ISO 26143:2021

INTERNATIONAL ISO
STANDARD 26143
Third edition
2021-06
Space data and information transfer
systems — Space link extension (SLE)
— Return operational control fields
service specification
Systèmes de transfert des données et informations spatiales —
Extension de liaisons spatiales (SLE) — Service des champs de
contrôle de retour opérationnel
Reference number
©
ISO 2021
© ISO 2021
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Foreword
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This document was prepared by the Consultative Committee for Space Data Systems (CCSDS) (as CCSDS
911.5-B-3, August 2016) and was adopted (without modifications) by Technical Committee ISO/TC 20,
Space vehicles, Subcommittee SC 13, Space data and information transfer systems.
This third edition cancels and replaces the second edition (ISO 26143:2013), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— adds clarifications and corrections;
— adds production status annex.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
CCSDS RECOMMENDED STANDARD FOR SLE ROCF SERVICE
CONTENTS
Section Page
1 INTRODUCTION . 1-1
1.1 PURPOSE OF THIS RECOMMENDED STANDARD . 1-1
1.2 SCOPE . 1-1
1.3 APPLICABILITY . 1-2
1.4 RATIONALE . 1-2
1.5 DOCUMENT STRUCTURE . 1-2
1.6 DEFINITIONS, NOMENCLATURE, AND CONVENTIONS . 1-5
1.7 REFERENCES . 1-14
2 DESCRIPTION OF THE ROCF SERVICE . 2-1
2.1 OVERVIEW . 2-1
2.2 SPACE LINK EXTENSION REFERENCE MODEL . 2-2
2.3 SERVICE MANAGEMENT . 2-3
2.4 ARCHITECTURE MODEL—FUNCTIONAL VIEW . 2-4
2.5 ARCHITECTURE MODEL—CROSS SUPPORT VIEW . 2-7
2.6 FUNCTIONAL DESCRIPTION . 2-8
2.7 OPERATIONAL SCENARIO . 2-18
2.8 SECURITY ASPECTS OF THE SLE ROCF TRANSFER SERVICE . 2-19
3 ROCF SERVICE OPERATIONS . 3-1
3.1 GENERAL CONSIDERATIONS . 3-1
3.2 ROCF-BIND . 3-15
3.3 ROCF-UNBIND . 3-22
3.4 ROCF-START . 3-26
3.5 ROCF-STOP . 3-34
3.6 ROCF-TRANSFER-DATA . 3-36
3.7 ROCF-SYNC-NOTIFY . 3-40
3.8 ROCF-SCHEDULE-STATUS-REPORT . 3-44
3.9 ROCF-STATUS-REPORT . 3-48
3.10 ROCF-GET-PARAMETER . 3-51
3.11 ROCF-PEER-ABORT . 3-56
4 ROCF PROTOCOL . 4-1
4.1 GENERIC PROTOCOL CHARACTERISTICS . 4-1
4.2 ROCF SERVICE PROVIDER BEHAVIOR . 4-4
CCSDS 911.5-B-3 Page vi August 2016
CCSDS RECOMMENDED STANDARD FOR SLE ROCF SERVICE
CONTENTS (continued)
Section Page
ANNEX A DATA TYPE DEFINITIONS (NORMATIVE) . A-1
ANNEX B PRODUCTION STATUS (NORMATIVE) .B-1
ANNEX C CONFORMANCE MATRIX (NORMATIVE) . C-1
ANNEX D INDEX TO DEFINITIONS (INFORMATIVE) . D-1
ANNEX E ACRONYMS (INFORMATIVE) .E-1
ANNEX F INFORMATIVE REFERENCES (INFORMATIVE) . F-1
Figure
1-1 SLE Services Documentation . 1-4
2-1 Return Frame Processing SLE-FG . 2-4
2-2 ROCF Service Production and Provision . 2-7
2-3 Example of the Management and Provision of ROCF Service . 2-8
2-4 Simplified ROCF Service Provider State Transition Diagram . 2-11
2-5 Communications Realization of ROCF Service . 2-13
2-6 Buffers and Delivery Modes . 2-18
B-1 ROCF Production Status Transitions .B-1

Table
2-1 ROCF Operations . 2-9
3-1 Setting of ROCF Service Configuration Parameters . 3-6
3-2 ROCF-BIND Parameters . 3-16
3-3 ROCF-UNBIND Parameters . 3-23
3-4 ROCF-START Parameters . 3-27
3-5 ROCF-STOP Parameters . 3-34
3-6 ROCF-TRANSFER-DATA Parameters . 3-36
3-7 ROCF-SYNC-NOTIFY Parameters . 3-40
3-8 ROCF-SCHEDULE-STATUS-REPORT Parameters . 3-45
3-9 ROCF-STATUS-REPORT Parameters . 3-48
3-10 ROCF-GET-PARAMETER Parameters . 3-51
3-11 ROCF Parameters . 3-53
3-12 ROCF-PEER-ABORT Parameters . 3-56
4-1 Provider Behavior . 4-6
4-2 Event Description References . 4-12
4-3 Predicate Descriptions . 4-12
4-4 Boolean Flags . 4-13
4-5 Compound Action Definitions . 4-13
B-1 Production Status Changes and Notifications .B-2
B-2 Effect of Production Status on Operations .B-3
C-1 Conformance Matrix for ROCF Service (Operations) .C-1
C-2 Conformance Matrix for ROCF Service (Other Requirements) .C-2
CCSDS 911.5-B-3 Page vii August 2016
CCSDS RECOMMENDED STANDARD FOR SLE ROCF SERVICE
1 INTRODUCTION
1.1 PURPOSE OF THIS RECOMMENDED STANDARD
The purpose of this Recommended Standard is to define the Space Link Extension (SLE)
Return Operational Control Fields (ROCF) service in conformance with the SLE Reference
Model (reference [1]). The ROCF service is an SLE transfer service that delivers to a
mission user all operational control fields from one master channel or one virtual channel.
NOTE – Reference [1] defines the Return Master Channel Operational Control Field (Rtn
MC-OCF) service and the Return Virtual Channel Operational Control Field (Rtn
VC-OCF) service as two distinct services. Subsequent study has indicated that it
is preferable to define one service that provides the functionality of both. The
ROCF service defined here does just that. It is anticipated that a future issue of
reference [1] will take the same approach, deleting the Rtn MC-OCF and Rtn
VC-OCF services and replacing them with the Rtn OCF service.
1.2 SCOPE
This Recommended Standard defines, in an abstract manner, the ROCF service in terms of:
a) the operations necessary to provide the service;
b) the parameter data associated with each operation;
c) the behaviors that result from the invocation of each operation; and
d) the relationship between, and the valid sequence of, the operations and resulting
behaviors.
It does not specify:
a) individual implementations or products;
b) the implementation of entities or interfaces within real systems;
c) the methods or technologies required to acquire telemetry frames from signals
received from a spacecraft;
d) the methods or technologies required to provide a suitable environment for
communications; or
e) the management activities required to schedule, configure, and control the ROCF
service.
CCSDS 911.5-B-3 Page 1-1 August 2016
CCSDS RECOMMENDED STANDARD FOR SLE ROCF SERVICE
1.3 APPLICABILITY
1.3.1 APPLICABILITY OF THIS RECOMMENDED STANDARD
This Recommended Standard provides a basis for the development of real systems that
implement the ROCF service. Implementation of the ROCF service in a real system
additionally requires the availability of a communications service to convey invocations and
returns of ROCF service operations between ROCF service users and providers. This
Recommended Standard requires that such a communications service must ensure that
invocations and returns of operations are transferred:
a) in sequence;
b) completely and with integrity;
c) without duplication;
d) with flow control that notifies the application layer in the event of congestion; and
e) with notification to the application layer in the event that communications between
the ROCF service user and the ROCF service provider are disrupted, possibly
resulting in a loss of data.
It is the specific intent of this Recommended Standard to define the ROCF service in a
manner that is independent of any particular communications services, pro
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