ISO INTERNATIONAL STANDARD 4426 First edition 2021-07 Intelligent transport systems Lower layer protocols for usage in the European digital tachograph Systemes de transport intelligents - Protocoles de couche basse pour utilisation dans le cadre du chrono tachygraphe numerique européen Reference number IS0 4426:2021(E) ISO ISO2021 IS0 4426:2021(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