for use in contracts for programming services, they
- shall conform to FIPS PUB 152.
-
-
- Status
-
- A. Standards - Information Processing - Text and office systems -
- Standard Generalized Markup Language (SGML), ISO 8879-1986 (E),FIPS 152-1988.
-
- B. Application Profiles - MIL-M-28001A, "Markup Requirements and
- Generic Style Specification for Electronic Printed Output and Exchange of
- Text," December 1989.
-
- MIL-M-28001A, "Markup Requirements and Generic Style Specifications for
- Electronic Printed Output and Exchange of Text," established the requirements
- for the digital data form of page oriented technical military publications.
- Data prepared in conformance to these requirements will facilitate the
- automated storage, retrieval, interchange, and processing of technical
- documents from heterogeneous data sources. MIL-M-28001A requirements include:
-
- o procedures and symbology for markup of unformatted text in accordance
- with this specific application of the Standard Generalized Markup
- Language;
-
- o SGML compatible codes that will support encoding of a technical
- publication to specific format requirements applicable to technical
- manuals;
-
- o output processing requirements that will format a conforming SGML source
- file to the style and format requirements of the appropriate Formatting
- Output Specification Instance (FOSI).
-
- Plan
-
- An Application Profile (AP) defines additional requirements beyond FIPS SGML
-
- 75
-
-
-
-
-
-
-
- to ensure interoperability of implementation. MIL-M-28001 is an Application
- Profile for technical military publications. The plan is to develop an SGML
- Document Application Profile (SDAP) by extending MIL-M-28001 to be more useful
- for generic documents and to incorporate the SDAP into FIPS 152. GOSIP will
- reference applicable SDAPs which NCSL plans to issue for Federal agency use.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 76
-
-
-
-
-
-
-
- APPENDIX 5. LOWER LAYER PROTOCOLS
-
-
- 5.1 IS-IS DYNAMIC ROUTING PROTOCOLS
-
- Within OSI networks, systems of routers (intermediate systems) enable the
- effective and efficient interconnection of a diverse set of subnetwork types
- (e.g., CSMA/CD, token ring, token bus, and X.25) into internetworks. Within
- such an internetwork, messages are sent like postal letters from router to
- router. At each router a message is examined and the next router is selected.
- The effect of such a scheme is that each message may follow an independent
- route. As conditions within the internetwork change (e.g., link, host, and
- router failures and activations), the possibility exists for messages to reach
- their destination despite failure of network elements. Such potential can
- only be achieved if the system of routers exchanges information concerning the
- state of routes. Protocols for exchanging information concerning varying
- route conditions are known as dynamic routing protocols. Within OSI
- standards, dynamic routing protocols are named intermediate system to
- intermediate system (IS-IS) protocols.
-
- Requirement
-
- Dynamic routing is required within GOSIP to support the needs of several large
- government internetworks. Two kinds of routing support are required: 1)
- dynamic routing within an administrative domain, and 2) dynamic routing
- between administrative domains. Routing requirements within an administrative
- domain are well understood, and two generally acceptable schemes exist.
- Routing requirements between administrative domains are not widely agreed
- upon, although ECMA has produced a technical report.
-
- Status
-
- An intra-domain dynamic routing protocol was submitted to ISO from ASC X3S53.3
- in January 1988. The submission is based on DEC's Phase V link state routing.
- It was discussed at the November ISO SC6/WG2 meeting and was registered as a
- DP in January 1990.
-
- ECMA developed an inter-domain technical report (TR50), based on an NIST-
- developed model. It was submitted by ECMA as a liaison to ISO WG2 in May 1989
- as the proposed basis for an ISO inter-domain standard.
-
- Plan
-
- The NIST will support the progression of the DEC submission toward an ISO IS
- through work in standards committees and laboratories. The NIST will also
- prepare for establishing implementor agreements as the document reaches DIS.
- The NIST will continue to support development of the inter-domain routing
- protocol within ECMA, ANSI, and ISO.
-
- The GOSIP will adopt intra-domain dynamic routing protocols as soon as
- implementor agreements are in place. The projected date is 1991. The
- adoption of an inter-domain routing protocol for GOSIP should occur one to two
-
- 77
-
-
-
-
-
-
-
- years following adoption of an intra-domain protocol.
-
- 5.2 FIBER DISTRIBUTED DATA INTERFACE (FDDI)
-
- FDDI is a 100 Mbit/s token ring network utilizing multimode fiber optic media.
- Three standards, Physical Medium Dependent (PMD), Physical Layer Protocol
- (PHY), and Medium Access Control (MAC) specify the Physical and Data Link
- layers of the Open Systems Interconnection Reference Model. A fourth
- standard, Station Management (SMT) interfaces to the first three layers to
- control initialization and configuration of the ring, as well as
- reconfiguration around faults, and will provide management services to higher
- layer management protocols.
-
-
-
- Requirement
-
- MAC, PHY and PMD have a few options which require selection (e.g., 48 bit vs.
- 16 bit addressing) and a few timers and parameters which require further
- definition (particularly of their default values) to ensure interoperability
- in an OSI environment. One class of service (Restricted Token Mode) is
- inappropriate in an OSI environment.
-
- SMT is more complex, and will probably offer many options, particularly
- regarding network policies, which will require some selection. In many cases,
- this will simply mean selecting the default option or policy.
-
- Status
-
- A. Standards - The MAC (X3.139-1987) PHY (X3.148-1988) and PMD (X3.166-
- 1989) standards are approved. SMT is still under development and probably
- will be forwarded in June 1990 and approved in 1991. Products implementing
- FDDI are now widely available.
-
- B. Implementors' Agreements - NIST has drafted an implementors'
- agreement covering MAC, PHY and PMD. This was accepted into the ongoing
- agreements by the Lower Level SIG and should be incorporated in Version 3.0 of
- GOSIP. Although products are now starting to appear, SMT is not approved, but
- is "stable", so work could begin on an implementors' agreement by mid-1990.
-
- Plan
-
- NIST will draft a proposed implementors' agreement covering SMT after SMT is
- forwarded to approval, which will probably occur in June. The ANSI standard,
- moreover, will not be completely stable until some time in 1990 or 199l, since
- the public review usually results in changes. That means that closure on
- implementors' agreements cannot be reached before some time in 1991 at the
- earliest. This is not ideal, because there will be significant product
- shipments in 1990.
-
- Since SMT is largely software, vendors expect to update equipment already
- shipped before SMT is finalized, by distributing new software (often on ROM
-
- 78
-
-
-
-
-
-
-
- chips).
-
- 5.3 TRANSPORT PROTOCOL CLASS 2
-
- The transport protocol, class 2, for use over the connection-oriented network
- service (CONS) is accepted by several OSI profiles (e.g., UK GOSIP). The
- transport protocol, class 2, is also used with CONS in several U.S. Government
- applications, where communication is confined to a single logical subnetwork.
-
- Requirement
-
- The transport protocol, class 2, is desired in GOSIP as an optional transport
- protocol for use with CONS, where communication is confined to a single
- logical subnetwork. The transport protocol, class 4, operating over the
- connectionless network service (CLNS), will remain the sole mandatory data
- transport service for purposes of interoperability among U. S. GOSIP-compliant
- computer systems. The specification of the transport protocol, class 2, as an
- option in GOSIP, is intended to enable interoperability among U.S. Government
- computer systems, when using class 2 transport over CONS. Such specifications
- would be intended to prevent the spread of non-interoperable class 2 transport
- implementations within the U. S. Government. The ability to choose the
- correct transport protocol class for a given instance of communication will
- require a prior knowledge on the part of the transport connection initiator,
- until directory services are included in GOSIP.
-
- Status
-
- Although a few U.S. vendors provide implementations of the class 2 transport
- protocol, the overwhelming majority offer class 4 transport only. The
- Workshop Agreements endorse class 4 transport for use over
-
- CLNS and CONS, and class 0 transport for use over CONS when direct access to
- public messaging systems is required.
-
- Plan
-
- Interested government agencies brought the requirement for class 2 transport
- implementation agreements to the attention of the Lower Layer SIG of the
- NIST/OSI Implementors' Workshop. Workshop Agreements are now in place, so
- consideration canbe given to inclusion of an optional class 2 transport
- capability into GOSIP, Version 3.0.
-
- 5.4 INTEGRATED SERVICES DIGITAL NETWORK
-
- Integrated Services Digital Networks (ISDN), supporting integrated voice,
- data, image, and video are expected to be deployed on a wide scale in
- ubiquitous public offerings and in private network offerings, as services and
- as components from which private ISDN networks can be constructed. Initial
- offerings will be a switched 64 kbps service delivered to a customer's
- terminal at a basic rate (16 Kbps signaling channel and two 64 KBPS data
- channels) or a primary rate (24 64 Kbps channels, one used for signalling).
- Later offerings, now in the development phases, will offer higher capacities,
-
- 79
-
-
-
-
-
-
-
- estimated at 150 Mbps to 622 Mbps.
-
- Requirement
-
- One use for ISDN is to provide a bearer service for OSI data protocols; thus,
- ISDN is included in GOSIP as a lower layer service. Other ISDN applications
- include integrated voice, image, data, and video, and, therefore, non-GOSIP
- ISDN applications can be expected. NIST plans to issue a variety of FIPS that
- enable the government to exploit the full technical capabilities of ISDN. The
- initial focus aims at switched 64 Kbps service for voice, voice/data, and, in
- GOSIP, OSI data. Both the basic and primary rates are needed. Later
- broadband ISDN (B-ISDN) is needed. The initial fundamental requirements are:
- 1) specifications enabling multi-vendor interconnection compatibility between
- terminal equipment and switching equipment and 2) specifications enabling
- multi-vendor interconnection compatibility between switching equipment.
-
- Status
-
- The North American ISDN Users Forum (NIU-FORUM), comprising a user's workshop
- (IUW) and an implementor's workshop (IIW), is addressing issues of multi-
- vendor terminal equipment-to-switch and switch-to-switch interoperation and
- ISDN application profiles. Some implementation agreements and application
- profiles are expected by the end of 1990.
-
- Plan
-
- The GOSIP FIPS will reference appropriate IIW agreements and ISDN FIPS as they
- become available. NIST plans to issue ISDN FIPS for integrated voice, image,
- data, and video and non-OSI data, as appropriate agreements are achieved in
- the IIW and IUW. The primary requirement for ISDN in GOSIP is as a network
- bearer service accessible via terminal equipment and switching equipment that
- can be connected readily, regardless of the specific vendor. The GOSIP FIPS
- will evolve to account for availability of B-ISDN and the Synchronized Optical
- Network (SONET).
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- 80
-
-
-
-
-
-
-
- APPENDIX 6. ACRONYMS
-
-
- ACSE Association Control Service Element
- AE Application Entity
- AFI Authority and Format Identifier
- ANSI American National Standards Institute
- AP Application Profile
- ASCII American Standard Code for Information Interchange
- ASN Abstract Syntax Notation
- BRI Basic Rate Interface
- CCITT Consultative Committee for International Telegraph & Telephone
- CGM Computer Graphics Metafile
- CLNP Connectionless Network Protocol
- CLNS Connectionless Network Service
- CLTP Connectionless Transport Protocol
- CLTS Connectionless Transport Service
- CMIP Common Management Information Protocol
- CMIS Common Management Information Services
- CONS Connection-Oriented Network Service
- COTS Connection-Oriented Transport Service
- CSMA/CD Carrier Sense, Multiple Access with Collision Detection
- DAP Document Application Profile
- DIS Draft International Standard
- DOD Department of Defense
- DOE Department of Energy
- DP Draft Proposal
- DSP Domain Specific Part
- DTR Draft Technical Report
- ECMA European Computer Manufacturers Association
- EIA Electronic Industries Association
- ES-IS End System-Intermediate System
- FADU File Access Data Unit
- FAR Federal Acquisition Regulation
- FDDI Fiber Distributed Data Interface
- FIB Forwarding Information Base
- FIPS Federal Information Processing Standard
- FIRMR Federal Information Resources Management Regulation
- FTAM File Transfer, Access, and Management
- GENSER General Service
- GOSIP Government Open Systems Interconnection Profile
- GSA General Services Administration
- HDLC High Level Data Link Control
- ICD International Code Designator
- IDI Initial Domain Identifier
- IDP Initial Domain Part
- IEC International Electrotechnical Commission
- IEEE Institute of Electrical and Electronic Engineers
- IRV International Reference Version
- IS International Standard
- IS Intermediate System
- IS-IS Intermediate System-Intermediate System
-
- 81
-
-
-
-
-
-
-
- ISDN Integrated Services Digital Network
- ISO International Organization for Standardization
- JTC Joint Technical Committee
- LAN Local Area Network
- LAPB Link Access Procedure B
- LAPD Link Access Procedure D
- MAC Medium Access Control
- MAP Manufacturing Automation Protocol
- MHS Message Handling Systems
- MMS Manufacturing Message Specification
- NCS National Communications System
- NIST National Institute of Standards and Technology
- NMSIG Network Management Special Interest Group
- NPDU Network Protocol Data Unit
- NPAI Network Protocol Access Information
- NSA National Security Agency
- NSAP Network Service Access Point
- ODA Office Document Architecture
- OSIO Open Systems Interconnection
- PCI Protocol Control Information
- PDN Public Data Network
- PDU Protocol Data Unit
- PHY Physical Layer Protocol
- PLP Packet Level Protocol
- PMD Physical Medium Dependent
- PRI Primary Rate Interface
- PSAP Presentation Service Access Point
- RDA Remote Database Access
- RFP Request For Proposal
- RIB Routing Information Base
- SAP Service Access Point
- SC Steering Committee
- SCI Special Compartmented Information
- SDNS Secure Data Network Service
- SGML Standard Generalized Markup Language
- SIG Special Interest Group
- SILS Standard for Interoperable LAN Security
- SIOP-ESI Single Integrated Operational Plan-Extremely Sensitive Info.
- SMT Station Management
- SNPA Subnetwork Point of Attachment
- SQL Structured Query Language
- SSAP Session Service Access Point
- SVC Switched Virtual Circuit
- TC Technical Committee
- TOP Technical and Office Protocols
- TP Transaction Processing
- TSAP Transport Service Access Point
- TTY Teletype
- VT Virtual Terminal
- WAN Wide Area Network
- WG Working Group
- WYSIWYG What You See Is What You Get
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- 82
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- 83
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