IEC IEC 63448 Edition 1.02025-11 INTERNATIONAL STANDARD Lowand ultra-lowlatencycommunicationandcontrolsystems IEC 63448:2025-11(en) ICS 33.160.60 ISBN 978-2-8327-0816-3 THIS PUBLICATIONIS COPYRIGHTPROTECTED Copyright@2025IEC,Geneva,Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanicai, including photocopying and microfilm, without permission in writing from either IEc or IEC's member National Committee in the country of the requester. If you have any questions about IEC copyright IEC member National Committee for further information. IEC Secretariat Tel.: +41 22 919 02 11 3, rue de Varembe [email protected] CH-1211 Geneva 20 www.iec.ch Switzerland About the IEC International Standards for all electrical, electronic and related technologies. About IEC publications The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the IECpublicationssearch- IEc Products &Services Portal-products.iec.ch webstore.iec.ch/advsearchform Discover our powerful search engine and read freely all the The advanced search enables to find IEC publications by a publications previews, graphical symbols and the glossary. variety of criteria (reference number, text, technical With a subscription you wili always have access to up to date committee, ...). It also gives information on projects, content tailored to your needs. replaced and withdrawn publications. Electropedia -www.electropedia.org IEc Just Published-webstore.iec.ch/justpublished Stay up to date on all new IEC publications. Just Published containing more than 22 500 terminological entries in English details all new publications released. Available online and and French, with equivalent terms in 25 additional languages. once a month by email. Also known as the International Electrotechnical Vocabulary (IEV) online. IECCustomerServiceCentre-webstore.iec.ch/csc If you wish to give us your feedback on this publication or need further assistance, please contact the Customer Service Centre:[email protected]. Warning! Make sure that you obtained this publication from an authorized distributor. IEC63448:2025@IEC2025 CONTENTS FOREWORD 4 INTRODUCTION. 1 Scope.. 2 Normativereferences 3 Terms and definitions. 3.1 Terms and definitions... 3.2 Abbreviated terms.... 4 General. .10 5 System-level design aspects of ULCcs technology 5.1 ExamplesofPHYlayersforULCCS .12 5.2 MAC layer aspects.. 12 5.3 Managementaspects 13 6 Medium access control (MAC) layer... 6.1 General MACframework .13 6.2 Frame formats. 14 6.2.1 General... 14 6.2.2 Signaling frame... .14 6.2.3 Downlink frame. .15 6.2.4 .15 Uplink frame.. 6.2.5 Retransmission frame. 15 6.2.6 Slot structure. 15 6.3 Message types 15 6.4 Message structure. 15 6.5 MACfunctions. 18 6.5.1 General... ..18 6.5.2 Schedule generation 6.5.3 Data transmissions.. ..21 6.5.4 Retransmission handling.. 6.5.5 Frequency hopping .25 6.6 MAC parameters.. .25 6.7 Logical channels.. .26 7 .28 7.1 Time synchronization .28 7.1.1 General... .28 7.1.2 Multi-hop time synchronization based on synchronous flooding.. .28 7.1.3 Multi-hop time synchronization based on timestamping ..29 7.1.4 Single-hop time synchronization based on IEEE 802.11-2012... ....30 7.2 Multi-hop operation... 7.2.1 General......... 7.2.2 ...31 7.2.3 Topology generation by the MAC layer. ..32 7.3 Parallel operation of multiple domains.. .33 7.3.1 ..33 7.3.2 Synchronous operation of multiple domains.. .33 7.3.3 Asynchronousoperationofmultipledomains .34 7.4 Parallel operation over multiple radios .35 IEC63448:2025@IEC2025 7.5 Security. ..35 Annex A(informative)Use-cases and reference scenarios.. A.1 Use-case 1:Multi-sensory wirelessteleoperation.. .37 A.2 Use-case 2: Multi-user VR environment .37 A.3 ULCCSoperationoverBluetooth?5.0PHYlayers .38 Bibliography. .40 Figure 1-System model formultimedia-centric communication and control in local environments .10