W3C

- DRAFT -

WoT Architecture

24 Sep 2020

Agenda

Attendees

Present
Kaz_Ashimura, Michael_Lagally, Michael_McCool, Ryuichi_Matsukura, Tomoaki_Mizushima, Michael_Koster, Zoltan_Kis
Regrets
Chair
Lagally
Scribe
ryuichi, kaz

Contents


<kaz> scribenick: ryuichi

Agenda

Lagally: logistics
... Architecture 1.1 contributions and new requirements
... Issues
... Profiles
... any more agenda for today?
... none

Prev minutes

<kaz> Sep-17

Lagally: any objection?
... approved.

Pull requests

<kaz> scribenick: kaz

wot-architecture PRs

PR 539

Lagally: let's defer this one since we don't have Zoltan now

PR 540

Lagally: not ready

McCool: we had discussion on Thing Model during the TD call yesterday
... use cases for Thing Model needed
... to see Digital Twin and Developer support
... for digital twin, protocols don't matter
... but for developer support protocols matter and would see security information as well
... would see whether protocols and security information to be mandated or not

Lagally: also would see the big data use case

big data use case MD

McCool: for developer support, you need protocols and security information

Koster: when you have things which are not online
... not sure if the developer support use case is so different from digital twin
... to me interaction has to be there
... could be at different stages

McCool: would avoid duplicate names

Koster: what we call workflow

McCool: fill in the details on the interaction

Koster: helpful to show what is considered by IoT Schema, etc.

McCool: we should have some general statement
... as for developer time, there are two kinds
... those using scripting API
... vs doing all myself

Lagally: would be nice to use the queue :)
... we want to have Thing Model
... but need to clearly state that
... precise definition
... when we have a formal relation type
... need structured data type

Kaz: would suggest we start with the use cases themselves
... and elaborate the requirements based on them

McCool: agree
... also we should think about minimum requirements as well
... some use cases might be more desirable

Lagally: we already have a requirements description on "thing template"

thing template requirements

Lagally: should be renamed (to "thing-models.md")

McCool: maybe we can add "variants"
... also minimum requirements?

Koster: please continue

Lagally: requirements section includes...

Koster: if you look at the overlap with oneDM and IoT Schema...
... think Sebastian would like to have a mechanism so that TD can do what oneDM can do
... some of the use cases have schema and some don't
... it's an orthogonal thing
... if I have a thermostat, I have two levels
... the last one is TD which has the address and device type
... do we want to make TD have the whole lifecycle capability, etc., like oneDM has?
... basically it's part of the discussion

Lagally: why don't we start with what we currently have?
... based on our own use cases

McCool: we should clarify the Thing Model
... interaction and schema first
... and could add modularity, etc., later on

<McCool> ... once we have modularity, we can perhaps add a "Thing Capability" which is like a Thing Model, but perhaps with just affordances (and no data schemas for instance)

Kaz: maybe we might want to have an additional section of "what we want" right before the "requirements" section to clarify our background on the need for requirements
... for example, Michael McCool wants to think about security portion
... and Michael Koster is interested in the compatibility with oneDM, IoT Schema, etc.

McCool: yeah, that would make sense

Lagally: (adds a subsection of "what do we want for different use cases?")
... (and adds subsections of "Digital Twin" and "IoT Orchestration")

(some more discussion on "what we want" from various viewpoints)

Lagally: (captures the summary)

McCool: would compare "Digital Twin Modeling" and "IoT Orchestration Modeling"

Lagally: would like to see "Big Data" use case as well here

Kaz: we might want to have some concrete scenario for each use case
... those three use cases are horizontal ones and could be applied to various vertical use cases
... but we could identify some typical scenario like gas plant which mentioned in the use case section of the v1 Architecture spec

McCool: would see the description on the abstract level now
... could revisit concrete cases later
... minimum quirements for common elements are interactions and data schemas

Lagally: inheritance of multiple classes would be too complicated

McCool: as a starting point, could focus on single inheritance

Lagally: (adds constraints)
... Thing Model constraints must appear in the Thing Description with possible additional details
... wondering if we could have some description on possible alignment between oneDM and Thing Model

Koster: that would make sense

Lagally: would suggest we allocate a slot for that, e.g., next week

Koster: ok

McCool: maybe semantically annotated TD would be useful?
... btw, next week will be PlugFest

Koster: yeah
... will busy as well
... related to the use case on generating TD from SDF
... workflow you could take things

Lagally: (adds an agenda item on the discussion to the Architecture call agenda)

Koster: when to do that?

Lagally: Oct 1?
... Thing Models and OneDM

McCool: would include SDF explicitly

Lagally: yeah, SDF is a separate IETF WG now
... more technical discussion there

McCool: also requirements and enhanced use cases for Thing Models
... would have Sebastian as well

Lagally: (puts Sebastian's name there with a note of "TBD")

Kaz: thanks a lot for the discussion
... and I think it would be even nicer to have some more supplementary description on why we want this mechanism
... based on today's discussion
... e.g., need a flexible mechanism to automatically generate TDs for these horizontal use cases

Lagally: (adds supplementary description on that)

McCool: open issues on modularity, etc.

Lagally: (adds that to "Open issues" section)

<mlagally> updated Thing Models Requirements

Issue 538

Issue 538

Lagally: who could generate an updated diagram?

McCool: maybe Toumura-san?

Lagally: (adds a comment to Issue 538)
... could you ask Toumura-san about this?

McCool: will do

Issue 534

Issue 534

Lagally: who could work on this?

McCool: can work on that

Issue 530

Issue 530

Lagally: McCool, can you work on this?

McCool: ok

Issue 527

Issue 527

Lagally: somebody to generate requirements for time stamps/time series
... related to media use cases?

Kaz: can ping the MEIG guys about the pre-meeting on Oct 1
... also the joint discussion on Oct 7
... could ask NHK guys as well

Lagally: ok. let's defer this then

Issue 526

Issue 526

Lagally: requirements on accuracy

Koster: can look into this

Lagally: if we could have a starting point, would be able to accelerate the discussion

Issue 523

Issue 526

Lagally: not ready today

PR 539

PR 539

(GitHub Preview doesn't show the diagram, Statically requires account. so Kaz shows the index.html and the diagram which have been locally cloned)

Zoltan: maybe need to update the transitions
... it's complex

Lagally: would illustrate what happen for lookup, etc.

McCool: this is device lifecycle
... would see how to upgrade the system too
... resource needed for access control

Zoltan: commissioning for WoT?

Lagally: McCool, could you add a comment to PR 539?

Zoltan: please leave comments

Lagally: need some label for "resume" etc., to come back to the "Operational" state from "Maintenance"?

Zoltan: wondering about what would be the good name
... I'm open for suggestions

Lagally: ok
... this is work in progress

Zoltan: what else do you need?

McCool: why don't we have a quick review round?
... would prefer merge this and review the changes
... having an acronym of "TD" is confusing

Lagally: we're out of time
... why don't we keep this open, and continue the discussion next week?

AOB

McCool: two editorial PRs for small changes

wot-architecture PR 541

wot-usecases PR 53

[adjourned]

Summary of Action Items

Summary of Resolutions

[End of minutes]

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$Date: 2020/09/29 15:44:13 $