ISO/IEC 13888-3:2020

INTERNATIONAL ISO/IEC
STANDARD 13888-3
Third edition
2020-09
Information security — Non-
repudiation —
Part 3:
Mechanisms using asymmetric
techniques
Sécurité de l'information — Non-répudiation —
Partie 3: Mécanismes utilisant des techniques asymétriques
Reference number
©
ISO/IEC 2020
© ISO/IEC 2020
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ii © ISO/IEC 2020 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 2
5 Requirements . 3
6 Trusted third party involvement . 3
7 Digital signatures . 4
8 Use of non-repudiation tokens with and without delivery authorities .4
9 Evidence produced by the end entities . 5
9.1 General . 5
9.2 Non-repudiation of origin . 5
9.2.1 Non-repudiation of origin token . 5
9.2.2 Mechanism for non-repudiation of origin . 6
9.3 Non-repudiation of delivery . 6
9.3.1 Non-repudiation of delivery token . 6
9.3.2 Mechanism for non-repudiation for delivery . 7
10 Evidence produced by a delivery authority . 8
10.1 General . 8
10.2 Non-repudiation of submission . 8
10.2.1 Non-repudiation of submission token . 8
10.2.2 Mechanism for non-repudiation of submission . 9
10.3 Non-repudiation of transport. 9
10.3.1 Non-repudiation of transport token . 9
10.3.2 Mechanism for non-repudiation of transport .10
11 Mechanisms to ensure that an NRT was signed before a time t .11
11.1 General .11
11.2 Mechanism using a time-stamping service .11
11.3 Mechanism using a time-marking service .11
Bibliography .13
© ISO/IEC 2020 – All rights reserved iii

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that
are members of ISO or IEC participate in the development of International Standards through
technical committees established by the respective organization to deal with particular fields of
technical activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non-governmental, in liaison with ISO and IEC, also
take part in the work.
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 document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (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 and IEC 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) or the IEC
list of patent declarations received (see http:// patents .iec .ch).
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 Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 27, Information security, cybersecurity and privacy protection.
This third edition cancels and replaces the second edition (ISO/IEC 13888-3:2009), which has been
technically revised.
The main changes compared to the previous edition are as follows:
— Clause 3 has been clarified;
— the terminology and notation issues have been fixed;
— a requirement has been changed into a recommendation in Clause 7; and
— a new requirement has been introduced in Clause 5.
A list of all parts in the ISO/IEC 13888 series can be found on the ISO website.
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.
iv © ISO/IEC 2020 – All rights reserved

Introduction
The goal of the non-repudiation service is to generate, collect, maintain, make available and validate
evidence concerning a claimed event or action in order to resolve disputes about the occurrence or non-
occurrence of the event or action.
Such evidence can be produced either directly by an end entity or by a trusted third party.
This document only addresses the following non-repudiation services:
— non-repudiation of origin;
— non-repudiation of delivery;
— non-repudiation of submission;
— non-repudiation of transport.
Non-repudiation mechanisms involve the exchange of non-repudiation tokens specific for each non-
repudiation service. The non-repudiation mechanisms defined in this document consist of digital
signatures and additional data. Non-repudiation tokens are stored as non-repudiation information and
are used subsequently in the event of disputes.
Additional information is required to complete the non-repudiation token. Depending on the non-
repudiation policy in effect for a specific application and the legal environment within which the
application operates, that additional information takes one of the following two forms:
— information provided by a time-stamping authority which provides assurance that the signature of
the non-repudiation token was created before a given time;
— information provided by a time-marking service which provides assurance that the signature of the
non-repudiation token was recorded before a given time.
Non-repudiation can only be provided within the context of a clearly defined security policy for
a particular application and its legal environment. Non-repudiation policies are described in
ISO/IEC 10181-4.
© ISO/IEC 2020 – All rights reserved v

INTERNATIONAL STANDARD ISO/IEC 13888-3:2020(E)
Information security — Non-repudiation —
Part 3:
Mechanisms using asymmetric techniques
1 Scope
This document specifies mechanisms for the provision of specific, communication-related,
non-repudiation services using asymmetric cryptographic techniques.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 9796 (all parts), Information technology — Security techniques — Digital signature schemes
giving message recovery
ISO/IEC 13888-1, Information technology — Security techniques — Non-repudiation — Part 1: General
ISO/IEC 14888 (all parts), IT Security techniques — Digital signatures with appendix
ISO/IEC 18014-1, Information technology — Security techniques — Time-stamping services — Part 1:
Framework
ISO/IEC 29192-4, Information technology — Security techniques — Lightweight cryptography — Part 4:
Mechanisms using asymmetric techniques
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 13888-1 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
time-marking service
service providing evidence that a hash code together with an identifier of a hash-function have been
recorded before a certain point in time
3.2
time-stamping service
service providing evidence that a data item existed before a certain point in time
© ISO/IEC 2020 – All rights reserved 1

4 Symbols
A claimed message originator
B message recipient or the intended message recipient
C Trusted third party
D ith delivery authority, a trusted third party (1≤i≤n, where n is the number of
i
delivery authorities in the system)
f data term (flag) indicating the type of non-repudiation service in effect (i ∊{ori-
i
gin, delivery, submission, transport})
ID , ID , ID , ID distinguishing identifiers of the entities A, B, C and D
A B C D i
i
Imp(y) imprint of data y, consisting of either y or the hash-code of y together with an
identifier of the hash-function being used
m message which is sent from entity A to entity B in respect of which non-repudia-
tion services are provided
NRDT non-repudiation of delivery token
NROT non-repudiation of origin token
NRST non-repudiation of submission token
NRTT non-repudiation of transport token
Pol distinguishing identifier of the non-repudiation policy (or policies) which applies
(apply) to the evidence
Q optional data item that may contain additional information, e.g., the
distinguishing identifiers of the message m, signature mechanism, or
hash-function
SIG (m) signed message generated on data m by entity X using its private key
X
T date and time that the i th type of event or action took pl
...