ISO 15893:2000

Space data and information transfer systems — Protocol specification for space communications — Transport protocol

Systèmes de transfert des informations et données spatiales — Spécification d'un protocole pour communications spatiales — Protocole de transport

General Information

• Status: Withdrawn
• Publication Date: 04-Oct-2000
• Withdrawal Date: 04-Oct-2000
• 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: 10-Sep-2010

Relations

• Revised: ISO 15893:2010 - Space data and information transfer systems — Space communications protocol specification (SCPS) — Transport protocol (SCPS-TP)
• Effective Date: 15-Apr-2008
• Consolidated By: ISO 14122-3:2001/Amd 1:2010 - Safety of machinery — Permanent means of access to machinery — Part 3: Stairs, stepladders and guard-rails — Amendment 1
• Effective Date: 06-Jun-2022

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 15893
First edition
2000-09-15
Space data and information transfer
systems — Protocol specification for space
communications — Transport protocol
Systèmes de transfert des informations et données spatiales —
Spécification d'un protocole pour communications spatiales — Protocole de
transport
Reference number
ISO 15893:2000(E)
©
ISO 2000

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ISO 15893:2000(E)
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ISO 15893:2000(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 3.
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 International Standard may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 15893 was prepared by the Consultative Committee for Space Data Systems (CCSDS)
(as CCSDS 714.0-B-1) and was adopted (without modifications except those stated in clause 3 of this International
Standard) by Technical Committee ISO/TC 20, Aircraft and space vehicles, Subcommittee SC 13, Space data and
information transfer systems.
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INTERNATIONAL STANDARD ISO 15893:2000(E)
Space data and information transfer systems — Protocol
specification for space communications — Transport protocol
1 Scope
This International Standard specifies the requirements for the services and protocols of the space communications
protocol specification (SCPS) transport service. These requirements are to allow independent implementations of
this protocol in space and ground segments of the SCPS network to interoperate.
This International Standard is applicable to any kind of space mission or infrastructure, regardless of complexity.
2 Conformance
This International Standard is applicable to all systems that claim conformance to the ISO/CCSDS SCPS transport
protocol.
3 Requirements
Requirements are the technical recommendations made in the following publication (reproduced on the following
pages), which is adopted as an International Standard:
CCSDS 714.0-B-1, May 1999, Recommendation for space data system standards — Space communications
protocol specification (SCPS) — Transport protocol (SCPS-TP).
For the purposes of international standardization, the modifications outlined below shall apply to the specific
clauses and paragraphs of publication CCSDS 714.0-B-1.
Pages i to v
This part is information which is relevant to the CCSDS publication only.
Page 1-8
Add the following information to the reference indicated in paragraph 1.8:
[10] Document CCSDS 713.0-B-1, May 1999, is equivalent to ISO 15891:2000.
[11] Document CCSDS 713.5-B-1, May 1999, is equivalent to ISO 15892:2000.
4 Revision of publication CCSDS 714.0-B-1
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 714.0-B-1. To this end, NASA
will act as a liaison body between CCSDS and ISO.
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ISO 15893:2000(E)
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ISO 15893:2000(E)
RECOMMENDATION FOR SPACE
DATA SYSTEM STANDARDS
SPACE COMMUNICATIONS
PROTOCOL SPECIFICATION (SCPS)—
TRANSPORT PROTOCOL
(SCPS-TP)
CCSDS 714.0-B-1
BLUE BOOK
May 1999
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ISO 15893:2000(E)
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
AUTHORITY
Issue: Blue Book, Issue 1
Date: May 1999
Location: Newport Beach, California, USA
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 reference [B1], 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 714.0-B-1 Page i May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
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
and are not considered binding on any Agency.
Recommendations
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 itself.
standard
-- 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 will be reviewed by
Recommendation
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 canceled.
In those instances when a new version of a Recommendation is issued, existing CCSDS-
related Agency standards and implementations are not negated or deemed to be non-CCSDS
compatible. It is the responsibility of each Agency to determine when such standards or
implementations are to be modified. Each Agency is, however, strongly encouraged to direct
planning for its new standards and implementations towards the later version of the
Recommendation.
CCSDS 714.0-B-1 Page ii May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
FOREWORD
Through the process of normal evolution, it is expected that expansion, deletion, or
modification of this document may occur. This Recommendation is therefore subject to
CCSDS document management and change control procedures as defined in reference [B1].
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 document should be addressed to the
CCSDS Secretariat at the address indicated on page i.
CCSDS 714.0-B-1 Page iii May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
At time of publication, the active Member and Observer Agencies of the CCSDS were
Member Agencies
– 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 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.
– Industry Canada/Communications Research Centre (CRC)/Canada.
– 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 714.0-B-1 Page iv May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
DOCUMENT CONTROL
Document Title Date Status
CCSDS Space Communications May 1999 Original issue
714.0-B-1 Protocol Specification
(SCPS)—Transport
Protocol (SCPS-TP)
CCSDS 714.0-B-1 Page v May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
CONTENTS
Section Page
1 INTRODUCTION.1-1
1.1 PURPOSE .1-1
1.2 SCOPE .1-1
1.3 APPLICABILITY.1-1
1.4 RATIONALE.1-1
1.5 ORGANIZATION OF THIS RECOMMENDATION.1-1
1.6 HOW TO READ THIS DOCUMENT .1-2
1.7 CONVENTIONS AND DEFINITIONS.1-3
1.8 REFERENCES.1-7
2 OVERVIEW .2-1
3 SCPS-TP EXTENSIONS TO STANDARD TCP.3-1
3.1 RELATIONSHIP BETWEEN SCPS-TP AND TCP.3-1
3.2 CONNECTION MANAGEMENT.3-1
3.3 DATA TRANSFER .3-5
3.4 ERROR RECOVERY.3-11
3.5 SELECTIVE NEGATIVE ACKNOWLEDGMENT OPTION.3-14
3.6 SCPS-TP HEADER COMPRESSION .3-20
3.7 MULTIPLE TRANSMISSIONS FOR FORWARD ERROR CORRECTION.3-26
4 USER DATAGRAM PROTOCOL EXTENSION.4-1
5 MANAGEMENT INFORMATION BASE (MIB) REQUIREMENTS.5-1
5.1 TYPES OF MANAGEMENT INFORMATION.5-1
5.2 MIB REQUIREMENTS FOR ROUTE-SPECIFIC INFORMATION.5-1
5.3 MIB REQUIREMENTS FOR SCPS TRANSMISSION CONTROL PROTOCOL .5-5
5.4 MIB REQUIREMENTS FOR SCPS USER DATAGRAM PROTOCOL.5-7
6 CONFORMANCE REQUIREMENTS.6-1
6.1 GENERAL REQUIREMENTS .6-1
6.2 TRANSMISSION CONTROL PROTOCOL REQUIREMENTS .6-1
6.3 USER DATAGRAM PROTOCOL REQUIREMENTS .6-12
6.4 NETWORK MANAGEMENT REQUIREMENTS.6-13
ANNEX A SYMBOLS AND ABBREVIATIONS.A-1
ANNEX B INFORMATIVE REFERENCES . B-1
ANNEX C PROTOCOL IMPLEMENTATION CONFORMANCE
STATEMENT PROFORMA .C-1
ANNEX D SERVICES OF THE TRANSPORT PROTOCOL .D-1
CCSDS 714.0-B-1 Page vi May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
CONTENTS (continued)
Figure Page
3-1 SCPS Capabilities Option .3-3
3-2 Out-of-Sequence Queue for SNACK Example.3-18
3-3 SNACK Option Resulting from Out-of-Sequence Queue Example .3-18
3-4 SNACK Options (without SNACK Bit-Vector) Resulting from
Out-of-Sequence Queue Example.3-19
3-5 Compressed SCPS-TP Header .3-24
D-1 SCPS-TP Composite Service Diagram for Connection-Oriented Services .D-22
D-2 Local Service Provider State Diagram.D-23
D-3 Composite SCPS-TP Service State Diagram for Connection-Oriented
Types of Service.D-24
D-4 State Diagram for Unacknowledged Service .D-25
Table
1-1 Values of the N-User_Internet_Protocol_Number Parameter Used by SCPS-TP.1-6
3-1 SCPS Capabilities Option Bit-Vector Contents.3-4
3-2 Compressed Header Bit-Vector Contents .3-21
D-1 SCPS-TP Services and Types of Service .D-2
D-2 SCPS-TP Data Transport Characteristics.D-4
D-3 Specific SCPS-TP Data Transfer Capabilities .D-6
D-4 SCPS-TP Service Request Primitives .D-7
D-5 SCPS-TP Service Confirm and Indication Primitives .D-15
CCSDS 714.0-B-1 Page vii May 1999
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ISO 15893:2000(E)
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
1 INTRODUCTION
1.1 PURPOSE
The purpose of this Recommendation is to define the services and protocols that provide the
Space Communications Protocol Specification (SCPS) Transport service. This definition
will allow independent implementations of the protocols in the space and ground segments of
the SCPS Network to interoperate.
1.2 SCOPE
This Recommendation is intended to be applied to all systems that claim conformance to the
SCPS Transport protocols.
1.3 APPLICABILITY
This Recommendation is designed to be applicable to any kind of space mission or
infrastructure, regardless of complexity. It is intended that this Recommendation become a
uniform standard among all CCSDS Agencies.
1.4 RATIONALE
The CCSDS believes it is important to document the rationale underlying the
recommendations chosen, so that future evaluations of proposed changes or improvements
will not lose sight of previous decisions. The concept and rationale for SCPS-TP may be
found in reference [B2].
1.5 ORGANIZATION OF THIS RECOMMENDATION
This Recommendation contains six sections and four annexes. This section presents
introductory material that establishes the context for the remainder of the document. Section
2 contains an overview of the protocols, summarizing the main technical requirements and
describing the approach used to provide the protocols’ services. Sections 3 and 4 present the
specifications for Transmission Control Protocol (TCP) and User Datagram Protocol (UDP)
in the SCPS environment. Section 5 establishes the requirements for maintaining
management information. Section 6 presents conformance requirements for implementations.
The four annexes to this Recommendation provide supporting information. Some of the
annexes contain normative material, while some contain informative material. Annex A is
informative and contains the acronyms and abbreviations used commonly throughout the
document. Annex B is informative and contains the informative references cited throughout
the document. Annex C is normative and contains the proforma for the Protocol
Implementation Conformance Statement (PICS). The PICS unambiguously describes the
capabilities provided by an implementation of the protocol. Annex D is normative and
contains the service specification.
CCSDS 714.0-B-1 Page 1-1 May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
1.6 HOW TO READ THIS DOCUMENT
This document makes modifications and extensions to TCP and UDP for use in spacecraft
communications environments, characterized by potentially long delays, unbalanced
forward- and return-link data rates, and potentially high error rates. It is anticipated that
some readers of this document will be protocol implementers, probably with TCP
implementation experience. Other readers will be individuals more familiar with the
particular application environment than with the protocols.
For readers and implementers already familiar with the internals of TCP and UDP, this
document may best be used in the following manner:
1) Review section 6 of this document. It describes the implementation requirements for
TCP and UDP, and gives an indication of those capabilities within TCP and UDP that
have been modified (indicated by text to the effect ‘as amended by a.b.c of this
document’, where a.b.c is a section reference in this document).
Also in section 6 is a list of mission-specific capabilities that, depending on the needs
of the mission, may be beneficial to add to the basic functionality of the protocols.
Section 6 provides an introduction to these capabilities, and pointers back to sections
3 and 4, in which the capabilities are specified. Readers should use section 6 as a
means of identifying the capability set required for their mission(s).
Some of the capabilities required for a mission depend on the availability of other
capabilities. These dependencies, along with a restatement of the implementation
requirements, are documented in table form in the Protocol Implementation
Conformance Statement that appears in annex C. Annex C specifies the format in
which an implementer must document the details of his or her implementation.
2) Review sections 3 and 4, which specify SCPS-TP-unique options and modifications
for TCP and UDP.
3) Review section 5, which identifies the management information requirements.
For readers and implementers who are generally familiar with the operation of TCP and
UDP, but not the internals of the protocols, the following approach to reviewing this
document may be useful:
1) Read over the UDP and TCP RFCs. The UDP specification is quite short (3 pages).
The TCP specification is significantly longer, but also provides a substantial amount
of background information. These documents were written in 1980 and 1981,
respectively.
2) Read section 4 of RFC 1122. This document captures the ‘lessons learned’ from
using TCP and UDP as of 1989. In addition to placing requirements on
implementations of TCP and UDP, it provides a significant amount of explanatory
information and discussion about rationale for particular requirements. RFC 1122
CCSDS 714.0-B-1 Page 1-2 May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
constitutes an extension to the base TCP and UDP specifications, in addition to
describing implementation requirements.
3) Read over section 6 of this document. It refers to the TCP and UDP RFCs and to
RFC 1122, and either endorses or revises the requirements put forward in RFC 1122.
Read the ‘Mission-Specific Capabilities’ subsection, and identify whether any of
these capabilities are necessary. If so, review the references identified in each of the
mission-specific capability sections.
4) Finally, read sections 3 through 5.
Readers with little previous familiarity with TCP or UDP should consider reviewing an
introductory text on the subject. One excellent example is TCP/IP Illustrated, Volume 1, by
W. Richard Stevens (Copyright 1994, Addison-Wesley Professional Computing Series).
Chapters 1, 11, and 17-24 are particularly relevant. Note that additional information about
one of the mission-specific capabilities—the modifications to TCP to support Transactions—
is presented in Chapters 1-12 of TCP/IP Illustrated, Volume 3, by W. Richard Stevens
(Copyright 1996, Addison-Wesley Professional Computing Series).
1.7 CONVENTIONS AND DEFINITIONS
1.7.1 OCTET NUMBERING CONVENTION AND NOMENCLATURE
This document does not deal with transmission of any data elements smaller than one octet.
As such, the transmission order of bits within an octet is an issue to be dealt with at lower
layers. However, the relative ordering of octets within a word and the unambiguous
numbering of bits within an octet are relevant here. The order in which multi-octet fields
defined in this document are submitted for transmission is called ‘Big Endian’ byte ordering.
When applied to networking, it is called ‘network byte order’. In this ordering scheme, bit 0
of a 32-bit value is the most significant bit; bit 31 is the least significant bit. The octet
containing bits 0-7 is transmitted first, followed by the octet containing bits 8-15, followed
by the octet containing bits 16-23, and finally the octet containing bits 24-31. Note that ‘Big
Endian’ byte ordering is NOT what some machines (notably the 80x86 class of machines)
use internally. Implementers must ensure that headers are converted to network byte order
for transmission.
The following conventions apply throughout this Recommendation:
a) the words ‘shall’ and ‘must’ imply a binding and verifiable specification;
b) the word ‘should’ implies an optional, but desirable, specification;
c) the word ‘may’ implies an optional specification;
d) the words ‘is’, ‘are’, and ‘will’ imply statements of fact.
CCSDS 714.0-B-1 Page 1-3 May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
1.7.2 DEFINITIONS
Address Family: An address family specifies the structural rules required to interpret the
internal fields of an address. The SCPS Network supports three address families: the SCPS
address family, the Internet Protocol (IP) address family, and the Internet Protocol version
Six (IPv6) address family.
Address Type: An address type defines the meaning that the addresses have (that is, whether
they identify end systems or a path between end systems), the number of addresses that
appear in a SCPS Network Protocol header (two addresses if the addresses identify end
systems, only one if the address identifies a path between end systems), and the address
family that is valid for the addresses.
Connection: A connection is defined by information that is named, persistent, and shared
across the systems supporting an instance of communication. For transport protocols, these
systems are the endpoints that terminate the transport protocol, but not intermediate systems.
End System: An addressable network entity within the SCPS Network.
Extended End System Address: The Extended End System Address identifies a single end
system or an end-system group. The Extended End System Address conforms to the
structural rules of either the SCPS Address Family or the IP Address Family. Extended End
System Addresses may be parameters to the primitives of the Unit Data service.
Gateway: A network-addressable system that terminates a protocol at a given layer and
invokes similar services at the same layer of an adjacent network.
Host: A network-addressable system that may send or receive network-layer packets, but
does not forward packets.
Internet Protocol Number: The Internet Protocol Number is the transport protocol
identifier used by Internet Protocols. Values may range from 0 through 255, and valid values
are defined in reference [1].
IP Address Family: The IP Address Family specifies a set of structural rules for the
interpretation of Extended End System Addresses, and is defined in reference [1], and the
possible formats are refined in section 3.2.1.3 of RFC 1122 (reference [2]).
Maximum Segment Size: The maximum amount of user data that can be carried in a
Segment. This value is calculated by subtracting the size of the network, security, and
transport layer headers from the MTU size.
Maximum Transmission Unit: The Maximum Transmission Unit (MTU) specifies the
maximum amount of data that the subnetwork layer will accept in a single subnetwork
service request. The MTU for a route is the minimum of all known MTUs along that route.
CCSDS 714.0-B-1 Page 1-4 May 1999
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ISO 15893:2000(E)
CCSDS RECOMMENDATION FOR SCPS TRANSPORT PROTOCOL (SCPS-TP)
NOTE – It is anticipated that this value will be known and managed as part of the routing
table information; however, techniques for dynamically discovering the MTU of
a route exist. Refer to RFC 1191, ‘Path MTU Discovery’ (reference [B3]) for
more information.
N-Address: an address in the SCPS Network. The attributes of an N-Address are the
Address Type and the Address Family.
N-Basic_Quality_of_Service parameter: The Basic Quality of Service (QOS) parameter of
the N-UNITDATA service primitives
...