7 Data Reference Model
7.9 DRM Abstract Model
This section presents the DRM abstract model. The DRM abstract model depicts the major concepts from each standardisation area and the relationships between them. It represents an architectural pattern that contains the minimum level of detail necessary to convey the major concepts for the standardisation area, with COIs extending the architectural pattern as necessary for their implementations.
The DRM Abstract Model section is organised as follows:
Contents
- Introduction
- Data Description Section of the DRM Abstract Model
- Data Context Section of the DRM Abstract Model
- Data Sharing Section of the DRM Abstract Model
- Data Sharing Attributes
7.9.1 Introduction
The DRM abstract model is shown in Figure 7-16. The three DRM standardisation areas are arranged in the same general configuration as in Figure 7‑2 (i.e. with the Data Sharing standardisation area on top, supported by the Data Description and Data Context standardisation areas). The following conventions are used:
- Concepts are expressed as boxes, while relationships are expressed as arrows.
- Only 'outbound' relationships are listed (i.e. those that originate from the concept).
- Links between standardisation areas are marked as indicated in the legend and each is provided a circled number intended for reference in the explanation of that link in the table below.
- Cardinality (e.g. one-to-many, many-to-many) is not depicted in the abstract model. Implementations based on the DRM will introduce cardinality as needed according to their requirements.
Subsequent parts of this section will 'drill down' into the details of this abstract model and describe the concepts that comprise each standardisation area's section of the DRM abstract model.
The table on page 254 summarises each of the links between each standardisation area's section of the DRM abstract model. It is intended to help the reader navigate through the DRM abstract model. The following information is provided for each link:
- link number: the circled number from the DRM abstract model that represents the link
- from standardisation area: the standardisation area that is the source of the link
- to standardisation area: the standardisation area that is the destination of the link
- concept: the concept that is common (i.e. linked) between the two standardisation areas.
Figure 7‑16: DRM Abstract Model
click on image to enlarge
| Link Number | From Standardisation Area | To Standardisation Area | Concept |
|---|---|---|---|
| 1 | Data Description | Data Context | Data Asset |
| 2 | Data Context | Data Description | Digital Data Resource |
| 3 | Data Context | Data Description | Query Point |
| 4 | Data Context | Data Sharing | Exchange Package |
| 5 | Data Context | Data Description | Structured Data Resource |
| 6 | Data Sharing | Data Context | Data Asset |
| 7 | Data Sharing | Data Description | Entity |
The concepts that comprise each standardisation area will now be described in detail.
7.9.2 Data Description Section of the DRM Abstract Model
The Data Description section of the DRM abstract model is shown in Figure 7‑17. Links between this standardisation and other standardisation areas are indicated by the link number that corresponds to the link number in the DRM abstract model.
Figure 7‑17: DRM Data Description Abstract Model
The following are definitions for each of the concepts and relationships shown above.
The following conventions are used:
- The concepts are presented in an order that will ensure the best possible understanding and specific examples are provided where appropriate.
- Though cardinality is not expressed in the figure, the descriptions below may include cardinality (e.g. 'one or more') for purposes of clarity. Each concept will be referred to in a quantity of one (e.g. 'An Entity contains an Attribute') for purposes of simplicity.
- Concept names will be capitalised as in the figure itself (e.g. 'Digital Data Resource'), while relationship names will be expressed in italics and without any hyphens that may appear in the relationship name in the figure (e.g. 'is constrained by'). This is done so that the definitions below can take on as narrative a tone as possible. The reader should therefore be able to easily visually navigate through the figure as they read the definitions below.
| Term | Definition |
|---|---|
| Data Schema | A Data Schema is a representation of metadata, often in the form of data artefacts such as logical data models or conceptual data models. The Data Schema concept is actually a concept group, which is an aggregation of related concepts. The Data Schema concept group is comprised of those concepts pertaining to the representation of structured data. Relationships:
|
| Entity | An Entity is an abstraction for a person, place, object, event or concept
described (or characterised) by common Attributes. For example,
'Person' and 'Agency' are Entities. An instance of an Entity represents Relationships:
|
| Data Type | A Data Type is a constraint on the type of data that an instance of an Attribute may hold (e.g. 'string' or 'integer'). Relationships:
|
| Attribute | An attribute is a characteristic of an Entity whose value may be used to help distinguish one instance of an Entity from other instances of the same Entity. For example, an Attribute of a 'Person' Entity may be 'Social Security Number (SSN)'. An SSN is used to distinguish one person (i.e. one instance of a 'Person' Entity) from another. Relationships:
|
| Relationship | This describes the relationship 40 between two Entities. Relationships:
Example: a 'Person' Entity may have a Relationship with an 'Agency' Entity of 'works for'. |
| Digital Data Resource | A Digital Data Resource is a digital container of information, typically known as a file. A Digital Data Resource may be one of three specific types of data resources, each corresponding to one of the three types of data described earlier and each described below (see 'Structured Data Resource', 'Semi-Structured Data Resource', and 'Unstructured Data Resource'). Relationships:
|
| Structured Data Resource |
A Structured Data Resource is a Digital Data Resource containing structured data. Relationships:
|
| Semi-Structured Data Resource |
A Semi-Structured Data Resource is a Digital Data Resource containing semi-structured data. Relationships:
|
| Unstructured Data Resource |
An Unstructured Data Resource is a Digital Data Resource containing unstructured data. Relationships:
|
| Document | A Document is a file containing Unstructured and/or Semi-Structured Data Resources. Relationships:
Example (relationship with Entity): a query that states 'Find all Documents in which the following person is referenced'. Note: While a Document can contain structured data, it normally has explanatory material included, which would cause it to therefore be considered semi-structured. It is for this reason that there is no 'contains' relationship from Document to Structured Data Resource. It is very important to separate Documents from Structured Data Resources because they are processed very differently. The difference between a Document and a Digital Data Resource, therefore, is that a Digital Data Resource can contain structured data. |
The table below provides attributes41 that are associated with each concept in
the Data Description section of the DRM abstract model. A description will be
given for each attribute, along with an example where necessary for clarity. All
Unstructured Data Resource attributes and their descriptions are taken from
the National Archives of Australia's AGLS Metadata Element Set.
All references to 'resource' within descriptions of Unstructured Data Resource should
therefore be interpreted as 'Unstructured Data Resource'. The above URL provides
additional information on attribute descriptions and usage.
| Concept | Attribute | Description | Example |
|---|---|---|---|
| Entity | Identifier42 | A unique string associated with an Entity for identification purposes | '200XCB' |
| Name | The name of an Entity | 'Person' | |
| Description | A description of an Entity | ||
| Data Type | Name | The name of a Data Type | 'string' |
| Description | A description of a Data Type | ||
| Attribute | Name | The name of an Attribute | 'Date Of Birth' |
| Description | A description of an Attribute | ||
| Relationship | Name | The name of a Relationship | 'works-for' |
| Origin | Name of the concept that is the origin (i.e. the 'from' concept) of a Relationship |
||
| Destination | Name of the concept that is the destination (i.e. the 'to' concept) of a Relationship |
||
| Digital Data Resource |
See 'Structured Data Resource', 'Semi-Structured Data Resource', and 'Unstructured Data Resource' 43 |
||
| Structured Data Resource |
See all concepts within 'Data Schema' group | ||
| Semi-Structured Data Resource |
See 'Structured Data Resource' and 'Unstructured Data Resource' | ||
| Unstructured Data Resource |
Title | A name given to the resource. Typically, the name by which the resource is formally known. | 'The Mortimer Report' |
| Resource Identifier |
An unambiguous reference to the resource within a given context. | '200XCB' | |
| Date | A date of an event in the lifecycle of the resource. Typically, Date will be associated with the creation or availability of the resource. | '2001-05-01' | |
| Creator | An entity primarily responsible for making the content of the resource. Examples of a Creator include a person or an organisation. | 'corporateName= Family Law Council;jurisdiction =Commonwealth of Australia' |
|
| Format | The physical or digital manifestation of the resource. Typically, Format may include the media-type or dimensions of the resource. Format may be used to determine the software, hardware or other equipment needed to display or operate the resource. | '650 megabytes; 72 minutes' |
|
| Description | An account of the content of the resource. Description may include but is not limited to: an abstract, table of contents, reference to a graphical representation of content (e.g. a thumbnail of an image) or a free-text account of the content. | 'This site provides information for parents on the location of child care services.' |
|
| Source | A reference to a resource from which the present resource is derived. The present resource may be derived from the Source resource in whole or in part. | 'ISBN 0 55555 0000' |
|
| Subject | A subject and/or topic of the content of the resource. Typically, a Subject will be expressed as keywords, key phrases or classification codes that describe a topic of the resource content. | 'Health Thesaurus' | |
| Resource Type | The nature or genre of the content of the resource. Type includes terms describing general categories, genres or aggregation levels for content. | 'Service' | |
| Publisher | An entity responsible for making the resource available. This field is often the name of the organisation that owns or controls or publishes the resource. | 'corporateName=High Court;jurisdiction= Commonwealth of Australia' |
|
| Contributor | An entity responsible for making a contribution to the content of the resource. Typically, a contributor will be an entity that has played an important but secondary role in creating the content of the resource and is not specified in the creator element. | 'corporateName= WebDesign; e-mail=webdesign@ hereweare.com.au' |
|
| Language | A language of the
intellectual content
of the resource. Recommended best practice for the values of the Language element is defined by RFC 3066 [RFC 3066] which includes a two-letter Language Code (taken from the ISO 639 standard [ISO 639]), followed optionally by a two letter Country Code (taken from the ISO 3166 standard [ISO 3166]). |
'fr-CA' | |
| Relation | A reference to a related resource. |
'Standards Australia, Records Management (AS 4390), Homebush, 1996' | |
| Coverage | The extent or scope of the content of the resource. Coverage will typically include spatial location (a place name or geographic coordinates), temporal period (a period label, date, or date range) or jurisdiction (such as a named administrative entity). | 'New South Wales' | |
| Rights Management |
Information about
rights held in and
over the resource.
Typically, the
Rights element will contain a rights management statement for the resource or refer to a service providing such information. |
'Copyright Commonwealth of Australia 2001' |
|
| Availability | How the resource can be obtained or contact information for obtaining the resource. The Availability element is primarily used for non-electronic resources to provide information on how to obtain physical access to the resource. | 'Medical assistance is available by contacting the medical hotline on 1800 123456' | |
| Function | The business function of the organisation to which the resource relates. Used to indicate the business role of the resource in terms of business functions and activities. | 'Community Services' | |
| Audience | A target audience of the resource. Types of audiences commonly used in this element include particular industry sectors, education levels, skill levels, occupations and EEO categories. | 'Upper Primary' | |
| Document | See 'Structured Data Resource' and 'Semi-Structured Data Resource' | ||
7.9.3 Data Context Section of the DRM Abstract Model
The Data Context section of the DRM abstract model is shown in Figure 7‑18 below.
Figure 7‑18: Data Context Section of the DRM Abstract Model
The following are definitions for each of the concepts and relationships shown on the previous page.
| Term | Definition | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Taxonomy | A Taxonomy is a collection of controlled vocabulary terms organised into a hierarchical structure. Taxonomies provide a means for categorising or classifying information within a reasonably well defined associative structure, in which each term in the Taxonomy is in one or more parent/child (broader/narrower) relationships to other terms in the Taxonomy. A common example of a Taxonomy is the hierarchical structure used to classify living things within the biological sciences from Carolus Linnaeus, as shown in the table below.
Relationships:
Example: a taxonomy expressed in W3C Web Ontology Language (OWL) format. |
||||||||||||||||
| Structured Data Resource | See the Data Description section. | ||||||||||||||||
| Topic | A topic is a category within a Taxonomy. A Topic is the central concept for applying context to data. For example, an agency may have a Taxonomy that represents their organisational structure. In such a Taxonomy, each role in the organisational structure (e.g. CIO) represents a Topic. Topic is often synonymous with 'node'. Relationships:
A Topic participates in a Relationship with another Topic. |
||||||||||||||||
| Digital Data Resource | See the Data Description section. | ||||||||||||||||
| Query Point | See the Data Sharing Section | ||||||||||||||||
| Exchange Package | See the Data Sharing section. | ||||||||||||||||
| Relationship | This describes the relationship 45 between two Topics. Relationships:
Example: A 'Person' Entity may be represented in one Data Asset in a 'Customer' context because it is part of a CUSTOMER_INFO table. However, the same Entity may be represented in a 'Suspect' context on a law enforcement website. The metadata that is associated with the 'Person' Entity would be different in each context: for example, the 'Suspect' context would likely include physical characteristic metadata (height, hair colour, etc.), while the 'Customer' context would not. |
||||||||||||||||
| Data Asset | A Data Asset is a managed container for data. In many cases this will be a relational database. However, a Data Asset may also be a website, a document repository, a directory or a data service. Relationships:
Example: A document that is stored and managed within a data asset (such as a document repository) has management context provided for it through the metadata that is associated with that document within the document repository. Such metadata may include the AGLS Metadata Standard attributes that are described in the Data Description section. |
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| Data Steward | A Data Steward is the person responsible for managing a Data Asset. Relationships:
|
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| Other AGA Reference Models | This concept represents the four other AGA reference models: the Business Reference Model (BRM), the Service Reference Model (SRM), the Technical Reference Model (TRM) and the Performance Reference Model (PRM). Its purpose is to provide a linkage to these other reference models, which are themselves Taxonomies. These are depicted as a special kind of Taxonomy due to their importance in the overall classification of information. Relationships:
|
The table below provides attributes that are associated with each concept in the Data Context section of the DRM abstract model.
| Concept | Attribute | Description | Example |
|---|---|---|---|
| Taxonomy | Identifier 46 | A unique string associated with a Taxonomy for identification purposes. | '200XCB' |
| Name | The name of a Taxonomy. | 'Geographic Areas' | |
| Description | A description of a Taxonomy. | ||
| Topic | Name | The name of a Topic. | 'Country' |
| Description | A description of a Topic. | ||
| Relationship | Name | The name of a Relationship. | 'part-of' |
| Origin | Name of the concept that is the origin (i.e. the 'from' concept) of a Relationship. | ||
| Destination | Name of the concept that is the destination (i.e. the 'to' concept) of a Relationship. | ||
| Data Asset | Identifier | A unique string associated with a Data Asset for identification purposes. | '333XBD' |
| Type | Type of Data Asset - e.g. database, website, registry, directory, data service, etc. | 'database' | |
| Geospatial Enabled | Designates whether or not the Data Asset supports or provides Geospatial data. | 'yes' | |
| Data Steward | Employee ID | Data Steward's employee ID. | |
| Department | Department for which the Data Steward works. | ||
| Initial Date | The date that the Data Steward became associated with the Data Asset. | ||
| Other AGA Reference Model | Acronym | Reference model acronym. | 'BRM' |
| Name | Reference model name. | 'Business Reference Model' |
7.9.4 Data Sharing Section of the DRM Abstract Model
The Data Sharing section of the DRM abstract model is shown in Figure 7‑19.
Figure 7‑19: Data Sharing Section of the DRM Abstract Model
The following are definitions for each of the concepts and relationships shown above.
| Term | Definition |
|---|---|
| Exchange Package | An Exchange Package is a description of a specific recurring data exchange between a Supplier and a Consumer. An Exchange Package contains information (metadata) relating to the exchange (such as Supplier ID, Consumer ID, validity period for data, etc.), as well as a reference to the Payload (message content) for the exchange. An Exchange Package can also be used to define the result format for a query that is accepted and processed by a Query Point in a data sharing scenario. Relationships:
Example: an Exchange Package describes a specific recurring data exchange involving shipment information. |
| Entity | See the Data Description chapter. |
| Supplier | A Supplier is an entity (person or organisation) that supplies data to a Consumer. Relationships:
Example: a federal agency that supplies data to one or more other |
| Consumer | A Consumer is an entity (person or organisation) that consumes data that is supplied by a Supplier. Relationships:
Example: an Australian Government agency that consumes data |
| Payload Definition | A Payload Definition is an electronic definition that defines the requirements for the Payload (data) that is exchanged between a Supplier and a Consumer. Relationships:
Example: A specific message set expressed as an XML schema or an EDI transaction set that contains information about a 'Person' entity. |
| Query Point | A Query Point is an endpoint that provides an interface for accessing and querying a Data Asset. A concrete representation of a Query Point may be a specific URL at which a query Web Service may be invoked. Relationships:
Example: a specific URL at which a data service may be invoked. |
| Data Asset | See the Data Context section. |
7.9.5 Data Sharing Attributes
This section will expand on the concepts presented above to include attributes that are associated with each concept. A description will be provided for each attribute, along with an example where necessary for clarity.
| Concept | Attribute | Description | Example |
|---|---|---|---|
| Exchange Package |
Identifier 47 | A unique string associated with an Exchange Package for identification purposes. | '200XCB' |
| Name | The name of an Exchange Package. | 'Bill of Lading Message Set' | |
| Description | A description of an Exchange Package. | ||
| Classification | The security classification for an Exchange Package. | 'U' (Unclassified) | |
| Frequency | The frequency at which the exchange occurs. | 'Daily' | |
| Supplier | Identifier | A unique string associated with a Supplier for identification purposes. | '04091967J' |
| Name | The name of a Supplier. | ||
| Primary Contact | The name and contact information for the Supplier's primary contact for this particular exchange. | ||
| Consumer | Identifier | A unique string associated with a Consumer for identification purposes. | '03081956K' |
| Name | The name of a Consumer. | ||
| Primary Contact | The name and contact information for the Consumer's primary contact for this particular exchange. | ||
| Data Steward | Identifier | A unique string associated with a Payload Definition for identification purposes. | 'B5102078L' |
| Name | The name of a Payload Definition. | 'Bill of Lading XML Schema' | |
| Query Point | Identifier 48 | A unique string associated with a Query Point for identification purposes. | http://www.example.com/ querypoint3 |
| Name | The name of a Query Point. | 'Latest Monthly Report Information' |
|
| Description | A description of a Query Point. | ||
| Query Languages |
A stipulation of the query languages that are supported by a Query Point (e.g. SQL-92, CQL (Z39.50), XQuery, HTTP GET, etc.). | 'SQL-92' |
Footnotes
40 It should be noted that the term 'relationship' is used in two ways here. The concept named 'Relationship' participates in relationships with other concepts in the abstract model and also defines the relationship between entities when it is applied to a specific scenario.
41 It should be noted that the term 'attribute' is used here in a different way than for the concept named 'Attribute'. Here, an 'attribute' is used to describe characteristics of each of the concepts in the abstract model.
42 The 'Identifier' attribute is described at an abstract level in order to be consistent with the abstract nature of the reference model. Therefore, there are no references to aspects such as identifier uniqueness, representation format or similar. Implementations based on the DRM will introduce such aspects as needed according to their requirements.
43 As shown in the abstract model, a Digital Data Resource may be one of these three specific types of data resources. The same general idea applies to the entries for the 'Semi-Structured Data Resource' and 'Data Object' concepts above.
44 Because a Taxonomy is represented as a Structured Data Resource and a Data Asset provides management context for a Digital Data Resource, it follows that a Taxonomy may be stored and managed within a Data Asset.
45 It should be noted that the term 'relationship' is used in two ways here. The concept named 'Relationship' participates in relationships with other concepts in the abstract model and also defines the relationship between topics when it is applied to a specific scenario.
46 The 'Identifier' attribute is described at an abstract level in order to be consistent with the abstract nature of the reference model. Therefore, there are no references to aspects such as identifier uniqueness, representation format or similar. Implementations based on the DRM will introduce such aspects as needed according to their requirements.
47 The 'Identifier' attribute is described at an abstract level in order to be consistent with the abstract nature of the reference model. Therefore, there are no references to aspects such as identifier uniqueness, representation format or similar. Implementations based on the DRM will introduce such aspects as needed according to their requirements.
Contact for information on this page: AGA@finance.gov.au