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Re: Rendering Verifiable Credentials @ RWoT11

From: Stephen Curran <swcurran@cloudcompass.ca>
Date: Mon, 18 Jul 2022 09:39:36 -0700
Message-ID: <CAFLTOV4TR21qdq-U7Lo27yfH16nJjN4sKyuKLxjMLqMm_uj=dA@mail.gmail.com>
To: Kerri Lemoie <kerri@openworksgrp.com>
Cc: Manu Sporny <msporny@digitalbazaar.com>, W3C Credentials CG <public-credentials@w3.org>, public-vc-edu@w3.org
Hi Manu -- sounds like we're all getting to the UX issue.  Shows the
progress being made in the community!

In addition to the rendering for appearance, we're very much interested in
multilingual presentation of credentials, including being able to provide
informational data about the attributes. Ideally, this information is
verifiably linked to a known (dare we say "trusted") party (e.g. the schema
publisher or credential issuer), and used by holder software (e.g. a
wallet) to render the credential, and perhaps also be verifiers for
displaying attributes included in a presentation.

In the Aries/AnonCreds world, we're applying the work being done in the
"Overlay Capture Architecture"(1, 2) (OCA) open specification. OCA provides
a mechanism for defining layers of information about any data model. Its
roots are in Pharma industry interop, but applies very nicely to
credentials, and is also being used in the Chained Credentials (ACDC) /
KERI work.

Basically, the publisher of the schema or the issuer of a credential (or
other "trusted" party) defines an "OCA Bundle" -- a base layer consisting
mainly of the names of the data attributes in the credential, and then a
set of overlays, each of which adds a dimension of semantic information.
We're using these layers:

   - Multilingual naming of the credential type and issuer (one layer per
   - Multilingual labels per attribute
   - Multilingual help information per attribute
   - Image and the layout of multilingual labels and data over the image
   - Multilingual Code/Value (e.g. enumerated code values like Vaccine
   - Flagging of data elements that are PII (enabling UX opportunities for
   holder software when creating presentations to send to verifiers)
   - Data format
   - Data encoding
   - Suppression of attributes in the credential but deliberately not
   populated by the issuer (e.g. nulls)

From a practical perspective, all but the image/data layout can be provided
in source form using a structured spreadsheet (with a tab per language)
that is converted to the OCA Bundle (basically, a zip file of
cryptographically linked JSON files -- one per overlay). The use of a
spreadsheet simplifies the business process of collecting multilingual data
elements. The OCA Bundle is then published by an appropriate participant.
With AnonCreds, we're having the schema publisher or credential issuer
publish a resolvable, signed instance of the OCA Bundle that the holder or
verifier can retrieve on receiving a credential or presentation. Tooling is
available for all the steps, and it's a relatively light lift to add the
capability to Aries to provide required (multilingual!!!!) capabilities,
and options to render beautiful credentials (multilingual labels/data over

A link to enable resolving the OCA Bundle could be put into the credential
itself as an attribute, although for AnonCreds, we're going to be use the
related identifiers (the schema and the issuer credential type) as the link
to finding trusted, signed OCA Bundles.

I'm not likely not going to make it to RWoT in Den Hague, but would be glad
to discuss this with anyone interested in this approach to the challenge.

[image: image.png]

(1) Overlays Capture Architecture -- https://oca.colossi.network/
(2) OCA Specification: https://oca.colossi.network/v1.0.0.html

On Mon, Jul 18, 2022 at 7:14 AM Kerri Lemoie <kerri@openworksgrp.com> wrote:

> Hi Manu,
> We have an open issue for this in vc-edu. I added the archive link to your
> email to this issue: https://github.com/w3c-ccg/vc-ed/issues/16
> I’m also CCing the vc-edu mailing list and will mention in today’s call.
> This is something the task force would like to stay in the loop on. I can’t
> offer direct assistance right now but can confirm that it has come up
> frequently with wallet providers and issuers of Open Badges.
> Thanks!
> K.
> On Jul 17, 2022, at 5:21 PM, Manu Sporny <msporny@digitalbazaar.com>
> wrote:
> Hey W3C Credentials CG, VCWG, and APAWG (bcc'd),
> The Verifiable Credentials ecosystem is experiencing increasing adoption
> in a
> variety of markets such as education, supply chain, retail, banking and
> finance, workforce training, and corporate and government identification
> cards. Each of these markets have issued credentials for hundreds of years
> and
> have (justifiably) pre-conceived notions and preferences around what their
> credentials should look like.
> Similarly, it is important to understand that visually representing a
> Verifiable Credential in certain ways could accidentally exclude those with
> accessibility needs. We need to consider people with visual needs such as
> larger font sizes, or the need to use colors that are easily discernable
> (e.g., red-green color blindness). We also need to design for those that
> cannot see, how do they navigate digital wallets and use Verifiable
> Credentials?
> This draft Rebooting the Web of Trust 11 paper explores ways in which the
> Verifiable Credentials data model could be extended to support visual,
> audio,
> and physical renderings for Verifiable Credentials.
> https://github.com/WebOfTrustInfo/rwot11-the-hague/blob/master/advance-readings/rendering-verifiable-credentials.md
> So, three things:
> 1. This is a reminder that RWoT11 Early Bird papers are
>   due in two days (July 19th):
> https://www.eventbrite.com/e/rebooting-the-web-of-trust-xi-2022-the-hague-tickets-347605426187
> 2. We desperately need help from the Accessibility
>   community if we have any chance of getting this even
>   remotely right.
> 3. Is anyone interested in collaborating on this paper, or
>   providing other ways you've approached rendering
>   Verifiable Credentials?
> Thoughts?
> -- manu
> --
> Manu Sporny - https://www.linkedin.com/in/manusporny/
> Founder/CEO - Digital Bazaar, Inc.
> News: Digital Bazaar Announces New Case Studies (2021)
> https://www.digitalbazaar.com/


Stephen Curran
Principal, Cloud Compass Computing, Inc. (C3I)
Chair - Sovrin Foundation (sovrin.org)

*Schedule a Meeting: **https://calendly.com/swcurran

(image/png attachment: image.png)

Received on Monday, 18 July 2022 17:09:49 UTC

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