OS MasterMap Highways Network – Paths Technical Specification

This technical specification provides detailed technical information about OS MasterMap Highways Network – Paths. It is targeted at technical users and software developers.

OS MasterMap Highways Network is the authoritative highway network for Great Britain. It brings together Ordnance Survey’s large-scale roads and paths content, the National Street Gazetteer (NSG), the Trunk Road Street Gazetteer (TRSG), and the Scottish Street Gazetteer (SSG).

OS MasterMap Highways Network is made up of four product schemas: Linear Highway Network, Highways Dedication, Routing and Asset Management Information and Highways Water Transport Network. These four schemas create the following three products which are a part of the OS MasterMap Highways Network family:

• OS MasterMap Highways Network – Roads

• OS MasterMap Highways Network – Routing and Asset Management Information (RAMI)

• OS MasterMap Highways Network – Paths

This technical specification will cover the OS MasterMap Highways Network – Paths (from here referred to as Path Network) product specification. For details on the Roads or RAMI products' specifications, see their respective Technical Specifications.

The conceptual INSPIRE Transport Network Model. OS MasterMap Highways will include the Linear Network, RAMI and the Water Transport Network within the Generic Network Model.

Identifiers

All features that comprise the OS MasterMap Highways Network – Paths will be assigned a persistent identifier; in most instances this is an Ordnance Survey TOID (Topographic Identifier). For features which have originated from the National Street Gazetteer, the persistent identifier will be either a Unique Street Reference Number (USRN) for Street features or a unique ID for Maintenance, Reinstatement, Special Designation and Highway Dedication.

Identifiers shall be encoded in three properties in the data:

1. gml:id – This is a feature identifier comprised of the shorthand prefix namespace and local identifier which is used to uniquely identify and reference the feature within the dataset.

Example: osgb4000000009461245

1. gml:identifier – This is a global feature identifier and can be used to identify and reference the feature within other datasets. Example: http://data.os.uk/id/4000000009461245

2. inspireID – This is a complex property made up of a localId, namespace and versionId which uniquely identifies the feature and version within an INSPIRE dataset. The versionId will not be populated in the OS MasterMap Highways Network products.

<highway:Road gml:id="osgb4000000009461245">
    <gml:identifier codeSpace="http://inspire.jrc.ec.europa.eu/ids">
http://data.os.uk/id/4000000009461245
</gml:identifier>
<net:beginLifespanVersion>2010-04-01T00:00:00.000</net:beginLifespanVersion>
<net:inspireId>
    <base:Identifier>
    <base:localId>4000000009461245</base:localId>
    <base:namespace>http://data.os.uk/</base:namespace>
        <base:versionId>16</base:versionId>
    </base:Identifier>
</net:inspireId>

Where features have come from OS MasterMap ITN Layer the identifier will be persistent and correspond to the same feature in ITN.

The gml:id is used throughout the OS MasterMap Highways Network products as the identifier used to reference to other features.

TOIDs

TOIDs (Topographic Identifiers) are strings of up to 20 characters which consist of 2 parts:

• Namespace – This is either a HTTP URI (http://data.os.uk/) or shorthand prefix (‘osgb’)

• Local identifier – 16-digit numeric string (0–9)

Examples:

• gml:id – ‘osgb4000000009461245’

• localId – ‘4000000009461245’

• identifier - ‘http://data.os.uk/4000000009461245’

USRNs

USRNs (Unique Street Reference Numbers) are strings of up to 12 characters which consist of 2 parts:

• Namespace – This is either a HTTP URI (http://data.os.uk/) or shorthand prefix (‘usrn’)

• Local identifier – Up to an 8-digit numeric string (0–9)

Examples:

• gml:id – ‘usrn82101225’

• localId – ‘82101225’

• identifier – ‘http://data.os.uk/82101225’

Although the gml:id is the identifier used for referencing to features in OS MasterMap Highways Network products the localId is the identifier used by the National Street Gazetteer, National Land and Property Gazetteer and the OS AddressBase family of products.

Unique IDs

Unique IDs for Maintenance, Reinstatement, Special Designation are strings of up to seventeen characters which consist of two parts:

• Namespace – This is either a HTTP URI (http://data.os.uk/) or shorthand prefix (‘id_’)

• Local identifier – 14 alphanumeric string

The ID for HighwayDedication is a string of up to 25 characters comprised of the characters “esu” followed by three parts separated by “_”:

• LHA authority code

• ESU it references

• dedication code in the NSG

Example: esu4720_4280330430163_8, esu4720_4280340431456_11

Examples given for both unique ID formats:

• gml:id – ‘id_3700MA01862142’ or ‘esu4720_4280330430163_8’

• localId – ‘3700MA01862142’ or ‘esu4720_4280330430163_8’

• identifier – ‘http://data.os.uk/3700MA01862142’ or ‘https://data.os.uk/id/ esu4720_4280330430163_8’

Available formats

OS MasterMap Highways Network– Paths is supplied in three formats: Geography Markup Language (GML 3.2.1), GeoPackage and vector tiles. All formats are compressed into a regular zip file (.ZIP).

Adherence to standards

• OS MasterMap Highways Network extends the INSPIRE Transport Networks (Road and Water) Technical Specification (version 3.2).

• OS MasterMap Generic Network model extends the INSPIRE Base Models - Generic Network Model (version 3.0rc3).

Extending the INSPIRE Specification

OS MasterMap Highways Network extends the INSPIRE specification to include the additional properties required by BS 7666-1:2006 defined within the National Street Gazetteer (NSG) Data Transfer Format (DTF) and Scottish DTF (SDTF) to ensure that conformance to both INSPIRE and BS7666-1:2006 can be achieved.

Notation

UML diagram and table conventions

The data structure is described by means of UML class diagrams and accompanying data dictionary tables. The specification conforms to the rules for application schema specified in ISO 19103 Conceptual schema language and ISO 19109 Rules for application schema, as adopted by INSPIRE.

Colour conventions have been used in the diagrams and tables to allow users to easily distinguish the INSPIRE feature classes (coloured grey) from the Ordnance Survey feature classes which extends the INSPIRE specifications (coloured orange). All code lists classes are coloured blue, enumeration classes are green and data types/union classes are purple.

Colour conventions used in the UML diagrams

The data dictionary tables use orange for a feature type; blue for a code list; green for enumerations and purple for data types.

Lexical conventions

1. Class names are conceptually meaningful names (singular noun) in UpperCamelCase.

2. Class names end in “Value” where the class is assigned the stereotype <<CodeList>> or <<Enumeration>>.

3. Class names shall end in “Type” where the class is assigned the stereotype <<DataType>>.

4. Property names (attributes and associations) are in lowerCamelCase.

Stereotypes

The following stereotypes are used on UML elements:

Stereotype	UML Element	Description
<<ApplicationSchema>>	Package	Parent package containing sub-packages and elements that comprise part of the modular specification.
<<FeatureType>>	Class	A spatial object type [ISO 19136].
<<Type>>	Class	A structured data type with identity.
<<DataType>>	Class	A structured data type without identity [ISO/TS 19103].
<<Union>>	Class	A structured data type without identity where exactly one of the properties of the type is present in any instance.
<<Enumeration>>	Class	A fixed controlled set of values for a free text data type.
<<CodeList>>	Class	A controlled set of values for a free text data type that may be extended.
<<Voidable>>	Property	A property that is required but is either not currently captured (unknown) or is partially populated (unpopulated).
<<LifecycleInfo>>	Property	Property considered part of the life cycle information.

Constraints

Constraints are defined on the Class using human readable language only. Constraints are displayed on class diagrams. These constraints are used to define co-constraints or restrict INSPIRE properties only.

Representation of constraints in UML diagrams

Relationships and associations

There are three key types of relationship defined between classes:

• Generalisation/Specialisation: This is used to denote either:

  • An extension relationship: where the target class represents the same real-world entity and is extending it to include additional properties not defined on the parent class.

  • A sub-typing relationship. The target class defined a specialised sub-type of parent feature. For example, TransportNode is a specialised sub-type of a generic Node class.

This class has the same name as the class it is extending.

• Directed Association: Used to denote relationships between features. These relationships are encoded as references to the related feature via the identifier assigned in the gml:id. The directed end shall be assigned a name which describes the relationship between the two features and a multiplicity.

• Aggregation: These denote part-of relationships. Aggregations are used to describe loose part-of relationships. If the parent feature ceases to exist then the part feature can continue to exist. For example, a Road Name may cease to exist, but the Road will still exist.

Relationships between feature types

Index

This technical specification includes the following sections:

• Specification changes

• Structure

• How does the product fit together?

• Change-Only Update Supply

• Feature types

• Structured data types

• Data types

• Code lists and Enumerations

• GML Overview

• GeoPackage overview

• Vector tiles overview

• GML examples