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A resource model that links basic concepts of a ROA to the concepts “service” and “interface” is defined in the Information Viewpoint in section 7.6.3.
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A SANY RESTful Web Service platform is defined in the Technology Viewpoint in section 9.2.3.
6.5.2 URN Namespace for SANY Resources
Interoperability in sensor network applications depends to a very large extent on a mutual agreement about identifiers of resource types and their underlying semantics. The SensorSA
distinguishes between the identifier itself and its semantics:
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The identifier scheme shall be based on Uniform Resource Names URN to unambiguously reference location-independent identifiers.
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The semantics of an identified resource are provided when URNs are resolved. As a minimum, the semantics shall be provided in the form of free text descriptions.
Optionally, the semantic description may be enriched and made more concrete by references to taxonomies or ontological concepts.
Basically, resources used in the SensorSA are identified in the “Uniform Resource Name URN Namespace for the Open Geospatial Consortium OGC” RFC 5165 which is
structured as follows:
urn:ogc:{OGCresource}:{ResourceSpecificString}
For resources that are defined in the scope of the SANY Sensor Model see section 5 or for the purpose of SANY applications, the sub-
tree of the OGC resource type “def” as defined by the URN resolver of the OGC Naming Authority http:www.opengeospatial.orgogcna
shall be used. The resulting naming scheme for SANY URNs is:
urn:ogc:def:objectType:authority:[version]:code
with the following definitions:
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objectType denotes concepts in the form of a controlled list currently defined in table 3 of OGC 06-023r1. In particular, the SensorSA shall use object types that are
related to the Sensor Model such as
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“phenomenon” observable property definition or
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“uom” unit of measure definition.
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In addition, the term eventType shall be used to denote events e.g. sensor available, or threshold exceeded. The event URN usually comes with a
related phenomenon URN. For instance, the URN urn:ogc:def:eventType: SANY:2009.03:occurrence is related to urn:ogc:def:phenomenon:SANY:
2009.03:earthquake.
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authority denotes organisations e.g. standardisation organisations such as ISO or OGC, but also projects such as SANY that define the resource identifiers. It is a
controlled list defined as follows:
authority := EDCS | EPSG | OGC | SI | UCUM | SANY Note: This list is an extension of table 1 of OGC 06-023r1 by adding the authority
“SANY”.
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version denotes the version of the resource identifier definition as defined by the authority.
Note 1: For the authority OGC the version is optional as stated in section 7.2 of
OGC 06-023r1: ―The ―version‖ part of these URNs can be omitted when the
referenced definition does not have a version, and the referenced definition is not specific to an authority
version. When included, the ―version‖ shall be recorded in the format specified by the authority. The version format is sometimes ―N.N.N‖ or ―N.N‖,
where each ―N‖ stands for an integer. If no other version identification is provided by the authority, a year or other date can be used. No v or other version prefix shall be
included.‖ Note 2:
For the authority SANY the version is mandatory when defining a URN and it shall be provided in the format “N.N”, where each “N” stands for an integer.
When referring to a URN and the version number is missing, the resource that is associated with the highest version number shall be taken by default.
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code denotes a human-readable name that identifies the resource. Note: URN namespaces for OGC and for SANY must not be confused with XML
namespaces used in schema documents of the eXtensible Markup Language XML. According to the W3C Recommendation “Namespaces in XML 1.0”
http:www.w3.orgTRxml-names , “XML namespaces provide a simple method for
qualifying element and attribute names used in XML documents by associating them with namespaces identified by URI references”.
6.5.3 Naming principles
