10 Jul 2020



Kaz_Ashimura, Sebastian_Kaebisch, Ege_Korkan, Michael_Koster, Marcus_Schmidt, Cristiano_Aguzzi, Tomoaki_Mizushima, Christian_Glomb
Ege, kaz


<kaz> scribenick: Ege

Marcus Schmidt as an invited guest for today

<kaz> W3C Patent Policy

Sebastian: (showing the agenda)
... anything else for the agenda?


Previous minutes

Sebastian: (review of the minutes)

<kaz> June-12

<inserted> scribenick: kaz

jun-12 minutes approved

vF2F minutes

Kaz: what about the vF2F minutes esp. the TD part?

Sebastian: would postpone to the next call or the main call because we're full today

CoAP RDF vocabulary

Issue 97 - wot-binding-templates

Sebastian: work with IETF via liaison
... Klaus will lead the discussion

<inserted> scribenick: Ege

Sebastian: The meetings about the RDF Vocabulary of CoAP has been discussed
... the outcomes are documented in issue 97

New TD slot

Sebastian: we need to pick a new slot
... for the TD call

<kaz> doodle

Sebastian: (shows the results)
... we want to pick wednesday 4-6 pm(CEST)
... it makes sense to have 2 hours
... is it ok for all?
... it is an improvement for the US east coast
... any objections for the new time slots?

<kaz> kaz: to be fair, we could start with this proposal and move the slot in 6 months if needed :)

<kaz> proposed slot on Wed

RESOLUTION: we will move the TD meeting to a new time slot. The new time slot is Wednesday 4:00pm-6:00pm CEST.

Sebastian: I am not there the whole next week but asked taki to chair the meeting

Kaz: next week meeting means wednesday, July 15 right?

Sebastian: yes, we start next week with the new slot

ROS Binding

<kaz> @@@ slides tbd

Marcus: so I start
... here are some robots, that have different capabilities
... ros allows to bind different protocols as a framework
... and to share code over different robotics applications
... there are master, talker and listener nodes
... similar to MQTT but the nodes can talk with each other without a middleman

Sebastian: what is the robot in this case

Marcus: nodes can be Thing or Consumer
... so how can ROS be mapped to WoT
... invokeaction can be mapped to Publisher, subscribeevent and observeproperty can be mapped to Subscriber in ROS
... so in slide 11, an example TD with ROS can be seen
... we see a URI scheme proposal, vocabulary proposal

Cristiano: what about defining contentType vocabulary like ros:contentType

Marcus: this is a nice input, I didn't think of this yet
... I have a discussion slide on this. also there is a GH issue as well.

<kaz> TD issue 912 on DataSchema and ContentType

Marcus: so adding ROS would be a nice addition to WoT since it is widespread

<Zakim> kaz, you wanted to ask if we can get the slides later and to ask about time synchronization among multiple "parts" and accuracy of the time

Kaz: Could you publish the slides on W3C WoT repository

<kaz> kaz: also it would be good to continue collaboration about time synchronization, time accuracy, geolocation, position of parts, etc., too

Cristiano: Did you work on a binding?

Marcus: so not really, I have written the TD and manually consumed and wrote the requests. I can work on it later

Sebastian: what implementation did you use

Marcus: Python with rospy

Sebastian: Could you make it public?

Marcus: sure

Sebastian: thank you for the presentation, it is nice to see that WoT can be used for ROS and be used to communicate with robots

Issue 923

<sebastian> https://github.com/w3c/wot-thing-description/issues/923

<inserted> scribenick: kaz

Ege: Philips Hue security scheme


"href": "{{mytoken}}/lights/1"


Ege: opened another issue since this is not official token handling

Issue 922 on apikey


"href": "http://example.org/thing/property/temp{?unit,api_key}"


Sebastian: related to each other
... also need input from the Security TF
... is this notation related to the TD Template idea?
... or another mechanism?

Ege: IP address would be templated
... Koster, any idea?

Koster: was using node-red for the security part

Ege: kind of a proxy

Koster: yes
... seems like HUE has some common security material

Ege: yeah, people who have physical access can get apikey
... from my viewpoint, {{mytken}} is the only solution
... using '{{' and '}}' based on the template mechanism
... Twitter also does similar thing

Sebastian: we need security experts for this topic
... McCool should be able to join the new slot on Wednesday
... assigns issue 923 to McCool

<scribe> scribenick: Ege

Issue 921

Issue 921

Sebastian: Ben Francis provided the differences between W3C WoT and Mozilla IoT
... issue nb. 921
... also he mentioned the WebThing community group
... We have remaining discussion about defining TDT
... there is discussion on the architecture
... issue 454 on architecture

Cristiano: if we do this "TD is an instance of one or more TDT" we need to define how it happens
... like from a programming language

<inserted> scribenick: kaz

Kaz: as a starting point, this is good, but we need to clearly define "the same capability" at some point

<inserted> scribenick: Ege

Sebastian: why TDTs are needed
... mass production, digital twins, simulation, combining different models

Ege: how would combining work?

Sebastian: it would happen in the development but you of course need to implement the backend

Koster: we need to be able to validate TDTs

Sebastian: analogies for TDT can be seen in programming languages

Cristiano: do you mean that TDs are not instances of TDTs?

Sebastian: sort of, so when you instantiate the variable of a class, what you get is still not a TD
... (shows extend mechanism)

Cristiano: TDs could implement multiple inheritance, which is not possible in many programming languages

Placeholder mechanism

<sebastian> https://github.com/w3c/wot-thing-description/issues/897

Sebastian: we need a way to use variables strings in TDs by defining where the values could be used, proposals show {{ }}

<sebastian> https://github.com/w3c/wot-thing-description/issues/898

Sebastian: we have a shacl shape that can be used for templating approach

<sebastian> https://github.com/w3c/wot-thing-description/issues/903

Koster: so you can go to examples in the SDF plaayground and these are mostly from OCF and similar other ones

Sebastian: So the next steps would be to formalize TDTs
... and then SHACL to extend TDTs

Cristiano: I can try

Sebastian: we can ask victor as well


Summary of Action Items

Summary of Resolutions

  1. we will move the TD meeting to a new time slot. The new time slot is Wednesday 4:00pm-6:00pm CEST.
[End of minutes]

Minutes manually created (not a transcript), formatted by David Booth's scribe.perl version (CVS log)
$Date: 2020/07/13 08:01:04 $