ISO/TS 19115-3:2016

TECHNICAL ISO/TS
SPECIFICATION 19115-3
First edition
2016-08-15
Geographic information —
Metadata —
Part 3:
XML schema implementation for
fundamental concepts
Information géographique — Métadonnées —
Partie 3: Mise en oeuvre par des schémas XML
Reference number
©
ISO 2016
© ISO 2016, Published in Switzerland
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ii © ISO 2016 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Conformance . 1
2.1 General . 1
2.2 Conformance classes for metadata modules . 2
2.3 Conformance classes for metadata interchange documents . 3
3 Normative references . 3
4 Terms and definitions . 3
5 Symbols and abbreviated terms . 4
5.1 Acronyms . 4
5.2 Namespaces . 5
6 Requirements . 8
6.1 Automated generation of XML schema . 8
6.2 Multilingual adaptability and polymorphism . 8
6.3 Introduction to requirements classes . 8
6.4 Core Requirements . 9
6.5 Requirements for metadata modules . 9
6.6 Requirements for metadata interchange documents .18
6.7 Requirements dependency diagrams .24
7 Extensions to the UML models in the ISO geographic information series of
International Standards for this schema .25
8 Encoding approach and rules .26
8.1 UML packages and XML namespaces .26
8.2 UML model for XML implementation .26
8.3 Implementation approach for decoupling XML packages .26
8.3.1 General.26
8.3.2 Implementation approach to decouple optional classes.29
8.4 XML encoding rules.31
8.5 Default values .32
Annex A (normative) Abstract test suite .33
Annex B (informative) Geographic metadata XML resources.47
Annex C (informative) Encoding descriptions .49
Annex D (informative) Implementation examples .51
Bibliography .64
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
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 ISO documents 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 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).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on 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 the following URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 211, Geographic information/Geomatics.
A list of all parts in the ISO 19115 series can be found on the ISO website.
iv © ISO 2016 – All rights reserved

Introduction
ISO 19115-1 explains the importance of metadata, specifies a model for describing geographic
information resources by defining metadata entities, elements and terminology, and establishing
an extension procedure for additional metadata content. ISO 19115-1:2014, Annex G describes the
revisions from ISO 19115:2003. The revised content model also incorporates metadata elements
defined in ISO 19119:2005 and ISO 19119:2005/Amd 1:2008 for metadata describing web services.
More detailed metadata for geographic data types and data quality are defined in other ISO geographic
information standards (e.g. ISO 19110 and ISO 19157). Where necessary, interpretations of some other
ISO geographic information standards are incorporated for this implementation.
ISO 19115-2 extends ISO 19115-1 by adding models for acquisition information and extending the models
for metadata (MD_Metadata), data quality (DQ_DataQuality, now in ISO 19157), spatial representation
(MD_SpatialRepresentation), and content information (MD_ContentInformation).
ISO 19115-1 and ISO 19115-2 define conceptual models for metadata content that are independent of
any particular encoding scheme. ISO/TS 19139 and ISO/TS 19139-2 define eXtensible Markup Language
(XML) schemas for encoding that content. This document defines XML encodings for ISO 19115-1
and ISO 19115-2 metadata content. This integrated schema makes it possible to use concepts
from ISO 19115-1 and ISO 19115-2 together in metadata instance documents, effectively replacing
ISO/TS 19139 and ISO/TS 19139-2 and enables automated validation and interchange of ISO 19115-1
and ISO 19115-2, metadata content using standard software tools.
The integrated schema were derived from ISO 19115-1 and ISO 19115-2 conceptual models using the
rules defined in ISO 19118:2011, Annex A, ISO/TS 19139 applied to an adopted implementation-ready
UML version of the conceptual models as described in Clause 8. The implementation approach enables
modularization and eases reuse of elements of the conceptual models. Abstract classes were added
to the ISO geographic information harmonized model, without altering the semantics, to create an
implementation model that was used for this XML implementation (see Clause 8 for details).
The primary use case envisioned for this XML implementation is the exchange of geographic
metadata in a client-server environment exemplified by the World Wide Web, in which the internal
management and structure of metadata content is independent of the encoding used for exchange
of metadata information. Adoption of this geographic metadata XML schema within an information-
sharing community will garner the benefits of standardization for resource discovery, access, use, and
understanding.
TECHNICAL SPECIFICATION ISO/TS 19115-3:2016(E)
Geographic information — Metadata —
Part 3:
XML schema implementation for fundamental concepts
1 Scope
This document defines an integrated XML implementation of ISO 19115-1, ISO 19115-2, and concepts
from ISO/TS 19139 by defining the following artefacts:
a) a set of XML schema required to validate metadata instance documents conforming to conceptual
model elements defined in ISO 19115-1, ISO 19115-2, and ISO/TS 19139;
b) a set of ISO/IEC 19757-3 (Schematron) rules that implement validation constraints in the
ISO 19115-1 and ISO 19115-2 UML models that are not validated by the XML schema;
c) an Extensible Stylesheet Language Transformation (XSLT) for transforming ISO 19115-1 metadata
encoded using the ISO/TS 19139 XML schema and ISO 19115-2 metadata encoded using the
ISO/TS 19139-2 XML schema into an equivalent document that is valid against the XML schema
defined in this document.
This document describes the procedure used to generate XML schema from ISO geographic information
conceptual models related to metadata. The procedure includes creation of an UML model for XML
implementation derived from the conceptual UML model.
This implementation model does not alter the semantics of the target conceptual model, but adds
abstract classes that remove dependencies between model packages, tagged values and stereotypes
required by the UML to XML transformation software, and refactors the packaging of a few elements
into XML namespaces. The XML schema has been generated systematically from the UML model for
XML implementation according to the rules defined in ISO/TS 19139 or ISO 19118.
2 Conformance
2.1 General
In order to claim conformance to a conformance class defined in this document, an XML instance shall
validate against the test procedures specified in Annex A. These tests include validation using a specific
XML schema document, as well as Schematron rule documents that test conformance with constraints
specified by the base conceptual model that are not tested by XML schema validation. Each namespace
module and interchange document schema defined by the implementation carries with it an implicit
conformance class for xml instance documents. This conformance class tests the requirement that
xml element and attribute instances from the namespace shall be well formed and valid. The test is
validation with a specific XML schema and Schematron rule set if necessary. The framework, concepts,
and methodology for testing, and the criteria to be achieved to claim conformance are specified in
ISO 19105.
Implementers may choose to define other “information exchange” document schemas that import
normative XML schemas not specified here to identify and validate interchange documents. The design
of these schemas will be contingent on the requirements of the user community for the particular
information exchange. These information exchange schema should be documented in a technical note.
2.2 Conformance classes for metadata modules
This document defines a set of conformance classes for various content modules defined by
ISO 19115-1 and ISO 19115-2 to allow these to be used as components in other interchange document
implementations. Each module is packaged in a separate XML namespace. Table 1 lists the module
defined in this document.
Table 1 — Conformance classes defined for metadata modules
Conformance class name
a b
Namespace Conformance class URI
(implemented clause)
/mcc/1.0 /conf/common-classes-xml Valid XML instance of common classes namespace
(this document)
/cit/1.0 /conf/citation-xml Valid XML instance of citation namespace
(ISO 19115-1:2014, 6.6.2)
/lan/1.0 /conf/language-localisation-xml Valid XML instance of language localization
namespace (ISO 19115-1:2014, 6.7)
/mas/1.0 /conf/application-schema-xml Valid XML instance of application schema
namespace (ISO 19115-1:2014, 6.5.13)
/mac/1.0 /conf/ acquisition-xml Valid XML instance of metadata for acquisition
namespace (ISO 19115-2:2009, A.2.5)
/mco/1.0 /conf/constraints-xml Valid XML instance of constraints namespace
(ISO 19115-1:2014, 6.5.4)
/gex/1.0 /conf/geospatial-extent-xml Valid XML instance of geospatial extent namespace
(ISO 19115-1:2014, 6.6.1)
/mdb/1.0 /conf/metadata-base-xml Valid XML instance of metadata base namespace
(ISO 19115-1:2014, 6.5.2)
/mmi/1.0 /conf/maintenance-information-xml Valid XML instance of maintenance information
namespace (ISO 19115-1:2014, 6.5.6)
/mpc/1.0 /conf/portrayal-catalogue-xml Valid XML instance of portrayal catalogue
namespace (ISO 19115-1:2014, 6.5.10)
/mrc/1.0 /conf/resource-content-xml Valid XML instance of resource content namespace
(ISO 19115-1:2014, 6.5.9, ISO 19115-2)
/mrd/1.0 /conf/resource-distribution-xml Valid XML instance of resource distribution
namespace (ISO 19115-1:2014, 6.5.11)
/mri/1.0 /conf/resource-identification-xml Valid XML instance of resource identification
namespace (ISO 19115-1:2014, 6.5.6)
/mrl/1.0 /conf/lineage-xml Valid XML instance of resource lineage namespace
(ISO 19115-1:2014, 6.5.5, ISO 19115-2)
/mrs/1.0 /conf/reference-system-xml Valid XML instance of reference system namespace
(ISO 19115-1:2014, 6.5.8)
/msr/1.0 /conf/spatial-representation-xml Valid XML instance of spatial representation
(ISO 19115-1:2014, 6.5.7, ISO 19115-2)
/msr/1.0 /conf/spatial-representation-xml Valid XML instance of spatial representation
(ISO 19115-1:2014, 6.5.7, ISO 19115-2)
/srv/2.0 /conf/service-metadata-xml Valid XML instance of service metadata
namespace (ISO 19115-1:2014, 6.5.14)
/mex/1.0 /conf/metadata-extension-xml Valid XML instance of metadata extension
namespace (ISO 19115-1:2014, 6.5.12)
/gcx/1.0 /conf/extended-types-xml XML implementation of geospatial common
extended types (ISO/TS 19139:2007, 7.2)
a
For complete namespace URIs, prefix “http://standards.iso.org/iso/19115/-3”.
b
All Conformance Class URIs are HTTP URIs, prefix “http://standards.iso.org/iso/19115/-3” to the paths in the table
cell to get the complete URI.
2 © ISO 2016 – All rights reserved

2.3 Conformance classes for metadata interchange documents
This document defines a set of XML schema that import various modular namespace components to
define useful metadata interchange documents. Each of these document schema has an associated
requirements and conformance class, and a namespace URI to identify the document type. Table 2 lists
these interchange document schemes.
Table 2 — Conformance classes for metadata interchange
a b
Namespace Conformance class URI Conformance class name
mdb/1.0 /conf/metadata-minimal-instance Minimum XML metadata instance document
mds/1.0 /conf/metadata-data-or-service- Complete valid XML metadata instance document
instance
md1/1.0 /conf/metadata-extended-types- Valid XML metadata instance document with
instance extended types
/md2/1.0 /conf/extended-metadata-instance Valid XML metadata instance document with
extended content model
/cat/1.0 /conf/catalogue-instance Valid XML catalogue instance document
/mda/1.0 /conf/metadata-application-instance Valid XML instance of metadata application
namespace
/mdt/1.0 /conf/metadata-data-transfer- Valid XML instance of metadata for data transfer
instance namespace
a
For complete namespace URIs, prefix “http://standards.iso.org/iso/19115/-3’”.
b
All conformance class URIs are HTTP URIs, prefix “http://standards.iso.org/iso/19115/-3” to the paths in the table cell
to get the complete URI.
3 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 19110, Geographic information — Methodology for feature cataloguing
ISO 19115-1:2014, Geographic information — Metadata — Part 1: Fundamentals
ISO 19115-2:2009, Geographic information — Metadata — Part 2: Extensions for imagery and gridded data
ISO 19136, Geographic information — Geography Markup Language (GML)
ISO 19157, Geographic information — Data quality
ISO/TS 19139:2007, Geographic information — Metadata — XML schema implementation
4 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
4.1
namespace
collection of names, identified by a URI reference, which are used in XML documents as element
names and attribute names
Note 1 to entry: The combination of a namespace URI and element or attribute name are intended to be a globally
unique identifier for that model element
[SOURCE: W3C XML Namespaces:1999]
4.2
package
general purpose mechanism for organizing elements into groups
EXAMPLE Identification information package, metadata entity set information package, constraint
information package.
Note 1 to entry: Packages may be nested within other packages. Both model elements and diagrams may appear
in a package.
Note 2 to entry: A package provides a namespace (4.1) for the grouped elements.
[SOURCE: ISO 19103:2015, 4.27, modified — Examples and notes to entry have been added.]
4.3
realization
semantic relationship between classifiers, wherein one classifier specifies a contract that another
classifier guarantees to carry out
[SOURCE: ISO/TS 19139:2007, 4.3]
4.4
polymorphism
characteristic of being able to assign a different meaning or usage to something in different contexts
– specifically, to allow an entity such as a variable, a function, or an object to have more than one form
Note 1 to entry: Realization (4.3) indicates inheritance of behaviour without inheritance of structure.
[SOURCE: ISO/TS 19139:2007, 4.4, modified — Note 1 to entry has been added.]
5 Symbols and abbreviated terms
5.1 Acronyms
GML Geography Markup Language
HTML HyperText Markup Language
UML Unified Modeling Language
URI Universal Resource Identifier
XML Extensible Markup Language
XPath XML Path Language
XSD XML Schema Definition
XSL Extensible Style Language
XSLT Extensible Stylesheet Language Transformation
4 © ISO 2016 – All rights reserved

5.2 Namespaces
XML namespaces defined in this document are identified by URIs that follow the pattern: http://
standards.iso.org/iso/19115/-3/xxx/N.M, where xxx is a three-alphanumeric-character namespace
abbreviation, N is the major version number, and M is the minor version number. Dereferencing the
namespace URI as a resource locator will retrieve a description of the namespace, links to description
of the content of the namespace, and links to the base specification the namespace implements and to
the normative XML schema location.
Because the full URI is cumbersome for reading, writing, and in human discussion, this document
will refer to the namespaces using abbreviations. Table 3 lists namespaces from other specifications
imported by this implementation, and the short string in the left column of Table 3 is the associated
abbreviation used to reference the namespace and to associate an XML element with the namespace
URI in a fully qualified name. The second column contains an English-language description of the
namespace, and the string in the right column is the URI that identifies the namespace. Tables 4 and 5 list
abbreviations and other information for namespaces used for UML packages defined in ISO 19115-1 and
for namespaces defined in this document that import multiple XML namespaces to define interchange
document types.
Table 3 — External namespace URIs and namespace abbreviation conventions used in this
document
Namespace
abbreviation Name Namespace URI
convention
dqc Data quality common http://standards.iso.org/iso/19157/-2/dqc/1.0
fcc Feature catalogue common http://standards.iso.org/19110/fcc/1.0
gml Geography markup language http://www.opengis.net/gml/3.2
xlink XML linking language http://www.w3.org/1999/xlink
xs W3C XML schema definition http://www.w3.org/2001/XMLSchema
schema
Table 4 — Namespace URIs and namespace abbreviation conventions defined and used in this
document for packages defined in ISO 19115-1
Namespace
Namespace
a
abbreviation Scope Namespace URI UML package
name
convention
Cat CATalogue elements for codelist http://standards.iso.org/ Catalogues
catalogues, and example iso/19115/-3/cat/1.0 (ISO/TS 19139)
catalogues from
ISO/TS 19139 updated
for compatibility with
new schema
cit CITation Utility elements for http://standards.iso.org/ Citation and
citation, identification, iso/19115/-3/cit/1.0 responsible
and web linkage of party information
resources
gco Metadata core Basic data types http://standards.iso.org/ From
iso/19115/-3/gco/1.0 ISO/TS 19139
gcx Geospatial Elements for xml http://standards.iso.org/ Web
Common implementation, from iso/19115/-3/gcx/1.0 environment
eXtension ISO/TS 19139 updated (ISO/TS 19139)
for compatibility with
new schema
a
UML packages are defined in ISO 19115-1 unless noted otherwise.
Table 4 (continued)
Namespace
Namespace
a
abbreviation Scope Namespace URI UML package
name
convention
gex Geospatial Elements for specifying http://standards.iso.org/ Extent
EXtent geospatial properties of iso/19115/-3/gex/1.0 information
a resource, including
extent and spatial
reference systems
gmw GML wrapper Namespace that http://standards.iso.org/ From
implements properties iso/19115/-3/gmw/1.0 ISO/TS 19139
with values specified by
GML classes
lan LANguage Elements for cultural http://standards.iso.org/ Language-
localization and linguistic adaptability iso/19115/-3/lan/1.0 characterset
localization
information
mas Metadata for Application schema used http://standards.iso.org/ Application
application to build a dataset iso/19115/-3/mas/1.0 schema
schema information
mcc Metadata for Elements used by all http://standards.iso.org/ Common classes
common classes other packages iso/19115/-3/mcc/1.0
mco Metadata for Specify constraints on http://standards.iso.org/ Constraint
constraints access and use iso/19115/-3/mco/1.0 information
mdb Metadata base Define metadata root http://standards.iso.org/ Metadata
element and properties, iso/19115/-3/mdb/1.0 information
with abstract
implementation. This
namespace is intended
to support profile
development.
mex Metadata for Extensions to metadata http://standards.iso.org/ Metadata
extension content iso/19115/-3/mex/1.0 extension
information
mmi Metadata for Maintenance of http://standards.iso.org/ Maintenance
maintenance resources and metadata iso/19115/-3/mmi/1.0 information
information
mpc Metadata for Portrayal of described http://standards.iso.org/ Portrayal
portrayal resource iso/19115/-3/mpc/1.0 catalogue
catalogue information
mrc Metadata for Resource data structure http://standards.iso.org/ Content
resource and content iso/19115/-3/mrc/1.0 information
content
mrd Metadata for How a resource is http://standards.iso.org/ Distribution
resource accessed iso/19115/-3/mrd/1.0 information
distribution
mri Metadata for Identifying resources http://standards.iso.org/ Identification
resource iso/19115/-3/mri/1.0 information
identification
mrl Metadata for Resource provenance http://standards.iso.org/ Lineage
resource iso/19115/-3/mrl/1.0 information
lineage
a
UML packages are defined in ISO 19115-1 unless noted otherwise.
6 © ISO 2016 – All rights reserved

Table 4 (continued)
Namespace
Namespace
a
abbreviation Scope Namespace URI UML package
name
convention
mrs Metadata for Spatial reference system http://standards.iso.org/ Reference
reference for resource content iso/19115/-3/mrs/1.0 system
system information
msr Metadata for Encoding of location http://standards.iso.org/ Spatial
spatial information in resource iso/19115/-3/msr/1.0 representation
representation content information
srv SeRVice Information specific to http://standards.iso.org/ Service
metadata service resources, iso/19115/-3/srv/2.0 metadata
inherited from ISO 19119 information
into ISO 19115-1
a
UML packages are defined in ISO 19115-1 unless noted otherwise.
Table 5 — Namespace URIs and namespace abbreviation conventions to identify metadata
interchange document types that aggregate multiple namespaces
Namespace
Namespace
a
abbreviation Scope Namespace URI UML package
name
convention
mdb Metadata base Implement elements and http://standards.iso.org/
properties for minimal iso/19115/-3/mdb/1.0
metadata properties
required by ISO 19115-1.
mds Metadata for Implement all the http://standards.iso.org/ Metadata
data and optional metadata iso/19115/-3/mds/1.0 information
services properties associated
with the base
MD_Metadata and
MI_Metadata (from
ISO 19115-2) element.
This namespace is
intended to support
catalogue services.
md1 Metadata for Implement all the http://standards.iso.org/
data and optional metadata iso/19115/-3/md1/1.0
services with properties associated
geospatial with the base
common MD_Metadata element
extensions and geospatial common
extensions.
mda Metadata Includes classes for http://standards.iso.org/ Metadata
application describing resource iso/19115/-3/mda/1.0 application
collections with information
hierarchical metadata.
mdt Metadata for Includes classes for http://standards.iso.org/ Metadata-based
data transfer describing packages of iso/19115/-3/mdt/1.0 data transfers
data for transfer. (ISO/TS 19139)
md2 Metadata with Extends metadata by http://standards.iso.org/ Metadata
extensions including classes that iso/19115/-3/md2/1.0 extension
allow metadata information
extensions to be
described.
NOTE Namespaces are arranged from simplest to most complex.
a
Blank cells indicate that no equivalent package is defined in ISO 19115-1 or ISO/TS 19139.
6 Requirements
6.1 Automated generation of XML schema
A major design objective for ISO geographic information standards information models is to enable
production of XML schema following standard rules and implementation patterns such that machine
processing of UML models can generate the XML schema. The intention is to promote predictability,
extensibility, reuse of schema, and interoperability with other ISO geographic information standards
implementations. The resulting XML schemas are algorithmically derived from the normative UML
models for ISO geographic information standards, which promotes consistency in the resulting schema.
The resulting schemas are predictable since UML classes, attributes, associations, etc. are encoded
following consistent rules and patterns.
Another requirement of this implementation is to modularize the encoding of ISO 19115-1 content
by defining XML elements in several namespaces, with a minimum of dependencies between them
(see 6.4). The purpose of grouping XML elements into namespaces is to define loosely coupled units
of information representation capability that facilitate reuse in other applications. The contents of
several XML namespaces are defined in this document, which may be reused by importing into other
XML schema. Use of an existing XML schema is advantageous because it reduces the amount of new
schema development required, and because existing software may be available that can process model
elements conforming to an existing XML schema.
The ISO 19115-1 metadata conceptual schema is designed to support transfer of resource documentation
(metadata) among and within user communities. A third objective of the implementation for this
document is to define standard document types that include elements from multiple namespace
modules, designed for specific information exchange scenarios. Six “aggregation” namespaces are
defined that import multiple modules to meet various requirements (see 6.5).
6.2 Multilingual adaptability and polymorphism
Cultural and linguistic adaptability is a requirement for metadata elements with text content. In
ISO 19115-1:2014, Annex F, there is an informative discussion of multilingual textual metadata elements.
In order to enable the interoperability of multilingual instance documents, the XML implementation
for this document follows the implementation specified in ISO/TS 19139. The property type encodings
described in ISO/TS 19139:2007, 8.4, enable extensions to the XML schema that implement property
values using element types not included in the base XML schema. Such polymorphism (see definition
in 4.4) allows user communities to modify geographic metadata to meet their organizational needs.
This pattern is used to provide cultural and linguistic adaptability support through metadata instance
documents containing content in one or more languages that do not violate cardinality rules defined in
ISO 19115-1. The lan namespace defines a CharacterString property type that includes a CharacterString
value, and zero to many PT_FreeText elements, each of which is a language-localized character string
that may be included inline or by reference. Using this extension, a single metadata document may
include content strings in a variety of languages, but clients that are not programmed for multilingual
content will still work because the standard CharacterString element is present.
Another example of polymorphism is the name attribute of type CharacterString in the CI_Individual
class in ISO 19115-1; if a more structured representation is required (e.g. first, middle, and last name
elements), polymorphism allows extension of the name element implementation in a user-defined
namespace that may be substituted for CharacterString within a metadata instance. These extensions
will be understandable to users who recognize the extension namespace, but in general such extensions
will not interoperate with client software not designed to work with them.
6.3 Introduction to requirements classes
The requirements to create valid XML metadata instances for the conceptual model presented in
ISO 19115-1 are defined in 6.4 through 6.7. In Tables 6 through 10, HTTP URIs are used to identify clauses
in corresponding normative ISO standards that do not define and assign identifiers to requirements
and conformance classes that can be referenced in this document. These are constructed using http://
8 © ISO 2016 – All rights reserved

standards.iso.org/iso as the base, with the source project ID, edition number, and “spec#N.N.N” as
the final token where the “N.N.N” part identifies the source clause in the standards document. Each
implemented package sets requirements for validating XML instances that use elements in the package.
The requirements are grouped into core requirements that apply to all instance validation, requirements
for metadata modules that define the various components of metadata content, and requirements for
actual metadata interchange documents that are assembled by importing collections of modules. The
metadata modules are designed to minimize dependencies between modules to facilitate their reuse in
other application schema.
6.4 Core Requirements
The requirements class specified in Table 6 defines requirements that shall be met by any XML instance
document based on this document.
Table 6 — Requirements for metadata core
Requirements class
http://standards.iso.org/iso/19115/-3/req/metadata-core
Target type XML instance document
Name Core requirements for metadata properties
Dependency http://standards.iso.org/iso/19139/spec#8.4.1
Requirement /req/metadata-core/property-type-content
A property element instance SHALL have exactly one of inline content (by-value) that is
a schema-valid XML Class instance, a xlink:href attribute (by-reference value), or a
gco:nilReason attribute (nil value).
Requirement /req/metadata-core/instance-validation
XML instance documents SHALL be well formed and valid. A conformance class is defined
on this requirement for each namespace that specifies the normative XML schema and
Schematron rule (if applicable) files that are used to test conformance.
Requirement /req/metadata-core/base-data-types
Base data types SHALL be implemented according to rules set forth in ISO/TS 19139.
6.5 Requirements for metadata modules
A collection of modular XML namespaces are used to implement the various content packages defined
in ISO 19115-1 and ISO 19115-2. The modules are summarized in Table 7, and the requirements for
XML instances of each module are defined and assigned identifiers in Table 8. These identifiers are
referenced in the definition of conformance classes and tests in Annex A.
Table 7 — Summary of metadata modules defined by this document
Namespace Name Clauses implemented
http://standards.iso.org/ Catalogue http://standards.iso.org/iso/19139/
iso/19115/-3/cat/1.0 spec#7.4.4
http://standards.iso.org/ Citation and responsible party http://standards.iso.org/iso/19115/-
a
iso/19115/-3/cit/1.0 information 1/spec#6.6.3
http://standards.iso.org/ Metadata core http://standards.iso.org/iso/19139/
iso/19115/-3/gco/1.0 spec#9.7
http://standards.iso.org/ Geospatial common extended types http://standards.iso.org/iso/19139/
iso/19115/-3/gcx/1.0 spec#7.2
a
There is a circular dependency between the citation and common classes packages, but because of the policy that
the implementation package should match the base abstract schema (ISO 19115-1) packaging, these are implemented as
separate namespaces.
Table 7 (continued)
Namespace Name Clauses implemented
http://standards.iso.org/ Metadata for geospatial extent http://standards.iso.org/iso/19115/-
iso/19115/-3/gex/1.0 1/spec#6.6.1
http://standards.iso.org/ GML wrapper http://standards.iso.org/iso/19139/
iso/19115/-3/gmw/1.0 spec#9.4;
http://standards.iso.org/iso/19139/
spec#9.5;
http://standards.iso.org/iso/19139/
spec#9.6
http://standards.iso.org/ Language localization http://standards.iso.org/iso/19139/
iso/19115/-3/lan/1.0 spec#7.3;
http://standards.iso.org/iso/19115/-
1/spec#6.7.2
http://standards.iso.org/ Metadata for acquisition http://standards.iso.org/iso/19115/-
iso/19115/-3/mac/1.0 2/spec#A.2.5
http://standards.iso.org/ Metadata for application schema http://standards.iso.org/iso/19115/-
iso/19115/-3/mas/1.0 1/spec#6.5.13
http://standards.iso.org/ Metadata common classes http://standards.iso.org/iso/19115/-
iso/19115/-3/mcc/1.0 1/spec#6.6.4, including abstract
classes necessary for encoding
optional class property types defined
in ISO 19115-1 according to the
implementation approach described
a
in Clause 8
http://standards.iso.org/ Metadata for constraints http://standards.iso.org/iso/19115/-
iso/19115/-3/mco/1.0 1/spec#6.5.4
http://standards.iso.org/ Metadata base http://standards.iso.org/iso/19115/-
iso/19115/-3/mdb/1.0 1/spec#6.5.2
http://standards.iso.org/ Metadata for metadata extension http://standards.iso.org/iso/19115/-
iso/19115/-3/mex/1.0 1/spec#6.5.12
http://standards.iso.org/ Metadata for maintenance information http://standards.iso.org/iso/19115/-
iso/19115/-3/mmi/1.0 1/spec#6.5.6
http://standards.iso.org/ Metadata for portrayal catalogue http://standards.iso.org/iso/19115/-
iso/19115/-3/mpc/1.0 1/spec#6.5.10
ht t p://s t a nd a r d s .i so. or g / Metadata for resource content http://standards.iso.org/iso/19115/-1/
iso/19115/-3/mrc/1.0 spec#6.5.9
ht t p://s t a nd a r d s .i so. or g / Metadata for resource distribution http://standards.iso.org/iso/19115/-1/
iso/19115/-3/mrd/1.0 spec#6.5.11
ht t p://s t a nd a r d s .i so. or g / Metadata for resource identification http://standards.iso.org/iso/19115/-1/
iso/19115/-3/mri/1.0 spec#6.5.3
ht t p://s t a nd a r d s .i so. or g / Metadata for resource lineage http://standards.iso.org/iso/19115/-1/
iso/19115/-3/mrl/1.0 spec#6.5.5
ht t p://s t a nd a r d s .i so. or g / Metadata for reference system http://standards.iso.org/iso/19115/-1/
iso/19115/-3/mrs/1.0 spec#6.5.8
ht t p://s t a nd a r d s .i so. or g / Metadata for spatial representation http://standards.iso.org/iso/19115/-1/
iso/19115/-3/msr/1.0 spec#6.5.7
ht t p://s t a nd a r d s .i so. or g / Metadata for services http://standards.iso.org/iso/19115/-1/
iso/19115/-3/srv/2.0 spec#6.5.14
a
There is a circular dependency between the citation and common classes packages, but because of the policy that
the implementation package should match the base abstract schema (ISO 19115-1) packaging, these are implemented as
separate namespaces.
10 © ISO 2016 – All rights reserved

Table 8 — Requirements classes for XML instance documents for each namespace module
Requirement class
a b b
Namespace Dependencies Requirements
b
URI
c
/cat/1.0 /req/catalogue- /req/metadata-core, /req/catalogue-instance/validation
instance /req/language-
localisation-instance
c
/cit/1.0 /req/citation-instance /req/metadata-core /req/citation-instance/validation
/req/citation/individual-name
/req/common-classes-
Any instance of CI_Individual SHALL have
instance
either a “name” property value or a
“positionName” property value.
/req/citation/organisation-name
Any instance of CI_Organisation SHALL
have either a “name” property value or a
“logo” property value.
c
/gcx/1.0 /req/extended- /req/metadata-core /req/extended-types-instance/validation
types-instance /req/common-classes-
instance
/gex/1.0 /req/geospatial- /req/metadata-core /req/geospatial-extent-instance/valida-
c
extent-instance /req/common-classes- tion
instance /req/gml-wrap-
/req/geospatial-extent-instance/
per
value-required
If an EX_Extent element is instantiated,
then a value for either “description”,
“geographic-Element”, “temporalElement”
or “verticalElement” SHALL be present.
/req/geospatial-extent-instance/
vertical-crs
If an EX_VerticalExtent element is
instantiated, then a value for either
verticalCRSid or verticalCRS SHALL be
present.
/gmw/1.0 /req/gml-wrapper /req/metadata-core /req/gml-wrapper/implementation
http://standards.iso.
Property types implemented by GML
org/iso/19139/spec#9.4;
(ISO 19136) SHALL be implemented
http://standards.iso.
as property types as specified in
org/iso/19139/spec#9.5;
ISO/TS 19139:2007.
http://standards.iso.org/
/req/gml-wrapper/validation
iso/19139/spec#9.6
a
For complete namespace URIs, prefix “http://standards.iso.org/iso/19115/-3”.
b
All URIs are HTTP URIs, prefix “http://standards.iso.org/iso/19115/-3” to the paths in the table cell to get the
complete URI.
c
Validation requirements are all the same. Each module has a validation requirement that reflects the validation
requirement of the core requirements, and is associated with a conformance class that defines the XML schema and
Schematron rule set used to test validation.
Table 8 (continued)
Requirement class
a b b
Namespace Dependencies Requirements
b
URI
/lan/1.0 /req/language- http://standards.iso.org/ /req/language-localisation-
c
localisation-instance iso/19139/spec#7.3 instance/validati
...