Difference between revisions of "Facet Based Resource Model"

Revision as of 11:13, 21 July 2016 (view source) Luca.frosini (Talk | contribs) (→‎Relation Property) ← Older edit		Revision as of 11:15, 21 July 2016 (view source) Luca.frosini (Talk | contribs) (→‎Dataset) Newer edit →
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	| [[#Identifier_Facet|Identifier]]		| [[#Identifier_Facet|Identifier]]
	| '''TBD'''		| '''TBD'''
		+	|-
		+	| [[#Dataset|Dataset]]
		+	| [[#Contact_Relation|Contact Relation]]
		+	| align=center|1..n
		+	| [[#Contact_Facet|Contact Facet]]
		+	| ...
	|-		|-
	| [[#Dataset|Dataset]]		| [[#Dataset|Dataset]]

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Revision as of 11:15, 21 July 2016

Contents 1 Basic Concepts 1.1 Property 1.1.1 Property Type 1.1.1.1 Basic Property Type 1.1.1.2 Derived Property Type 1.2 Header 2 Facets 2.1 Facets Specification 2.1.1 Access Point Facet 2.1.2 Contact Facet 2.1.3 Coverage Facet 2.1.4 CPU Facet 2.1.5 Descriptive Metadata Facet 2.1.6 Event Facet 2.1.7 Functionality Related Facet 2.1.8 Identifier Facet 2.1.9 Location Facet 2.1.10 Network Address Facet 2.1.11 License Facet 2.1.12 Memory Facet 2.1.13 Peripheral Facet 2.1.14 Provenance Facet 2.1.15 Simple Property Facet 2.1.16 Software Facet 2.1.17 State Facet 2.1.17.1 Service State Facet 2.1.17.2 Container State Facet 2.1.18 Subject Facet 3 Relation 3.1 Relation Property 3.2 RelatedTo 3.2.1 CallFor 3.2.2 ConfiguredBy 3.2.3 CorrelatedTo 3.2.3.1 PartOf 3.2.4 CustomizedBy 3.2.5 Demand 3.2.6 DependOn 3.2.6.1 PluginOf 3.2.7 Discover 3.2.8 Host 3.2.9 Manage 3.2.10 ManagedBy 3.2.11 PoweredBy 3.2.12 Require 3.2.13 Run 3.2.14 Use 3.3 ConsistOf 3.3.1 Identify 3.3.2 Coverage Relation 3.3.2.1 Temporal 3.3.2.2 Spatial 3.3.3 Memory Relation 3.3.3.1 Persistent 3.3.3.2 Volatile 3.3.4 Contact Relation 3.3.4.1 Contributor 3.3.4.2 Creator 3.3.4.3 Curator 3.3.4.4 Developer 3.3.4.5 Manager 3.3.4.6 Owner 4 Resources 4.1 Resource 4.1.1 Actor 4.1.2 Configuration 4.1.3 Dataset 4.1.3.1 Concrete Dataset 4.1.4 Service 4.1.4.1 Abstract Service 4.1.4.2 E-Service 4.1.4.3 Hosting Node 4.1.5 Schema 4.1.6 Site 4.1.7 Software 4.1.8 Plugin 5 Best practices and guidelines 6 Internal Entity and Relation 6.1 Context 6.2 ParentOf

Basic Concepts

• Two typologies of entities are envisaged:
  • Resources, i.e. entities representing a description of "thing" to be managed;
    • Every Resource is characterised by a number of Facets.
  • Facets, i.e. entities contributing to "build" a description of a Resource. Every facet, once attached to a Resource profile captures a certain aspect / characterization of the resource;
    • Every facet is characterised by a number of properties;

• Two typologies of relations are envisaged:
  • RelatedTo, i.e. a relation linking any two Resources.
  • ConsistOf, i.e. a relation connecting each Resource with one of the Facets characterizing it;

• Entities and relations can be specialized.
  • A number of specializations are identified below. Such specializations are managed by the gCube Core services, i.e. Core services builds upon these specialization to realize its management tasks;
  • Other specializations can be defined by clients, the system make it possible to store these additional typologies of relations and facets and to discover them.

• On relations:
  • Any relation has a direction, i.e. a "source" and a "target". Anyway the relation can be also navigated in the opposite direction;
  • It is not permitted to define a Relation having a Facet as "source".
    • It is not permitted to define a Relation connecting a Facet with another one;
    • It is not permitted to define a Relation connecting a Facet with a Resource;
  • A Facet instance can be linked (by ConsistOf or any specialization of it) from different Resources.

Property

Any Property can be enriched with the following attributes:

• Name : Property Name
• Type : The Type of the Property (e.g. String, Integer, ...). See Property Type
• Description : The description of the Property. default=null.
• Mandatory (M): Indicate if the Property is mandatory. default=false.
• ReadOnly (RO): The Property cannot change its value. default=false.
• NotNull (NN): default=false
• Max (Max): default=null
• Min (Min): default=null
• Regexpr (Reg)): A Regular Expression to validate the property value.default=null

Property Type

Basic Property Type

Type	Description	Java type
Boolean	Handles only the values True or False	java.lang.Boolean or boolean
Integer	32-bit signed Integers	java.lang.Integer or int
Short	Small 16-bit signed integers	java.lang.Short or short
Long	Big 64-bit signed integers	java.lang.Long or long
Float	Decimal numbers	java.lang.Float or float
Double	Decimal numbers with high precision	java.lang.Double or double
Datetime	Any date with the precision up to milliseconds.	java.util.Date
String	Any string as alphanumeric sequence of chars	java.lang.String
Binary	Can contain any value as byte array	byte[]
Embedded	The Record is contained inside the owner. The contained Record has no <a href="http://orientdb.com/docs/2.1/Concepts.html#recordid">RecordId</a>	org.gcube.informationsystem.model.embedded.Embedded
Embedded list	The Records are contained inside the owner. The contained records have no <a href="http://orientdb.com/docs/2.1/Concepts.html#recordid">RecordIds</a> and are reachable only by navigating the owner record	List<? extends Embeddedgt;
Embedded set	The Records are contained inside the owner. The contained Records have no <a href="http://orientdb.com/docs/2.1/Concepts.html#recordid">RecordId</a> and are reachable only by navigating the owner record	Set<? extends Embedded>
Embedded map	The Records are contained inside the owner as values of the entries, while the keys can only be Strings. The contained records are reachable only by navigating the owner Record	Map<String, ? extends Embedded>
Link	Link to another Entity.	UUID
Byte	Single byte. Useful to store small 8-bit signed integers	java.lang.Byte or byte
Date	Any date as year, month and day. To know more about it, look at <a href="http://orientdb.com/docs/2.1/Managing-Dates.html">Managing Dates</a>	java.util.Date
Any	Not determinated type, used to specify Collections of mixed type, and null

Derived Property Type

The following are obtained using a String as real type and adding a validation regex.

Type	Description	Java type
Enum	String representation of the Enum. The check enumeration is obtained creating an ad-hoc Regular Expression in the form (FIRST-ENUM-STRING_REPRESENTATION|SECOND-ENUM-STRING_REPRESENTATION|...|LAST_ENUM_STRING_REPRESENTATION).	java.lang.Enum or enum
UUID	String representation of the UUID. The check is obtained using the regular expression ([a-fA-F0-9]{8}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{12}){1}	java.util.UUID
URL	String representation of the URL. The check is obtained using a regex available at https://mathiasbynens.be/demo/url-regex (see diegoperini one).	java.net.URL
URI	String representation of the URI. The check is obtained using .	java.net.URI

Header

Every Entity and Relation has an Header automatically filled by the System. The Header has the following properties:

Name	Type	Description	Attributes
uuid	UUID	This uuid can be used to univocally identify the Entity or the Relation	Mandatory=true NotNull=true ReadOnly=true
creator	String	Filled at creation time. The creator is retrieved using the authorization token	Mandatory=true NotNull=true ReadOnly=true
creationTime	Long	Creation time in milliseconds. Represent the difference, measured in milliseconds, between the creation time and midnight, January 1, 1970 UTC	Mandatory=true NotNull=true ReadOnly=true
lastUpdateTime	Long	Last Update time in milliseconds. Represent the difference, measured in milliseconds, between the last update time and midnight, January 1, 1970 UTC	Mandatory=true NotNull=true

Facets

Early ideas and thinking on facets were documented at 2nd Generation Resource Model : Facets

Facets Specification

Every Facet has:

• An Header
• Zero or more properties. Some of the properties are predefined, but any other property can be added.

Access Point Facet

The goal of this facet is expected to capture information on “access points” for a resource, i.e. any endpoint to interact with the resource via a known protocol.

Name	Type	Description	Attributes
entryName	String	An unique identifier
endpoint	URI	The URI which identify the endpoint of a resource	Mandatory=true ReadOnly=true NotNull=true
protocol	String	The high-level protocol used by the access point. The String could contains the version if needed. E.g. WMS not http which is already contained in URI.
description	String	.....
authorization	String	Contains authorization information. E.g: a token, username:password. By relying on schema it should be sufficient to capture also whether the content is encrypted or not
authorizationSchema	URI	....
properties	String	This can be an arbitrarily complex element whose "structure" is defined by the associated schema
propertiesSchema	URI	....

Contact Facet

The goal of this facet is expected to capture contact information.

Name	Type	Description	Attributes
title	String	e.g. Dr., Mrs, Mr,	Mandatory=false
name	String	First Name	Mandatory=true NotNull=true
middleName	String	Middle Name	Mandatory=false
surname	String	Surname	Mandatory=true NotNull=true
eMail	Email	An RFC‑822 compliant email address.	Mandatory=true NotNull=true Regex see http://www.ex-parrot.com/~pdw/Mail-RFC822-Address.html
website	URL	The main website
address	String	A physical address
phone	String	A phone number

Coverage Facet

The goal of this facet is to collect any extent-related information.

Name	Type	Description	Attributes
value	String	...	Mandatory=true NotNull=true
schema	URI	...	Mandatory=true NotNull=true

CPU Facet

The goal of this facet is to describe CPU information.

Name	Type	Description	Attributes
model	String	...	Mandatory=true NotNull=true
vendor	String	...	Mandatory=true NotNull=true
clockSpeed	String	...	Mandatory=true NotNull=true

Descriptive Metadata Facet

The goal of this facet is to collect any descriptive metadata about the resource.

Name	Type	Description	Attributes
value	String	Inherited. E.g. XML Blob	Mandatory=true NotNull=true
schema	URI	...	Mandatory=true NotNull=true

Event Facet

The goal of this facet is to collect any descriptive metadata about the resource.

Name	Type	Description	Attributes
value	String	...	Mandatory=true NotNull=true
schema	URI	...	Mandatory=true NotNull=true

Functionality Related Facet

The goal of this facet is to capture what are the facilities supported (Challenging because of the different audiences) Something very "poor" ... we can have a look at WPS spec

Name	Type	Description	Attributes
name	String	...
description	String	...
input	String	...
output	String	...

Identifier Facet

The goal of this facet is to collect information on Identifiers that can be attached to a resource.

Name	Type	Description	Attributes
value	String	The identifier. E.g. http://fr.dbpedia.org/resource/Thunnus de305d54-75b4-431b-adb2-eb6b9e546014	Mandatory=true NotNull=true
type	Enumeration	The typology of identifier. I.e. URI, DOI, IRI, URL, URN, UUID;	Mandatory=true NotNull=true
isPersistent	boolean	To indicate if the Identifier is persistent or not.	Mandatory=true NotNull=true

Location Facet

The goal of this facet is to collect information about Location

Name	Type	Description	Attributes
Country	String	...
Location	String	...
Latitude	String	...
Longitude	String	...

Network Address Facet

The goal of this facet is to capture IP information

Name	Type	Description	Attributes
hostName	String	...
domainName	String	...
IPAddress	String	...	Mandatory=true NotNull=true
mask	String	...
broadcastAddress	String	...

Regular expression to validate different IPv4 addresses are available at:

http://www.regextester.com/22

https://www.safaribooksonline.com/library/view/regular-expressions-cookbook/9780596802837/ch07s16.html

Both IPv4 and IPv6: http://stackoverflow.com/questions/53497/regular-expression-that-matches-valid-ipv6-addresses

License Facet

Name	Type	Description	Attributes
name	String	E.g. EUPL 1.1, GPLv2, BSD, ...	Mandatory=true NotNull=true
text	URL	Licence URL	Mandatory=true NotNull=true

Memory Facet

The goal of this facet is to .....

Name	Type	Description	Attributes
size	Long	...	Mandatory=true NotNull=true
used	Long	...	Mandatory=true NotNull=true
unit	String	...	Mandatory=true NotNull=true

Peripheral Facet

The goal of this facet is to .....

Name	Type	Description	Attributes
model	String	...
vendor	String	...

Provenance Facet

The goal of this facet is to collect information related with resource lineage/provenance

Name	Type	Description	Attributes
relationship	Enum	wasGeneratedBy | ...
reference	String	resourceID (a reference to the "originator" Resource associated to the resource the facet is attached to by the relationship)
provenanceDocument	String	... E.g. the xml format
provenanceDocumentSchema	String	... E.g. a reference to the format

Simple Property Facet

The goal of this facet is the base class for all facets described by a value and the schema of the value

Name	Type	Description	Attributes
name	String	...	Mandatory=true NotNull=true
value	String	...	Mandatory=true NotNull=true

Software Facet

The goal of this facet is to capture SW related features"

Name	Type	Description	Attributes
name	String	The name of the software artefact being described. E.g. artifactId in maven, Service Name in gCube software, the software name for retail software Microsoft Office 2013-SP2.
group	String	The name of "group" the software artefact belongs to. E.g. groupId in Maven, ServiceClass in gCube software, company name for retail software Microsoft Office 2013-SP2.
version	String	The particular release of the software artefact. E.g. maven version, Service Version in gCube software, artifactId in maven, the software version for retail software Microsoft Office 2013-SP2.
description	String	A human oriented description of the software artefact being described.
qualifier	String	E.g. packaging or scope in maven, scope level or sharable level in gCube software, target architecture for retail software x86 or amd64.
optional	Boolean	.... Used in maven and in gcube

State Facet

The goal of this facet is to ...

Name	Type	Description	Attributes
value	String	The value of the state. Must be compliant with schema.	Mandatory=true NotNull=true

Service State Facet

Name	Type	Description	Attributes
value	String	The value of the state	Mandatory=true NotNull=true Regex=(STARTED|ready|down|failed)

Container State Facet

Name	Type	Description	Attributes
value	String	The value of the state	Mandatory=true NotNull=true Regex=(started|ready|certified|down|failed)

Subject Facet

The goal of this facet is to ...

Name	Type	Description	Attributes
value	String	The value of the state. Must be compliant with schema.	Mandatory=true NotNull=true
schema	URI	The URI of the schema. It is only an informative field. It is not used for validation from IS part.	Mandatory=true NotNull=true

Relation

Every Facet has:

• An Header
• A Relation Property
• Zero or More properties (not necessarily predefined) similarly to facet.

Relation Property

Name	Type	Description
referentialIntegrity	Enum	I.e. onDeleteCascadeWhenOrphan, onDeleteCascade, onDeleteKeep. The meaning is related to the relation direction.
accessPolicy	Embedded (i.e. AccessPolicy)	A policy is characterized by a name, a description, and the period ([start], [end]) when the policies apply
expiryTime	Long	The expiry date can be used to model the time until the relationship is valid, Expiry time in milliseconds. Represent the difference, measured in milliseconds, between the creation time and midnight, January 1, 1970 UTC

RelatedTo

The following relations have been identified and defined:

CallFor

Service to Service

ConfiguredBy

Software to Configuration

CorrelatedTo

Dataset to Dataset

PartOf

Concrete Dataset to Dataset

CustomizedBy

Service to Configuration

Demand

Abstract Service to Software

DependOn

Software to Software

PluginOf

Plugin to Software

Discover

E-Service to E-Service

Host

Hosting Node to E-Service

Manage

Service to Dataset

ManagedBy

Hosting Node to Site

PoweredBy

Hosting Node to Software

Require

Software to Service

Run

Run E-Service to Software

Use

E-Service to E-Service

ConsistOf

The following relations (extending the ConsistOf) have been identified and defined:

Identify

Resource to Facet

Coverage Relation

Abstract Resource to Coverage

Temporal

Resource to Coverage

Spatial

Resource to Coverage

Memory Relation

Abstract Resource to Memory

Persistent

Resource to Memory

Volatile

Resource to Memory

Contact Relation

Abstract Resource to Contact

Contributor

Resource to Contact

Creator

Resource to Contact

Curator

Resource to Contact

Developer

Resource to Contact

Manager

Resource to Contact

Owner

Resource to Contact

Resources

Every Resource has:

• An Header
• One or More relation with Facets
• Zero or More relation with other Resources

A class can be identified as Abstract. This means that cannot be instantiated. Use specialization instead. It is not required that an Abstract class establish an Identify relation with a Facet.

Resource

Abstract Resource Profile

This entity is conceived to describe every "main thing" to be registered and discovered by the Information System.
Source	Relation	Multiplicity	Target	Description
Facets
Resource	Identify	1..n	Facet	Any Resource has at least one Facet which in some way allow to identify the Resource per se.
Resource	ConsistOf	0..n	Facet	Any Resource consist of zero or more Facets which describes the different aspects of the facet.
Resources
Resource	RelatedTo	0..n	Resource	Any Resource can be related to any other resource.

The following Resources have been identified:

• Actor
• Configuration
• Dataset
  • Concrete Dataset
• Service
  • Abstract Service
  • E-Service
  • Hosting Node
• Software

Actor

Actor Profile

Source	Relation	Multiplicity	Target	Description
Facets
Actor	Identify	1..n	Contact	An Actor has at least a Contact Facet which permit to identify the Actor per se.
Actor	ConsistOf	0..n	Contact	An Actor can have other Contact Facets which provide secondary contact information.
Resources
Actor	RelatedTo	0..n	TBD	TBD

Configuration

Configuration Profile

Source	Relation	Multiplicity	Target	Description
Facets
Configuration	Identify	1..n	Simple Property	TBD
Configuration	ConsistOf	0..n	Facet	TBD
Resources
Software	ConfiguredBy	0..n	Configuration	TBD
Service	CustomizedBy	0..n	Configuration	TBD

Dataset

Dataset Profile

Source	Relation	Multiplicity	Target	Description
Facets
Dataset	Identify	1..n	Identifier	TBD
Dataset	Contact Relation	1..n	Contact Facet	...
Dataset	Curator	0..n	Contact Facet	Is he the curator
Dataset	Owner	0..n	Contact Facet	Is he the owner
Dataset	Creator	0..n	Contact Facet	Is he the creator
Dataset	Contributor	0..n	Contact Facet	Is he the contributor
Dataset	Maintainer	0..n	Contact Facet	Is he the maintainer
Dataset	ConsistOf	0..n	Access Point Facet	The embargoState can be modeled through the access policy defined in the ConsistOf relation
Dataset	ConsistOf	0..n	License Facet	The duration of license if any can can be modeled through the expiry date defined in the ConsistOf relation
Dataset	ConsistOf	0..n	Event Facet	TBD
Dataset	ConsistOf	0..n	Provenance Facet	TBD
Dataset	Temporal	0..n	Coverage	TBD
Dataset	Spatial	0..n	Coverage	TBD
Dataset	ConsistOf	0..n	Descriptive Metadata	TBD
Dataset	ConsistOf	0..n	Subject	TBD
Resources
Service	Manage	0..n	Dataset	TBD
Dataset	CorrelatedTo	0..n	Dataset	TBD
Concrete Dataset	PartOf	0..n	Dataset	TBD

Concrete Dataset

Concrete Dataset Profile extends Dataset Profile

Source	Relation	Multiplicity	Target	Description
Facets
Concrete Dataset	Maintainer	1..n	Contact Facet	Is he the maintainer
Concrete Dataset	ConsistOf	1..n	Access Point Facet	The embargoState can be modeled through the access policy defined in the ConsistOf relation
Resources
Concrete Dataset	PartOf	0..n	Dataset	TBD

Service

Abstract Service Profile

Source	Relation	Multiplicity	Target	Description
Facets
Service	ConsistOf	0..n	Contact Facet	TBD
Resources
Software	Require	0..n	Service	TBD
Service	CallFor	0..n	Service	TBD
Service	CustomizedBy	0..n	Configuration	TBD
Service	Manage	0..n	Dataset	TBD

Abstract Service

Abstract Service Profile extends Service Profile

Source	Relation	Multiplicity	Target	Description
Facets
Abstract Service	Identify	1..n	TBD	TBD
Abstract Service	ConsistOf	0..n	TBD	TBD
Resources
Abstract Service	Demand	0..n	Software	TBD

E-Service

E-Service Profile extends Service Profile

Source	Relation	Multiplicity	Target	Description
Facets
E-Service	Identify	1..1	Software	TBD
E-Service	ConsistOf	1..n	Access Point	Identify the endpoints of the E-Service
E-Service	ConsistOf	1..n	Event	E.g. ActivationTime,DeploymenTime)
E-Service	ConsistOf	1..1	Service State	I.e. STARTED, ready, down, failed
Resources
E-Service	Run	0..n	Software	TBD
E-Service	Use	0..n	E-Service	A reference to any other E-Service, the E-Service instance is invoking.
E-Service	Discover	0..n	E-Service	A reference to any other E-Service, the E-Service instance is discovering through query on IS.
Hosting Node	Host	0..n	E-Service	TBD

Hosting Node

Hosting Node Profile extends Service Profile

Source	Relation	Multiplicity	Target	Description
Facets
Hosting Node	ConsistOf	1..n	CPU Facet	CPU Information
Hosting Node	ConsistOf	1..n	Persistent Memory Facet	Disk Space TBD Specialize ConsistOf
Hosting Node	ConsistOf	1..n	Volatile Memory Facet	RAM TBD Specialize ConsistOf
Hosting Node	ConsistOf	1..n	Network Address	Network address
Hosting Node	ConsistOf	1..n	Event	TBD
Hosting Node	ConsistOf	1..n	Container State	I.e. started, ready, certified, down, failed
Hosting Node	ConsistOf	1..n	Simple Property	E.g. Environment Variables
Resources
Hosting Node	Host	0..n	E-Service	A reference to any E-Service instance, the Hosting Node instance is hosting.
Hosting Node	ManagedBy	0..n	Site	TBD
Hosting Node	PoweredBy	0..n	Software	TBD

Schema

TBD

Schema Profile

Source	Relation	Multiplicity	Target	Description
Facets
Schema	Identify	1..n	Identification	TBD
Schema	ConsistOf	1..n	TBD	TBD
Resources
Schema	TBD	0..n	TBD	TBD

Site

Site Profile

Source	Relation	Multiplicity	Target	Description
Facets
Site	Identify	1..n	Identification	TBD
Site	ConsistOf	1..n	Contact Facet	TBD
Site	ConsistOf	1..n	Location Facet	TBD
Hosting Node	ConsistOf	1..n	Network Address	Network address TBD
Resources
Hosting Node	ManagedBy	0..n	Site	TBD

Software

Software Profile

Source	Relation	Multiplicity	Target	Description
Facets
Software	Identify	1..n	Software	Software coordinates which identify the Software per se.
Software	ConsistOf	1..n	Software	Apart the one connected with Identify relation (gCube coordinates) the others identify the sw in other way e.g. (Maven coordinates)
Software	ConsistOf	0..n TBD	Access Point	Links to maven artifact on nexus, javadoc, wiki, svn ...
Software	ConsistOf	0..n TBD	License	TBD
Software	ConsistOf	1..n	State	TBD
Resources
Software	ConfiguredBy	0..n	Configuration	TBD
Software	DependOn	0..n	Software	TBD
Software	Require	0..n	Service	TBD
Plugin	PluginOf	0..n	Software	TBD
Abstract Service	Demand	0..n	Software	An inverse reference stemming from the Abstract Service that is ...
E-Service	Run	0..n	Software	An inverse reference stemming from the E-Service that is running this Software
Hosting Node	PoweredBy	0..n	Software	An inverse reference stemming from the Hosting Node that is ...

Plugin

Plugin Profile extends Software Profile

Source	Relation	Multiplicity	Target	Description
Facets
Plugin	TBD	TBD	TBD	TBD
Resources
Plugin	PluginOf	1..n	Software	A reference to the Software this Plugin extends capabilities.

Best practices and guidelines

• On Facet instances "reuse" across Resource Profiles:
  • This can be guaranteed automatically by the system, if and just in the case the system want to avoid duplication of information. It is based on a configuration policy;
  • This MUST be done only when a change in a facet instance MUST affect a change in all Resources connected to such a Facet.

Internal Entity and Relation

For internal use only are defined the following entity and relation:

• Context
• ParentOf

Context

Model a Context (aka scope)

ParentOf

A relation beetween two Context