Re: Multi-signature Verifiable Credentials

For the cases that we are looking at
* Using multiple proofs to perform set-based multi-signature. (we want to
be able to asynchronous sign the VC)
* Using multiple proofs to perform chain-based multi-signature.
* Using multiple proofs to perform multi-level/enveloped multi-signature.
* Using a single proof to perform set-based multi-signature. (sign a VC
with a number of keys at once)
* Using a single proof to perform chain-based multi-signature.
* Using a single proof to perform M of N threshold multi-signature. (we are
using W3C's Verifiable Condition to express this condition in the DID
Document)
* Using a single proof to perform privacy-preserving M of N  threshold
multi-signature.

Food for thought, the implementation we just finished with JWT's is a kind
of chain proof in the end to make it comply to the JWT standard - we nested
each JWS as the payload for the next JWS inside the JWT.

Proof sets for JSON-LD format is also a great approach.

Cheers,
Jack

On Sat, 1 Oct 2022 at 20:52, Manu Sporny <msporny@digitalbazaar.com> wrote:

> On Wed, Sep 28, 2022 at 4:08 AM Jack Tanner <jack@tonomy.foundation>
> wrote:
> > What should the proof look like?
>
> We're trying to lock this down over the next couple of weeks in the
> VCWG. The specific sections of the Data Integrity spec (with examples)
> are here:
>
>
> https://pr-preview.s3.amazonaws.com/w3c/vc-data-integrity/pull/59.html#proof-sets
>
> and here:
>
>
> https://pr-preview.s3.amazonaws.com/w3c/vc-data-integrity/pull/59.html#proof-chains
>
> > Which VC library would make the most sense for the initial
> implementation?
>
> Digital Bazaar's open source vc-js library will support proof sets and
> chains (as specified in the Data Integrity spec by the VCWG) in
> production. There is strong customer pull for proof sets. There is not
> strong customer pull for proof chains, but given that we have the
> opportunity to define a global standard for doing that AND because
> there are use cases like notarization that are important, we plan to
> add full support for that as well.
>
> Regarding the concept of multi-signature, I am a bit concerned that
> people are talking past each other as there are a number of categories
> there and it's possible that not everyone is talking about the same
> categories of multisig. There are at least these categories:
>
> * Using multiple proofs to perform set-based multi-signature.
> * Using multiple proofs to perform chain-based multi-signature.
> * Using multiple proofs to perform multi-level/enveloped multi-signature.
> * Using a single proof to perform set-based multi-signature.
> * Using a single proof to perform chain-based multi-signature.
> * Using a single proof to perform M of N threshold multi-signature.
> * Using a single proof to perform privacy-preserving M of N  threshold
> multi-signature.
>
> So, when you say "multi-signature" -- which one of these things are
> you talking about?
>
> -- 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/
>


-- 
_________________________________________

Jack Tanner
Founder and Architect | Tonomy Foundation
p: (+31) 6 2216 5433
w: tonomy.foundation e: jack@tonomy.foundation
<https://twitter.com/@theblockstalk>
<https://www.linkedin.com/in/jack-tanner/>