– DRAFT –
WoT Editors

Minutes review

<kaz> Feb-8

(Kaz walks through minutes)

Kaz: respec issues ...

McCool: can ignore for now

(minutes approved)

status of document checks

McCool: for discovery we still finish a big PR, will go over the whole document

terminology

McCool: mmc: there's a new terminology topic - we cannot use consumer, since discovery is optional in architecture
… we we are using d-client or d-consumer

Lagally: explorer?

McCool: already in use

Kaz: we should think about 2 levels of definitions: for device layer and software layer (i.e., real vs virtual)

McCool: some confusion on devices that have multiple things
… is node-red a consumer?
… need a word for entities that have a network interface and are not described with a TD

Lagally: why not use a TD for devices with a network interface?

McCool: different descriptions for outgoing connections. It is redundant from a security perspective. IETF works on MUDs.
… we could work on that in the next round.
… a consumer reads a TD

Kaz: we need to describe the two layers first, and then can discuss how to deal with "producer" vs "consumer"

McCool: we should define a device, which may have a network interaction.

Lagally: proposed definition: a device is a thing with a network interface

McCool: RDF can be used to describe entities, SSN describes features of interest.

Lagally: these are out of the scope we describe in WoT

McCool: thing is used in wide sense for entities
… we should not duplicate RDF

Ege: entities that do not have a TD, what do they have?
… script running in a computer or browser - we can have a description format, you can start with metadata, if you describe code we go into domain specific languages.
… if we have a TD with only metadata, who consumes it?
… I don't think we must have TDs for all entities

McCool: purpose of use cases is to narrow our scope
… need to be very precise, should not extend the scope

<kaz> oneM2M Definitions and Acronyms

<McCool> (to capture my point: suggest that Things are entities described by Thing Descriptions. Full stop.)

Lagally: we should not overcomplicate the discussion, not include further ontologies

Kaz: we should consider definition of entities, and we might want to look at oneM2M's definition and borrow some concepts from that :)

(detailed discussion about mqtt, endpoints, ...)

Kaz: we should distinguish 2 layers, physical and virtual. and those 2 layers should include at least device/application and Thing/Consumer.

McCool: agree before diving into detailed discussion about concrete definition, we should use a device and application

Lagally: can a TD only describe devices?

McCool: a SW service could also be a thing.
… the word device is useful, things are more broadly
… virtual thing / real things are used confusingly

Lagally: changing terminology will have a lot of ripple effects

McCool: we should avoid inconsistencies in terms

Kaz: we should start with a small set of definitions, may need to extend based on use cases
… in these discussions we can define what a thing can be. for example, how to handle a management Thing implemented as a software application for several physical devices.

McCool: two definitions are lacking: device, services

Lagally: can you please come up with 2 MRs for architecture?

<McCool> https://github.com/w3c/wot-architecture/issues/708

Ege: would still prefer to distinguish virtual things, digital twin is a service, shadow for a physical device

McCool: a shadow is a class of entities that simulate other things

Ege: non-device things?

Kaz: let's start with this model and extend it based on our concrete use cases before considering theoretical variations.

McCool: virtual thing is a kind of service that represents another thing
… let's also define digital twins and shadows

<McCool> https://github.com/w3c/wot-architecture/issues/708#issuecomment-1040186919

<McCool> https://github.com/w3c/wot-architecture/issues/709

<kaz> kaz: let's continue the discussion during the Architecture call

<kaz> [adjourned]