Re: Multi-signature Verifiable Credentials

Hey @Manu Sporny <msporny@digitalbazaar.com>

What are the options you are considering for how to verify that a M/N proof
set contains the required number of signatures? How do you express the
condition for this?

What we are doing here is using the W3C Verifiable Condition
<https://github.com/w3c-ccg/verifiable-conditions>, a verification method
type. I am wondering if you have got a different approach?

Cheers,
Jack

On Mon, 3 Oct 2022 at 12:15, Jack Tanner <jack@tonomy.foundation> wrote:

> 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/>
>


-- 
_________________________________________

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/>

Received on Monday, 10 October 2022 08:38:09 UTC