International ISO Standard ISO21177 Intelligent transport systems - Second edition ITs station security services for 2024-03 secure session establishment and authentication between trusted devices Systemes de transport intelligents - Services de sécurite d@ stations ITS pour I'etablissement et I'authentification des sessions securiseesentredispositifsdeconfiance Reference number IsO 21177:2024(en) @ ISO 2024 IS0 21177:2024(en) COPYRIGHT PROTECTED DOCUMENT IS02024 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 on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below orIso's memberbody inthe countryofthe requester. ISO copyright office CP 40i: Ch.de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +41 22 749 01 11 Email:copyright@iso.org Website: www.iso.org Published in Switzerland @ IS0 2024 - All rights reserved i