Road-Segment.md

Road Segment

This entity contains a harmonised geographic and contextual description of a RoadSegment. A collection of RoadSegments are used to describe a Road. This entity is primarily associated with the Automotive and Smart City vertical segments and related IoT applications.

Attribute Name	Attribute Type	Description	Constraint
id	@id	Provides a unique identifier for an instance of the entity either in the form of a URI (i.e. either a publicly accessible URL or a URN).	Mandatory
type	@type	Defines the type of the entity.	Mandatory
createdAt	TemporalProperty	Indicates the date/ time that the instance of the entity was created in ISO 8601 format. The value of this will be set by the server when the entity was created.	Mandatory
modifiedAt	TemporalProperty	Indicates the date/ time when the entity was last modified in ISO 8601 format. The value of this will be set by the server when the entity was modified, if the entity has not been modified it may have a null value.	Optional
source	Property	Specifies the URL to the source of this data (either organisation or where relevant more specific source)	Recommended
dataProvider	Property	Specifies the URL to information about the provider of this information	Recommended
entityVersion	Property	The entity specification version as a number. A version number of 2.0 or later denotes the entity is represented using NGSI-LD	Recommended
road	Relationship	Refers to the Road entity that this RoadSegment relates to.	Recommended
startPoint	GeoProperty	The geo:json encoded start point for this RoadSegment.	Mandatory
endPoint	GeoProperty	The geo:json encoded end point for this RoadSegment.	Mandatory
relatedSegments	Relationship	Refers to related RoadSegment entities e.g. adjoining, junctions, opposite carriageway.	Recommended
roadClass	Property	The official classification of this road (relevant to the local country).	Recommended
name	Property	The name for this road segment.	Recommended
path	GeoProperty	The geo:json sequence of points that make up this RoadSegment (as a LineString).	Recommended
POIs	Relationship	A reference to associated Points of Interest (e.g. service station) that are connected with this RoadSegment.	Recommended

NGSI-LD Context Definition

The following NGSI-LD context definition applies to the Road Segment entity

Download context definition.

{
    "@context": {
        "source": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/source",
        "dataProvider": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/dataprovider",
        "entityVersion": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/entityversion",
        "road": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/road",
        "startPoint": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/startpoint",
        "endPoint": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/endpoint",
        "relatedSegments": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/relatedsegments",
        "roadClass": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/roadclass",
        "name": "https://schema.org/name",
        "path": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/path",
        "POIs": "https://www.gsma.com/iot/iot-big-data/ngsi-ld/pois"
    }
}

Example of Road Segment Entity

The following is an example instance of the Road Segment entity

Download example entity definition.

{
    "@context": [
        "https://forge.etsi.org/gitlab/NGSI-LD/NGSI-LD/raw/master/coreContext/ngsi-ld-core-context.json",
        "https://raw.githubusercontent.com/GSMADeveloper/NGSI-LD-Entities/master/examples/Road-Segment-context.jsonld"
    ],
    "id": "urn:ngsi-ld:RoadSegment:27109fe0-0c60-4302-a9eb-e7065eca876e",
    "type": "RoadSegment",
    "createdAt": "2017-01-01T01:20:00Z",
    "modifiedAt": "2017-05-04T12:30:00Z",
    "source": "https://source.example.com",
    "dataProvider": "https://provider.example.com",
    "entityVersion": 2.0,
    "road": {
        "type": "Relationship",
        "object": "urn:ngsi-ld:Road:19b6f4b7-a9b4-4114-8391-3133bf96aedc"
    },
    "startPoint": {
        "type": "GeoProperty",
        "value": {
            "type": "Point",
            "coordinates": [
                52.026536,
                0.603404
            ]
        }
    },
    "endPoint": {
        "type": "GeoProperty",
        "value": {
            "type": "Point",
            "coordinates": [
                52.058727,
                0.700214
            ]
        }
    },
    "relatedSegments": {
        "type": "Relationship",
        "object": [
            "urn:ngsi-ld:RoadSegment:75460f68-5911-11e8-abc1-2f5262349650",
            "urn:ngsi-ld:RoadSegment:7b2c9d70-5911-11e8-8484-7704bd54bf6b"
        ]
    },
    "roadClass": {
        "type": "Property",
        "value": "Motorway"
    },
    "name": {
        "type": "Property",
        "value": "M1 J13 to J14"
    },
    "path": {
        "type": "GeoProperty",
        "value": {
            "type": "LineString",
            "coordinates": [
                [
                    52.026536,
                    0.603404
                ],
                [
                    52.034828,
                    0.637166
                ],
                [
                    52.037105,
                    0.643839
                ],
                [
                    52.048449,
                    0.669202
                ],
                [
                    52.058727,
                    0.700214
                ]
            ]
        }
    },
    "POIs": {
        "type": "Relationship",
        "object": [
            "urn:ngsi-ld:POI:b8873fb6-5aad-11e8-abb2-5b6a411669cd",
            "urn:ngsi-ld:POI:c1ac7a0c-5aad-11e8-86f2-97ddd7d561f4"
        ]
    }
}