Changes for page SDMX 3.1 Standards. Section 1. Framework

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@@ -77,14 +77,14 @@
  * **Consistency between the [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] and the [[SDMX Information Model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]]: **Certain aspects of the XML schemas and UML model have been more closely aligned, to allow for easier comprehension of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] model.
  * **Technical Bugs:** Some minor technical bugs have been identified in the registry interfaces and elsewhere. These bugs have been addressed.
  * **Support for Non-Time-[[Series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] Data in the Generic Format: **One area which has been extended is the ability to express non-time-[[series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] data as part of the generic data message.
--* **Simplification of the [[data structure definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] - specific message types: **Both [[time series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] ((% style="color:#e74c3c" %)version(%%) 2.0 Compact) and non-[[time series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] ((% style="color:#e74c3c" %)version(%%) 2.0 Cross Sectional) use the same underlying structure for a structure-specific formatted message, which is specific to the [[Data Structure Definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] of the [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].
++* **Simplification of the [[data structure definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] - specific message types: **Both [[time series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] (version 2.0 Compact) and non-[[time series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] (version 2.0 Cross Sectional) use the same underlying structure for a structure-specific formatted message, which is specific to the [[Data Structure Definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] of the [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].
  * **Simplification and better support for the metadata structure: **New use cases have been reported and these are now supported by a re-modelled [[metadata structure definition>>doc:sdmx:Glossary 2\.1.Metadata structure definition.WebHome]].
--* **Support for partial [[item schemes>>doc:sdmx:Glossary 2\.1.Item scheme.WebHome]] such as a [[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] list: **The (% style="color:#e74c3c" %)concept(%%) of a partial (subset) [[item scheme>>doc:sdmx:Glossary 2\.1.Item scheme.WebHome]] such as a partial [[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] list for use in exchange scenarios has been introduced**.**
++* **Support for partial [[item schemes>>doc:sdmx:Glossary 2\.1.Item scheme.WebHome]] such as a [[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] list: **The concept of a partial (subset) [[item scheme>>doc:sdmx:Glossary 2\.1.Item scheme.WebHome]] such as a partial [[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] list for use in exchange scenarios has been introduced**.**
  == 2.3 Major Changes from 2.1 to 3.0 ==
--[[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)version(%%) 3.0 introduces new features, improvements and changes to the Standard in the following key areas:
++[[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] version 3.0 introduces new features, improvements and changes to the Standard in the following key areas:
  (% class="wikigeneratedid" id="HInformationModel" %)
  **Information Model**
@@ -95,10 +95,10 @@
  * Support for [[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] list extension and discriminated union of [[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] lists
  * Improvements to structure mapping
  * Improvements to [[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] [[hierarchies>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] for data discovery
--* Improvements to (% style="color:#e74c3c" %)constraints
++* Improvements to [[constraints>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]]
  (% class="wikigeneratedid" id="HVersioningofStructuralMetadataArtefacts" %)
--**Versioning of [[Structural Metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]] [[Artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]**
++**Versioning of Structural Metadata Artefacts**
  Adoption of the three-number semantic versioning standard for [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]] [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] ([[__https:~~/~~/semver.org__>>https://https:semver.org]])
@@ -113,24 +113,24 @@
  (% class="wikigeneratedid" id="HSOAPWebServicesAPI" %)
  **SOAP Web Services API**
--* The SOAP web services API has been deprecated with (% style="color:#e74c3c" %)version(%%) 3.0 standardising on REST
++* The SOAP web services API has been deprecated with version 3.0 standardising on REST
  (% class="wikigeneratedid" id="HXML2CJSON2CCSVandEDITransmissionformats" %)
  **XML, JSON, CSV and EDI Transmission formats**
--The [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]], [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]] and [[SDMX-CSV>>doc:sdmx:Glossary 2\.1.SDMX-CSV.WebHome]] specifications have been extended and modified where needed to support the new features and changes such as [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] and microdata Obsolete [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] data message variants including Generic, Compact, Utility and Cross-sectional have been deprecated standardising on Structure Specific Data as the sole XML format for [[data exchange>>doc:sdmx:Glossary 2\.1.Data exchange.WebHome]] The [[SDMX-EDI>>doc:sdmx:Glossary 2\.1.SDMX-EDI.WebHome]] transmission format for structures and data has been deprecated The organisation of structures into ‘collections’ in [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] and [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]] structure messages has been flattened and simplified The option to reference structures in [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] and [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]] messages using Agency, ID and (% style="color:#e74c3c" %)Version(%%) has been deprecated with URN now exclusively used for all non-local referencing purpose
++The [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]], [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]] and [[SDMX-CSV>>doc:sdmx:Glossary 2\.1.SDMX-CSV.WebHome]] specifications have been extended and modified where needed to support the new features and changes such as [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] and microdata Obsolete [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] data message variants including Generic, Compact, Utility and Cross-sectional have been deprecated standardising on Structure Specific Data as the sole XML format for [[data exchange>>doc:sdmx:Glossary 2\.1.Data exchange.WebHome]] The [[SDMX-EDI>>doc:sdmx:Glossary 2\.1.SDMX-EDI.WebHome]] transmission format for structures and data has been deprecated The organisation of structures into ‘collections’ in [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] and [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]] structure messages has been flattened and simplified The option to reference structures in [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] and [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]] messages using Agency, ID and Version has been deprecated with URN now exclusively used for all non-local referencing purpose
--Several of the changes are ‘breaking’ meaning that, in specific cases, the (% style="color:#e74c3c" %)version(%%) 3.0 specification is not backwardly compatible with earlier (% style="color:#e74c3c" %)versions(%%) of the Standard.
++Several of the changes are ‘breaking’ meaning that, in specific cases, the version 3.0 specification is not backwardly compatible with earlier versions of the Standard.
  The principle breaking changes are:
  * REST API – The REST API is not backwardly compatible due to modifications to the URLs and query parameters resulting in breaking changes in four of the five main resources.
--* SOAP API – Deprecation of the SOAP API means that existing systems designed to use SOAP will not work with (% style="color:#e74c3c" %)version(%%) 3.0 registries.
--* [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] – [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 2.1 and earlier structure, data and metadata XML messages are not valid in (% style="color:#e74c3c" %)version(%%) 3.0. Specifically: legacy data messages including Generic, Compact and Utility are no longer supported. The remaining Structure Specific data message has been changed to support new features such as reporting of [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] as part of the [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]], Structure messages have a number of breaking changes, principally modification to the information model, removal of the agency-(% style="color:#e74c3c" %)version(%%)-id option for referencing [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] and changes to the way the structures are organised into ‘collections’ within the message.
--* [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]] – [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 2.1 structure, data and metadata JSON messages are not valid in (% style="color:#e74c3c" %)version(%%) 3.0. The data message has been changed to support the improved REST data queries, in particular the ability to retrieve in one operation data from multiple [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] with potentially different [[Data Structure Definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]]. Breaking changes similar to those for the [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] transmission format have been made to the structure message.
--* [[SDMX-CSV>>doc:sdmx:Glossary 2\.1.SDMX-CSV.WebHome]] - The CSV data and [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] messages are not backwardly compatible with those under (% style="color:#e74c3c" %)version(%%) 2.1 due to changes to the structure of the messages needed to support new features such as the improved REST API data queries.
--* [[SDMX-EDI>>doc:sdmx:Glossary 2\.1.SDMX-EDI.WebHome]] – Deprecation of the EDI transmission format means that existing systems designed to send or receive structures or data in EDI will not work with (% style="color:#e74c3c" %)version(%%) 3.0 registries.
--* Information Model – Several structures have been changed in the (% style="color:#e74c3c" %)version(%%) 3.0 model and three removed. For these reasons the (% style="color:#e74c3c" %)version(%%) 3.0 model is not directly compatible with (% style="color:#e74c3c" %)version(%%) 2.1 or earlier, although conversion of specific [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] is possible under some circumstances. Loss of information during the conversion process however means that in cases like structure mapping, the conversion is not reversible i.e. it is not possible to recreate the 2.1 structure once it has been converted to the 3.0 model.
++* SOAP API – Deprecation of the SOAP API means that existing systems designed to use SOAP will not work with version 3.0 registries.
++* [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] – [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 2.1 and earlier structure, data and metadata XML messages are not valid in version 3.0. Specifically: legacy data messages including Generic, Compact and Utility are no longer supported. The remaining Structure Specific data message has been changed to support new features such as reporting of [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] as part of the [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]], Structure messages have a number of breaking changes, principally modification to the information model, removal of the agency-version-id option for referencing [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] and changes to the way the structures are organised into ‘collections’ within the message.
++* [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]] – [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 2.1 structure, data and metadata JSON messages are not valid in version 3.0. The data message has been changed to support the improved REST data queries, in particular the ability to retrieve in one operation data from multiple [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] with potentially different [[Data Structure Definitions>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]]. Breaking changes similar to those for the [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] transmission format have been made to the structure message.
++* [[SDMX-CSV>>doc:sdmx:Glossary 2\.1.SDMX-CSV.WebHome]] - The CSV data and [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] messages are not backwardly compatible with those under version 2.1 due to changes to the structure of the messages needed to support new features such as the improved REST API data queries.
++* [[SDMX-EDI>>doc:sdmx:Glossary 2\.1.SDMX-EDI.WebHome]] – Deprecation of the EDI transmission format means that existing systems designed to send or receive structures or data in EDI will not work with version 3.0 registries.
++* Information Model – Several structures have been changed in the version 3.0 model and three removed. For these reasons the version 3.0 model is not directly compatible with version 2.1 or earlier, although conversion of specific [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] is possible under some circumstances. Loss of information during the conversion process however means that in cases like structure mapping, the conversion is not reversible i.e. it is not possible to recreate the 2.1 structure once it has been converted to the 3.0 model.
  The [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 Major Changes document provides more information including an analysis of the breaking changes.
@@ -139,14 +139,14 @@
  (% class="wikigeneratedid" id="HInformationModel-1" %)
  **Information Model**
--* Addition of [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] (% style="color:#e74c3c" %)Constraint(%%) property to a [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]
++* Addition of [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] Constraint property to a [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]
  * Addition of evolving structure property to a [[Data Structure Definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]]
--* Remove (% style="color:#e74c3c" %)version(%%) property on [[Categorisation>>doc:sdmx:Glossary 2\.1.Categorisation.WebHome]]
--* Simplification of (% style="color:#e74c3c" %)Constraints
++* Remove version property on [[Categorisation>>doc:sdmx:Glossary 2\.1.Categorisation.WebHome]]
++* Simplification of [[Constraints>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]]
  ** Removal of Advanced [[Release Calendar>>doc:sdmx:Glossary 2\.1.Release policy - release calendar.WebHome]]
--** Removal of Role, Data (% style="color:#e74c3c" %)Constraints(%%) only restrict data that can be reported
--** Restrict (% style="color:#e74c3c" %)constraint(%%) targets to Identifiable structures (not URLs)
--** Addition of Availability (% style="color:#e74c3c" %)Constraint(%%) to define actual data
++** Removal of Role, Data [[Constraints>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]] only restrict data that can be reported
++** Restrict [[constraint>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]] targets to Identifiable structures (not URLs)
++** Addition of Availability [[Constraint>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]] to define actual data
  (% class="wikigeneratedid" id="HDocumentation" %)
  **Documentation**
@@ -159,7 +159,6 @@
  == 3.1 Process Patterns ==
--
  [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] identifies three basic process patterns regarding the exchange of statistical data and metadata. These can be described as follows:
 . //**[[Bilateral exchange>>doc:sdmx:Glossary 2\.1.Bilateral exchange.WebHome]]**~:// All aspects of the exchange process are agreed between counterparties, including the mechanism for exchange of data and metadata, the formats, the frequency or schedule, and the mode used for communications regarding the exchange. This is perhaps the most common process pattern.
@@ -179,11 +179,11 @@
  == 3.3 Statistical Data and Metadata ==
--To avoid confusion about which "data" and "metadata" are the intended content of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] formats specified here, a statement of scope is offered. Statistical "data" are sets of often numeric observations which typically have time associated with them. They are associated with a set of metadata values, representing specific (% style="color:#e74c3c" %)concepts(%%), which act as identifiers and descriptors of the data. These metadata values and (% style="color:#e74c3c" %)concepts(%%) can be understood as the named [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] of a multi-dimensional co-ordinate system, describing what is often called a "cube" of data.
++To avoid confusion about which "data" and "metadata" are the intended content of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] formats specified here, a statement of scope is offered. Statistical "data" are sets of often numeric observations which typically have time associated with them. They are associated with a set of metadata values, representing specific concepts, which act as identifiers and descriptors of the data. These metadata values and concepts can be understood as the named [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] of a multi-dimensional co-ordinate system, describing what is often called a "cube" of data.
  [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] identifies a standard technique for modelling, expressing, and understanding the structure of this multi-dimensional "cube", allowing automated processing of data from a variety of sources. This approach is widely applicable across types of data and attempts to provide the simplest and most easily comprehensible technique that will support the exchange of this broad set of data and related metadata.
--The term "metadata" is very broad indeed. A distinction can be made between “structural” metadata – those (% style="color:#e74c3c" %)concepts(%%) used in the description and identification of statistical data and metadata – and “reference” metadata – the larger set of (% style="color:#e74c3c" %)concepts(%%) that describe and qualify statistical [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] and processing more generally, and which are often associated not with specific observations or [[series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] of data, but with entire collections of data or even the institutions which provide that data.
++The term "metadata" is very broad indeed. A distinction can be made between “structural” metadata – those concepts used in the description and identification of statistical data and metadata – and “reference” metadata – the larger set of concepts that describe and qualify statistical [[data sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] and processing more generally, and which are often associated not with specific observations or [[series>>doc:sdmx:Glossary 2\.1.Series.WebHome]] of data, but with entire collections of data or even the institutions which provide that data.
  The [[SDMX Information Model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]] provides for the structuring not only of data, but also of “reference” metadata. While these [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] structures exist independent of the data and its [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]], they are often linked. The [[SDMX Information Model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]] provides for the attachment of [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] to any part of the data or [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]], as well as for the reporting and exchange of the [[reference metadata>>doc:sdmx:Glossary 2\.1.Reference metadata.WebHome]] and its structural descriptions. This function of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standards supports many aspects of data quality initiatives, allowing as it does for the exchange of metadata in its broadest sense, of which quality-related metadata is a major part.
@@ -197,7 +197,7 @@
  This document specifies the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standards designed to facilitate exchanges based on any of these process patterns, and shows how [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] offers advantages in all cases. It is possible to agree bilaterally to use a standard format (such as [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] or [[SDMX-JSON>>doc:sdmx:Glossary 2\.1.SDMX-JSON.WebHome]]); it is possible for data senders in a gateway process to use a standard format for [[data exchange>>doc:sdmx:Glossary 2\.1.Data exchange.WebHome]] with each other, or with any [[data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] who agree to do so; it is possible to agree to use the full set of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standards to support a common data-sharing process of exchange, whether based on an [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]-conformant registry or some other architecture.
--The standards specified here specifically support a data-sharing process based on the use of central registry services. Registry services provide visibility into the data and metadata existing within the community, and support the access and use of this data and metadata by providing a set of triggers for automated processing. The data or metadata itself is not stored in a central registry – these services merely provide a useful set of metadata about the data (and additional metadata) in a known location, so that users/applications can easily locate and obtain whatever data and/or metadata is registered. The use of standards for all data, metadata, and the registry services themselves is ubiquitous, permitting a high (% style="color:#e74c3c" %)level(%%) of automation within a data-sharing community.
++The standards specified here specifically support a data-sharing process based on the use of central registry services. Registry services provide visibility into the data and metadata existing within the community, and support the access and use of this data and metadata by providing a set of triggers for automated processing. The data or metadata itself is not stored in a central registry – these services merely provide a useful set of metadata about the data (and additional metadata) in a known location, so that users/applications can easily locate and obtain whatever data and/or metadata is registered. The use of standards for all data, metadata, and the registry services themselves is ubiquitous, permitting a high level of automation within a data-sharing community.
  It should be pointed out that these different process models are not mutually exclusive – a single system capable of expressing data and metadata in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]-conformant formats could support all three scenarios. Different standards may be applicable to different processes (for example, many registry services interfaces are used only in a data-sharing scenario) but all have a common basis in a shared information model.