Device kinds and device types

related to saref-portal#101 (closed)

It is still unclear when one wants to model a generic kind of device (aka, model, category, class, ...), whether they should model it as an instance of saref:Device, or a subclass of saref:Device.

It would help a lot to be able to identify kinds of devices generically, the same way we do with property kinds. One advantage would be that we could reuse existing code lists, vocabularies, and taxonomies. Identifiers could be for example:

• Uniclass (ex: Pr_75_50_76_88 Toxic and combustible gas detectors)
• Harmonized Tariff Schedule (HTS) Code (ex: HTS Code: 9025.80.1000 for Electrical Hydrometers And Similar Floating Instruments, Thermometers, Pyrometers, Hygrometers And Psychrometers)
• eClass
• Global Trade Item Numbers (GTINs) , Universal Product Codes (UPCs) , European Article Number (EAN), etc.
  • see mapping to URNs: https://www.gs1.org/edi-xml/technical-user-guide/5_GS1_namespaces
  • see RFC 5134 "A Uniform Resource Name Namespace for the EPCglobal Electronic Product Code (EPC) and Related Standards"
  • see GS1 Digital Link https://www.gs1.org/standards/gs1-digital-link
  • ex GTIN + Batch/lot (LGTIN) EPC URI urn:epc:class:lgtin:061414.0100000.987654321GFEDCBA
  • ex Serialized GTIN (SGTIN) EPC Scheme urn:epc:id:sgtin:061414.0100000.ABCDE12345

Another advantage is that it would encourage manufacturers and vendors to define permanent URIs for their devices, and to expose structured data at the page that describes a device in a catalogue. Some examples of product IDs from manufacturer and vendor catalogues:

• XMLD010B1S11 Pressure switch XMLD 10 bar - 2 stages fixed scale - 2 C/O https://tesensors.com/global/en/product/reference/XMLD010B1S11
• BMP282 high-precision barometric pressure sensor https://www.bosch-sensortec.com/products/environmental-sensors/pressure-sensors/bmp280/
• Adafruit 5187 (STEMMA QT SCD-40 CO2 Humidity and Temperature sensor) on Digikey https://www.digikey.fr/fr/products/detail/adafruit-industries-llc/5187/15194668
• Adafruit 5187 (STEMMA QT SCD-40 CO2 Humidity and Temperature sensor) on mouser.fr https://www.mouser.fr/ProductDetail/Adafruit/5187

My proposal to disambiguate the concept while maintaining backward compatibility with previous usages would be to split saref:Device in two classes:

saref:DeviceOfInterest

An instance of saref:DeviceOfInterest represents one specific real world device.

saref:DeviceKind

The class saref:DeviceKind allow to describe models of devices, with common properties having the same value, common states being the same, common functions, and common services. It describes a datasheet, vendor specification, or normative specification, of a device (in the sense of a prototypical description).

EXAMPLE: system with European Union energy label A++ , Energy Star labeled appliance, BMP282, DHT22, Adafruit 5187, ...

NOTE: Concepts from existing code lists, vocabularies, and taxonomies, may be used as instances of saref:DeviceKind.