ISO INTERNATIONAL STANDARD 18441 Third edition 2021-06 Space data and information transfer systems Space link extension - Application program interface for transfer services Core specification Systemes de transfert des informations et données spatiales- Extension de liaisons spatiales-Interface duprogramme d'application pour les services de transfertSpécification de base Reference number IS0 18441:2021(E) ISO ISO2021 IS0 18441:2021(E) COPYRIGHTPROTECTEDDOCUMENT @IS02021 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting below or Iso's member body in the country of the requester. IsO copyrightoffice CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +41 22 749 01 11 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2021 - All rights reserved IS0 18441:2021(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. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of IsO documents should be noted (see www.iso.org/directives). 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. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the Iso list of patent declarations received (see www.iso.org/patents) Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation of the voluntary nature of standards, the meaning of Iso specific terms and expressions related to conformity assessment, as well as information about Iso's adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www.iso.org/iso/foreword.html. This document was prepared by the Consultative Committee for Space Data Systems (CCsDS) (as CCSDS 914.0-M-2 Cor.1, 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 (IS0 18441:2016), which has been technically revised. The main changes compared to the previous edition are as follows: references CcSDs 913.1-B for one-way hash function algorithm and removes reference to Secure Hash Algorithm standard. 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 @ IS0 2021 - All rights reserved iii IS0 18441:2021(E) APIFORSLETRANSFERSERVICESCORESPECIFICATION CONTENTS Section Page INTRODUCTION.. .. 1-1 1.1 PURPOSE OF THIS RECOMMENDED PRACTICE 1.2 SCOPE.. 1-1 1.3 APPLICABILITY -2 1.4 RATIONALE.. -3 1.5 DOCUMENT STRUCTURE 1-4 1.6 1.7 REFERENCES 1-10 2 DESCRIPTION OF THE SLE API. .2-1 2.1 INTRODUCTION ,2-1 2.2 SPECIFICATION METHOD AND NOTATION. .2-2 2.3 LOGICAL VIEW .. ..2-7 2.4 SECURITY ASPECTS OF CORE SLE API CAPABILITIES. 3 SPECIFICATI