ISO/IEC INTERNATIONAL STANDARD 19592-1 First edition 2016-11-15 Information technology Security techniques Secret sharing Part 1: General Technologies de Il'information -Techniques de securite-Partage de secret- Partie1:Général Reference number IS0/IEC 19592-1:2016(E) IEC IS0/IEC2016 IS0/IEC19592-1:2016(E) COPYRIGHTPROTECTEDDOCUMENT IS0/IEC2016,Published in Switzerland All rights reserved. Unless otherwise specified, 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 or Iso's member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org ii IS0/IEC2016-Allrightsreserved IS0/IEC19592-1:2016(E) Contents Page Foreword iv Introduction ..V 1 Scope. .1 2 Normative references .1 3 Terms and definitions .1 4 General model of secret sharing .2 4.1 Parties involved. .2 4.2 Parameters. 3 4.2.1 Overview 3 4.2.2 Message space 3 4.2.3 Share space. 3 4.2.4 Number of shares .3 4.2.5 Access structure .3 4.3 Message sharing process .4 4.4 Messagereconstructionprocess 4 5 Properties of secret sharing schemes .5 5.1 Fundamental requirements .5 5.1.1 Overview .5 5.1.2 Message confidentiality .6 5.1.3 Message recoverability .6 5.2 Optional requirements. 6 5.2.1 Overview. .6 5.2.2 Homomorphicity .6 5.2.3 Verifiability .6 5.3 Otherproperties 7 7 5.3.1 Overview 5.3.2 Confidentiality guarantees 7 5.3.3 Complexity 7 5.3.4 Information rate 7 IS0/IEC2016-Allrightsreserved ii