W3C

– DRAFT –
Automotive Working Group Teleconference

09 November 2021

Attendees

Present
Adnan, Carine, Erik, Gunnar, Isaac, MagnusG, Peter, Ted, Ulf
Regrets
Isaac
Chair
Peter, Ted
Scribe
ted

Meeting minutes

MQTT PR continued

Ulf: the major change is scrapping VIN for an arbitrary identifier
… I changed the wording to vehicle identity

Ted suggests clarification that this is not necessarily VIN

Gunnar: there are cases where broker might be in-vehicle

Erik/Ulf think it is covered

Erik: diagram image rendering is different for changed terms
… font or clarity

Ulf: I did it in a pixel editor on the original diagram

[discussion on image edit and format]

https://github.com/w3c/automotive/pull/427

Ted to propose wording for his suggestion

Issues

https://github.com/w3c/automotive/issues

https://github.com/w3c/automotive/issues/382

Ulf: I proposed we have Signal Access Claim in the token as alternative to Role Based Access Control
… nothing more is said about how the topic is obtained, it is out of scope and left to the implementer
… this meets what has been asked for from Bosch side, less complex authentication
… Isaac came up with an idea to do essentially the same thing but more in-line with the existing mechanism
… I find it a fully valid proposal but found one issue. the main reason for introducing this new "flow" was to make an implementation that excludes policy document but also the authorization server
… this proposal goes beyond that. Sebastian took a look and prefers the earlier proposal that has the lower complexity
… Isaac commented further about HTTP API security

Article Isaac shared on Slack

https://github.com/w3c/automotive/issues/430

Ulf: how do we handle discoverability?

Ted: we discussed before (and punted iirc?) leveraging something like uPNP for discovey or similar to VID or SAC token, outside the scope and handled by configuration

Carine: we could settle on port numbers

Magnus: this is deployment specific and could be out of scope

Carine: it could be part of a manifest file, a way to discover in all vehicles. is it using default port or something else
… we could narrow the scope. it would be better to specify what is deployed

Erik: is it clear there would only be one access grant server or could there be multiple?

Ulf: there is one within an ecosystem

Erik: another issue is information about what VSS version is being used. if you just know the name of the VISS server, you can get the additional information from it
… VISS server can provide that

Ulf: I don't think we should specify how a client obtains address for the VISS server, it is up to the OEM

https://www.w3.org/TR/2018/CR-vehicle-information-service-20180213/ VISSv1

wss://wwwivi

Ted: when we discussed for v1, it was a problem for other W3C groups as well. the static local network hostname was not preferred and I can look to see if the cross group discussion reached a conclusion

Ulf: let's leave this open then

https://github.com/w3c/automotive/issues/429

Ulf: access token server could sign with its private key and provision clients with public key
… if you don't have a VIN the token could possibly go to any vehicle as valid

Ulf: we can have it as optional
… I'll generate a PR for Erik's idea, having it in the token

Erik: sounds good to me

https://github.com/w3c/automotive/issues/425

Ulf: VIN parameter should be optional here too

[Isaac joins]

[return to issue 382, Ulf recaps conversation]

Ulf: anyone who implements an access control model will ensure they meet their security criteria

Erik: would we remove or deprecate any of the flows?

Ulf: no, which is used up to implementer and they could use both
… ideal is to have interoperability from client perspective

Isaac: my understanding was to try to find a middle ground and align with what people are likely to do
… if people want to skip access grant server, ok we can simplify the flows
… my proposal was a small simplification to the proposed flow to align better with the earlier solution

Ulf: understand and appreciate that
… Bosch wanted something simpler and asked Sebastian to describe better what they want
… my understanding is that it isn't rigidly defined but want it flexible
… token is then the lowest common denominator

Isaac: how the token is protected can be with HMAC

Ulf: I can bring forward a PR and have a final discussion on the details

Minutes manually created (not a transcript), formatted by scribe.perl version 159 (Fri Nov 5 17:37:14 2021 UTC).

Diagnostics

Succeeded: s/when application use case is in-vehicle is it needed?/there are cases where broker might be in-vehicle/

Succeeded: s/is a bit off/is different for changed terms/

Maybe present: Magnus