ISO/IEC 20944-2:2013

INTERNATIONAL ISO/IEC
STANDARD 20944-2
First edition
2013-01-15
Information technology — Metadata
Registries Interoperability and Bindings
(MDR-IB) —
Part 2:
Coding bindings
Technologies de l'information — Interopérabilité et liaisons des registres
de métadonnées (MDR-IB) —
Partie 2: Liaisons de codage
Reference number
©
ISO/IEC 2013
©  ISO/IEC 2013
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ii © ISO/IEC 2013 – All rights reserved

Contents Page
Foreword . iv
Introduction . v
1  Scope . 1
2  Normative references . 1
3  Terms and definitions . 1
4  Intended use of this part of ISO/IEC 20944 . 1
5  Abstract model . 2
5.1  Overview of data objects . 2
5.2  Referenced data interchange specification . 2
5.3  Data structuring model . 3
5.4  Designations, identifiers, and navigation . 4
6  Semantics . 6
6.1  Datatypes . 6
6.2  Inherent structure . 6
6.3  Hierarchical naming . 6
6.4  Associated properties . 7
6.5  Merged navigation identifiers for properties . 8
6.6  External, logical, and internal naming conventions . 8
6.7  The _value property . 9
6.8  Keywords . 9
7  Bindings . 9
8  Administration . 9
8.1  Use of registry-defined datatypes . 9
9  Conformance . 10
9.1  Coding conformance paradigm . 10
9.2  Data instance conformance . 10
9.3  Data application conformance . 10
9.4  Conformance labels . 12
10  Reserved for future standardization . 12
11  Dotted Identifier Value Pair (DIVP) coding binding . 12
11.1  General . 12
11.2  Generating and producing DIVP . 14
11.3  Consuming and interpreting DIVP . 16
11.4  Representation of basic data types . 17
11.5  Encoding of character representations . 19
11.6  Handling exceptions and extensions . 19
11.7  Conformance label prefix . 20
12  XML coding binding . 20
12.1  General . 20
12.2  Generating and producing XML . 20
12.3  Consuming and interpreting XML . 23
12.4  Representation of basic data types . 24
12.5  Encoding of character representations . 27
12.6  Handling exceptions and extensions . 27
12.7  Conformance label prefix . 27
Bibliography . 28

© ISO/IEC 2013 – 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. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
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.
ISO/IEC 20944-2 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 32, Data management and interchange.
ISO/IEC 20944 consists of the following parts, under the general title Information technology — Metadata
Registries Interoperability and Bindings (MDR-IB):
 Part 1: Framework, common vocabulary, and common provisions for conformance
 Part 2: Coding bindings
 Part 3: API bindings
 Part 4: Protocol bindings
 Part 5: Profiles
iv © ISO/IEC 2013 – All rights reserved

Introduction
The ISO/IEC 20944 series of International Standards provides the bindings and their interoperability for
metadata registries, such as those specified in the ISO/IEC 11179 series of International Standards.
This part of ISO/IEC 20944 contains provisions that are common to coding bindings (Clauses 4-10) and the
coding bindings themselves (Clause 11 onward). The coding bindings have commonality in their
conceptualization of data instances and their internal structures. For example, common features include:
 using datatypes to characterize the nature and operations upon data;
 using ISO/IEC 11404 to define and declare datatypes;
 using common aggregate structures, such as array and record, to describe sets of data;
 using common navigation descriptions to reference components within a set of data.
The individual coding bindings each incorporate a mapping of common data semantics to their individual
binding requirements.
© ISO/IEC 2013 – All rights reserved v

INTERNATIONAL STANDARD ISO/IEC 20944-2:2013(E)

Information technology — Metadata Registries Interoperability
and Bindings (MDR-IB) —
Part 2:
Coding bindings
1 Scope
The ISO/IEC 20944 series of International Standards describes codings, application programming interfaces
(APIs), and protocols for interacting with an ISO/IEC 11179 metadata registry (MDR).
This part of ISO/IEC 20944 specifies provisions that are common across coding bindings for the
ISO/IEC 20944 series. This part of ISO/IEC 20944 includes the individual coding bindings themselves.
2 Normative references
The following referenced documents are indispensable for the application 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 11404:2007, Information technology — General-Purpose Datatypes (GPD)
ISO/IEC 20944-1:2013, Information technology — Metadata Registries Interoperability and Bindings
(MDR-IB) — Framework, common vocabulary, and common provisions for conformance
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 20944-1 apply.
4 Intended use of this part of ISO/IEC 20944
Bindings concern the mapping of one standard (or framework) into another standard (or framework).
Coding bindings concern the mapping of instances of data models to code elements (representations of data).
More than one standard (or framework) may be used to complete the mapping.
The ISO/IEC 20944 series of International Standards uses at least three tiers of mappings. The first tier
concerns the main kind of mapping for the binding: coding bindings, API bindings, and protocol bindings. The

For example, an ASN.1 binding of "technical specification XYZ" implies mapping the features and requirements of
"technical specification XYZ" to the features and capabilities of the ASN.1 standard.
When viewed as a series of layers (e.g., data model = Standard XYZ, coding binding = ASN.1, encoding = ASN.1
Basic Encoding Rules (BER)), bindings may also be viewed as "layered standards" or a "layering of standards".
© ISO/IEC 2013 – All rights reserved 1

second tier of mapping concerns the mapping of data model instances to a coding-independent representation
(CIR) of data — ISO/IEC 11404 specifies the syntax and semantics of this CIR. The third tier of mapping
concerns the mapping of CIR to a coding-specific representation (CSR) — Clauses 11 and onward describe
the coding-specific mappings. Additional tiers of mapping are possible, such as specifications of encoding
mappings.
The purpose of a common CIR of data is to support common semantics and interoperability among coding
bindings and other bindings, such as API and protocol bindings.
NOTE XML bindings are useful for integration with other XML technologies. The XML binding provides the
requirements of XML interchange without specifying the XML technologies (e.g., XML Schema) to implement the features.
DIVP bindings are useful for integration with name-value pair technologies, such as scripting systems, E-mail, and web
servers.
EXAMPLE A CIR is developed for a data model. Based upon this CIR, it is possible to transform one coding binding
(e.g., XML coding binding) to another coding binding (e.g., ASN.1 coding binding) while sharing common semantics (the
CIR) among the coding bindings. Likewise, one coding-specific representation (e.g., XML) can be transformed into another
coding-specific representation (e.g., ASN.1).
5 Abstr
...