ISO 12174:2003

Space data and information transfer systems — Telecommand — Architectural specification for the data management service

ISO 12174:2003 specifies the requirements, which define the architecture of a spacecraft telecommand data management service. This architecture is intended to provide a common framework within which space agencies may implement compatible future spacecraft telecommanding systems. ISO 12174:2003 primarily addresses the data unit formats and functions, which are implemented within the application process layer, the system management layer and the packetization layer of the CCSDS telecommand data management service.

Systèmes de transfert des informations et données spatiales — Télécommande — Définition architecturale du service de gestion des données

General Information

• Status: Withdrawn
• Publication Date: 11-Feb-2003
• Withdrawal Date: 11-Feb-2003
• ICS: 49.140 - Space systems and operations
• Technical Committee: ISO/TC 20/SC 13 - Space data and information transfer systems
• Drafting Committee: ISO/TC 20/SC 13 - Space data and information transfer systems
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 05-Mar-2007

Relations

• Revises: ISO 12174:1998 - Space data and information transfer systems — Telecommand — Data management service — Architectural specification
• Effective Date: 15-Apr-2008

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 12174
Second edition
2003-02-15

Space data and information transfer
systems — Telecommand —
Architectural specification for the data
management service
Systèmes de transfert des informations et données spatiales —
Télécommande — Définition architecturale du service de gestion des
données




Reference number
ISO 12174:2003(E)
©
ISO 2003

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ISO 12174:2003(E)
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ISO 12174:2003(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 12174 was prepared by the Consultative Committee for Space Data Systems
(CCSDS) (as CCSDS 203.0-B-2, June 2001) and was adopted (without modifications except those stated in
Clause 2 of this International Standard) by Technical Committee ISO/TC 20, Aircraft and space vehicles,
Subcommittee SC 13, Space data and information transfer systems.
This second edition cancels and replaces the first edition (ISO 12174:1998), which has been technically
revised.




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INTERNATIONAL STANDARD ISO 12174:2003(E)

Space data and information transfer systems —
Telecommand — Architectural specification for the data
management service
1 Scope
This International Standard specifies the requirements which define the architecture of a spacecraft
telecommand data management service. This architecture is intended to provide a common framework within
which space agencies may implement compatible future spacecraft telecommanding systems.
The scope and field of application are furthermore detailed in subclauses 1.1 and 1.2 of the enclosed CCSDS
publication.
2 Requirements
Requirements are the technical recommendations made in the following publication (reproduced on the
following pages), which is adopted as an International Standard:
CCSDS 203.0-B-2, June 2001, Recommendation for space data system standards — Telecommand —
Part 3: Data management service — Architectural specification.
For the purposes of international standardization, the modifications outlined below shall apply to the specific
clauses and paragraphs of publication CCSDS 203.0-B-2.
Pages i to v
This part is information which is relevant to the CCSDS publication only.
Page 1-3
Add the following information to the references indicated:
[1] Document CCSDS 202.0-B-3, June 2001, is equivalent to ISO 12172:2003.
[2] Document CCSDS 201.0-B-3, June 2000, is equivalent to ISO 12171:2003.
[3] Document CCSDS 102.0-B-5, November 2000, is equivalent to ISO 13419:2003.
[4] Document CCSDS 101.0-B-5, June 2001, is equivalent to ISO 11754:2003.
[5] Document CCSDS 713.0-B-1, May 1999, is equivalent to ISO 15891:2000.
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ISO 12174:2003(E)
3 Revision of publication CCSDS 203.0-B-2
It has been agreed with the Consultative Committee for Space Data Systems that Subcommittee
ISO/TC 20/SC 13 will be consulted in the event of any revision or amendment of publication
CCSDS 203.0-B-2. To this end, NASA will act as a liaison body between CCSDS and ISO.


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ISO 12174:2003(E)

Consultative
Committeefor
SpaceDataSystems




RECOMMENDATION FOR SPACE
DATA SYSTEM STANDARDS


TELECOMMAND
PART 3
DATA MANAGEMENT SERVICE
ARCHITECTURAL SPECIFICATION



CCSDS 203.0-B-2

BLUE BOOK


June 2001


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ISO 12174:2003(E)
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
AUTHORITY


Issue: Blue Book, Issue 2
Date: June 2001
Location: Oxfordshire, UK



This document has been approved for publication by the Management Council of the
Consultative Committee for Space Data Systems (CCSDS) and represents the consensus
technical agreement of the participating CCSDS Member Agencies. The procedure for
review and authorization of CCSDS Recommendations is detailed in the Reference [C1], and
the record of Agency participation in the authorization of this document can be obtained from
the CCSDS Secretariat at the address below.


This Recommendation is published and maintained by:

CCSDS Secretariat
Program Integration Division (Code MT)
National Aeronautics and Space Administration
Washington, DC 20546, USA
CCSDS 203.0-B-2 Page i June 2001
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
STATEMENT OF INTENT


The Consultative Committee for Space Data Systems (CCSDS) is an organization officially
established by the management of member space Agencies. The Committee meets
periodically to address data systems problems that are common to all participants, and to
formulate sound technical solutions to these problems. Inasmuch as participation in the
CCSDS is completely voluntary, the results of Committee actions are termed
RECOMMENDATIONS and are not considered binding on any Agency.

This RECOMMENDATION is issued by, and represents the consensus of, the CCSDS
Plenary body. Agency endorsement of this RECOMMENDATION is entirely voluntary.
Endorsement, however, indicates the following understandings:

o Whenever an Agency establishes a CCSDS-related STANDARD, this STANDARD
will be in accord with the relevant RECOMMENDATION. Establishing such a
STANDARD does not preclude other provisions which an Agency may develop.

o Whenever an Agency establishes a CCSDS-related STANDARD, the Agency will
provide other CCSDS member Agencies with the following information:

-- The STANDARD itself.

-- The anticipated date of initial operational capability.

-- The anticipated duration of operational service.

o Specific service arrangements shall be made via memoranda of agreement. Neither this
RECOMMENDATION nor any ensuing STANDARD is a substitute for a
memorandum of agreement.

No later than five years from its date of issuance, this Recommendation will be reviewed by
the CCSDS to determine whether it should: (1) remain in effect without change; (2) be
changed to reflect the impact of new technologies, new requirements, or new directions; or
(3) be retired or cancelled.
CCSDS 203.0-B-2 Page ii June 2001
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
FOREWORD


This document, which is a technical Recommendation prepared by the Consultative
Committee for Space Data Systems (CCSDS), is intended for use by participating space
Agencies in their development of space telecommand systems.
This Recommendation allows the implementing organizations within each Agency to
proceed coherently with the development of compatible Standards for the flight and ground
systems that are within their cognizance. Agency Standards derived from this
Recommendation may implement only a subset of the optional features allowed herein, or
may incorporate features not addressed by the Recommendation.
In order to establish a common framework within which the Agencies may develop
standardized telecommand services, the CCSDS advocates adoption of a layered systems
architecture. Within this approach, specific layers of service (including their operational
protocol and data structuring techniques) may be selected for implementation according to
mission requirements.
The current layered set of CCSDS telecommand Recommendations was developed to match
the conventional free-flying mission environment, as characterized by the transmission of
command data at relatively low uplink data rates to spacecraft of moderate complexity. The
CCSDS is currently examining the extension of these Recommendations (perhaps by
defining expanded protocols and data structures within some of the layers) to a more
complex mission environment, including the transmission of multiple data types at very high
data rates to space vehicles which include extensive onboard data networking capability.
This Recommendation for Telecommand Data Management Service was developed within
the layered architectural framework, and embraces the standard data structures and data
communication procedures which may be used by conventional missions within the highest
telecommand system layers.
Through the process of normal evolution, it is expected that expansion, deletion or
modification to this document may occur. This Recommendation is therefore subject to
CCSDS document management and change control procedures defined in Reference [C1].
Current versions of CCSDS documents are maintained at the CCSDS Web site:
http://www.ccsds.org/
Questions relating to the contents or status of this Report should be addressed to the CCSDS
Secretariat at the address on page i.
CCSDS 203.0-B-2 Page iii June 2001
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
At time of publication, the active Member and Observer Agencies of the CCSDS were:

Member Agencies

– Agenzia Spaziale Italiana (ASI)/Italy.
– British National Space Centre (BNSC)/United Kingdom.
– Canadian Space Agency (CSA)/Canada.
– Centre National d’Etudes Spatiales (CNES)/France.
– Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR)/Germany.
– European Space Agency (ESA)/Europe.
– Instituto Nacional de Pesquisas Espaciais (INPE)/Brazil.
– National Aeronautics and Space Administration (NASA)/USA.
– National Space Development Agency of Japan (NASDA)/Japan.
– Russian Space Agency (RSA)/Russian Federation.

Observer Agencies

– Austrian Space Agency (ASA)/Austria.
– Central Research Institute of Machine Building (TsNIIMash)/Russian Federation.
– Centro Tecnico Aeroespacial (CTA)/Brazil.
– Chinese Academy of Space Technology (CAST)/China.
– Commonwealth Scientific and Industrial Research Organization (CSIRO)/Australia.
– Communications Research Centre (CRC)/Canada.
– Communications Research Laboratory (CRL)/Japan.
– Danish Space Research Institute (DSRI)/Denmark.
– European Organization for the Exploitation of Meteorological Satellites
(EUMETSAT)/Europe.
– European Telecommunications Satellite Organization (EUTELSAT)/Europe.
– Federal Service of Scientific, Technical & Cultural Affairs (FSST&CA)/Belgium.
– Hellenic National Space Committee (HNSC)/Greece.
– Indian Space Research Organization (ISRO)/India.
– Institute of Space and Astronautical Science (ISAS)/Japan.
– Institute of Space Research (IKI)/Russian Federation.
– KFKI Research Institute for Particle & Nuclear Physics (KFKI)/Hungary.
– MIKOMTEK: CSIR (CSIR)/Republic of South Africa.
– Korea Aerospace Research Institute (KARI)/Korea.
– Ministry of Communications (MOC)/Israel.
– National Oceanic & Atmospheric Administration (NOAA)/USA.
– National Space Program Office (NSPO)/Taipei.
– Swedish Space Corporation (SSC)/Sweden.
– United States Geological Survey (USGS)/USA.

CCSDS 203.0-B-2 Page iv June 2001
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
DOCUMENT CONTROL
Document Title and Issue Date Status
CCSDS Telecommand Part 3— January 1987 Original Issue (superseded).
203.0-B-1 Data Management Service,
Issue 1
Current Issue:
CCSDS Telecommand Part 3— June 2001
adds specifications to
203.0-B-2 Data Management Service,
support use of TC
Issue 2
Transfer Frame to
transport various types of
packets, including TC
Packets, CCSDS Network
Protocol (NP) datagrams,
and Internet Protocol (IP)
datagrams.
NOTE:  Substantive changes from the previous issue are flagged with change bars in the
inside margin.

CCSDS 203.0-B-2 Page v June 2001
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
CONTENTS


Sections Page

1 INTRODUCTION. 1-1

1.1 PURPOSE AND SCOPE. 1-1
1.2 APPLICABILITY.1-1
1.3 BIT NUMBERING CONVENTION AND NOMENCLATURE. 1-2
1.4 REFERENCES.1-3

2 TELECOMMAND DATA MANAGEMENT SERVICE OVERVIEW. 2-1
3 APPLICATION PROCESS LAYER: STANDARD DATA STRUCTURES AND
PROCEDURES . 3-1

3.1 OVERVIEW OF THE LAYER . 3-1
3.2 STANDARD DATA STRUCTURES WITHIN THE LAYER. 3-3
3.3 STANDARD PROCEDURES WITHIN THE LAYER . 3-3

4 SYSTEM MANAGEMENT LAYER: STANDARD DATA STRUCTURES AND
PROCEDURES . 4-1

4.1 OVERVIEW OF THE LAYER . 4-1
4.2 STANDARD DATA STRUCTURES WITHIN THE LAYER. 4-2
4.3 STANDARD PROCEDURES WITHIN THE LAYER . 4-2

5 PACKETIZATION LAYER: STANDARD DATA STRUCTURES AND
PROCEDURES . 5-1

5.1 OVERVIEW OF THE LAYER . 5-1
5.2 CCSDS TELECOMMAND PACKET . 5-1
5.3 OTHER TYPES OF PACKETS . 5-6
5.4 STANDARD PROCEDURES WITHIN THE LAYER . 5-9

ANNEX A DATA MANAGEMENT SERVICE  ACRONYMS AND
TERMINOLOGY . A-1
ANNEX B DATA MANAGEMENT SERVICE SPECIFICATION. B-1
ANNEX C INFORMATIVE REFERENCES. C-1
CCSDS 203.0-B-2 Page vi June 2001
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
CONTENTS

Figure Page

2-1 Telecommand System .2-2
3-1 Application Process Layer Functional Overview.3-2
5-1 Telecommand Packet Format.5-2


CCSDS 203.0-B-2 Page vii June 2001
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ISO 12174:2003(E)
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
1 INTRODUCTION
1.1 PURPOSE AND SCOPE
The purpose of this document is to establish a common Recommendation which defines the
systems architecture of a spacecraft telecommand "Data Management Service". The intent of
this architecture is to provide a common framework within which the Agencies participating
in the Consultative Committee for Space Data Systems (CCSDS) may implement compatible
future spacecraft telecommanding systems. The operating principles and procedures for the
CCSDS are defined in Reference [C1]. The context of the Data Management Service within
the overall Telecommand System is described in Reference [C2].
This Recommendation primarily addresses the data unit formats and functions which are
implemented within the the Application Process layer, the System Management layer and the
Packetization layer of the CCSDS telecommand Data Management Service. Recognizing
that much future work remains to be done relative to these top layers, their specification has
been deliberately minimized by the CCSDS. IN PARTICULAR, THE DETAILED
OPERATIONAL PROTOCOLS WHICH OPERATE ACROSS THESE LAYERS,
AND THE FLOW OF CONTROL INFORMATION REQUIRED TO INITIALIZE
THE LAYERS AND DIRECT THE TRANSFER OF DATA BETWEEN THEM, ARE
NOT PRESENTLY ADDRESSED WITHIN THIS DOCUMENT: THESE REMAIN
ITEMS FOR POTENTIAL EXTENSION OF THIS RECOMMEN- DATION.
1.2 APPLICABILITY
This Recommendation serves as a guideline for the development of compatible internal
Agency standards in field of spacecraft commanding. This Recommendation is not
retroactive, nor does it commit any Agency to implement the recommended telecommand
concepts at any future time. Nevertheless, all CCSDS Agencies accept the principle that all
future implementations of telecommand which are used in cross-support situations will be
based on this Recommendation.
The CCSDS has developed a layered concept for future spacecraft telecommanding, which is
fully described in Reference [C2]. Standard services are defined within each layer, and
Agencies will be encouraged to develop corresponding facilities to provide these services in
support of Projects.  To be fully compatible with the CCSDS concept, a Project's
telecommanding architecture should follow this Recommendation for Data Management
Service, plus the Recommendations for telecommand "Data Routing Service" and
telecommand "Channel Service" which are described in References [1] and [2]. Projects
may also elect to be partially compatible with the concept by interfacing with the standard
systems at intermediate layers within any of the service specifications.
CCSDS 203.0-B-2 Page 1-1 June 2001
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
Where preferred options or mandatory capabilities are clearly indicated herein, the indicated
sections of the specification must be implemented when this Recommendation is used as a
basis for cross-support. Where optional subsets or capabilities are allowed or implied in this
specification, implementation of these options or subsets is subject to specific bilateral cross-
support agreements between the Agencies involved.
The recommendations in this document are to be invoked through the normal standards
programs of each member Agency, and are applicable to those missions for which cross-
support based on capabilities described in these recommendations is anticipated.
No later than five years from its date of issue, this Recommendation should be reviewed by
the CCSDS Agencies to determine whether it should: 1) remain in effect without change; 2)
be changed to reflect the impact of new technologies, new requirements, or new directions;
or 3) be retired or canceled.
1.3 BIT NUMBERING CONVENTION AND NOMENCLATURE
In this document, the following convention is used to identify each bit in an N-bit field. The
first bit in the field to be transmitted (i.e., the most left justified when drawing a figure) is
defined to be "Bit 0"; the following bit is defined to be "Bit 1" and so on up to "Bit N-1".
When the field is used to express a binary value (such as a counter), the Most Significant Bit
(MSB) shall be the first transmitted bit of the field, i.e., "Bit 0".
BIT 0 BIT N-1

N-BIT DATA FIELD
FIRST BIT TRANSMITTED = MSB

In accordance with modern data communications practice, spacecraft data fields are often
grouped into 8-bit "words" which conform to the above convention. Throughout this
Recommendation, the following nomenclature is used to describe this grouping:

8-BIT WORD = "OCTET"

By CCSDS convention, all "spare" bits shall be permanently set to value "zero". Note that
throughout this document, the word "Telecommand" may be abbreviated as "TC".
CCSDS 203.0-B-2 Page 1-2 June 2001
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
1.4 REFERENCES
[1] Telecommand Part 2—Data Routing Service. Recommendation for Space Data System
Standards, CCSDS 202.0-B-3. Blue Book. Issue 3. Washington, D.C.: CCSDS, June
2001.
[2] Telecommand Part 1—Channel Service. Recommendation for Space Data System
Standards, CCSDS 201.0-B-3. Blue Book. Issue 3. Washington, D.C.: CCSDS, June
2000.
[3] Packet Telemetry. Recommendation for Space Data System Standards, CCSDS 102.0-
B-5. Blue Book. Issue 5. Washington, D.C.: CCSDS, November 2000.
[4] Telemetry Channel Coding. Recommendation for Space Data System Standards,
CCSDS 101.0-B-5. Blue Book. Issue 5. Washington, D.C.: CCSDS, June 2001.
[5] Space Communications Protocol Specification (SCPS)—Network Protocol (SCPS-NP).
Recommendation for Space Data System Standards, CCSDS 713.0-B-1. Blue Book.
Issue 1. Washington, D.C.: CCSDS, May 1999.
[6] J. Postel. Internet Protocol. STD 5, September 1981. [RFC 791, RFC 950, RFC 919,
†
RFC 922, RFC 792, RFC 1112]
[7] S. Deering and R. Hinden. Internet Protocol, Version 6 (IPv6) Specification. RFC 1883,
December 1995.
The latest issues of these documents may be obtained from the CCSDS Secretariat at the
address indicated on page i.



† Internet Request for Comments (RFC) texts are available on line in various locations (e.g.,
http://ietf.org/rfc/); Internet standards are made up of one or more RFCs, which are identified in
square brackets following the entry.
CCSDS 203.0-B-2 Page 1-3 June 2001
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ISO 12174:2003(E)
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
2 TELECOMMAND DATA MANAGEMENT SERVICE OVERVIEW
A complete summary of the acronyms and terminology used internal to this document is
presented in Annex A, and a detailed specification of the services provided by each layer is
presented in Annex B.  The first-time reader should digest these Annexes before proceeding
further in this document.
Figure 2-1 illustrates the significance of the TC Data Management Service within the overall
Telecommand System, which contains three principal elements of service: Telecommand
Data Management Service; Telecommand Data Routing Service; and Telecommand Channel
Service. Each of these services is documented in separate Recommendations. A more
thorough discussion of the layered services, including expansion of Figure 2-1 in greater
detail, is contained in Reference [C2]. The Telecommand System is related to the Telemetry
System as documented in Reference [3] and Reference [4].
The TC Data Management Service enables user requests for command activity to be
generated, integrated, aggregated, translated and scheduled for delivery to the spacecraft by
drawing upon the Data Routing and Channel Services. The Data Management Service
contains three distinct layers of data handling operations:
(1) An APPLICATION PROCESS layer, which allows human users to control a
space mission by generating commands and supervising their delivery and
execution.
(2) A SYSTEM MANAGEMENT layer, which translates user command directives
into detailed command application data and delivery instructions, and which
manages their end-to-end delivery to the proper Application Process on the
spacecraft.
(3) A PACKETIZATION layer, which formats the command application data into
transportable telecommand data units and moves them to the spacecraft.
CCSDS 203.0-B-2 Page 2-1 June 2001
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE

APPLICATION PROCESS LAYER
COMMAND DIRECTIVE
TELECOMMAND,
PART 3: DATA
SYSTEM MANAGEMENT LAYER
MANAGEMENT SERVICE
TC APPLICATION DATA
PACKETIZATION LAYER
PACKET
SEGMENTATION LAYER
TELECOMMAND,
PART 2: DATA
SEGMENT
ROUTING SERVICE
TRANSFER LAYER
TRANSFER FRAME
CODING LAYER
TELECOMMAND,
CLTU
PART 1: CHANNEL
SERVICE
PHYSICAL LAYER
PHYSICAL WAVEFORM

Figure 2-1: Telecommand System
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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
NOTE A: Figure 2-1 represents a logical view of the TC System and physical
implementations may not necessarily correspond to the sequential flow of
operations implied by the figure.
NOTE B: This Recommendation primarily specifies the data structures and procedures
flowing ACROSS the layers from the sending to the receiving end of the
TC system, since these have a direct impact on the long lead-time design of
future spacecraft hardware and software. Comprehensive definition of the
associated operational protocols within each layer and the control
instructions, which are required to initialize the layers and to direct the flow
of TC data units BETWEEN the layers, remain items for potential future
extension of this document.
NOTE C: Inter-Agency cross-support gateways for telecommand are discussed in
Reference [C2].


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ISO 12174:2003(E)
CCSDS RECOMMENDATION FOR TELECOMMAND: DATA MANAGEMENT SERVICE
3 APPLICATION PROCESS LAYER: STANDARD DATA
STRUCTURES AND PROCEDURES
3.1 OVERVIEW OF THE LAYER
The service provided by the Application Process layer is to allow users to control remote
instruments or subsystems in space. The layer performs this service by providing its own
internal functions, and by drawing on services provided by the lower layers of the TC
System.  A functional overview of the Application Process layer is presented in Figure 3-1.
The sending end of the layer contains a large number of diverse Application Processes,
arranged to form a system which is used to superv
...