W3C home > Mailing lists > Public > public-credentials@w3.org > June 2017

Re: Negative VCs

From: Melvin Carvalho <melvincarvalho@gmail.com>
Date: Thu, 29 Jun 2017 07:05:07 +0200
Message-ID: <CAKaEYhKvURhFEB91vZPGqREFcdbxgMLByajyYYogrYiMy05axQ@mail.gmail.com>
To: Adam Lake <alake@digitalbazaar.com>
Cc: W3C Credentials Community Group <public-credentials@w3.org>
On 27 June 2017 at 17:30, Adam Lake <alake@digitalbazaar.com> wrote:

> On 6/26/2017 7:59 PM, Melvin Carvalho wrote:
> On 24 June 2017 at 00:38, David Chadwick <D.W.Chadwick@kent.ac.uk> wrote:
>> I think that most of us have been assuming that VCs are always positive
>> and confer some benefit on the subject. Common examples used by us have
>> been passport, credit card, club membership etc.
>> But what about negative VCs, such as a criminal record, 'points' on your
>> driving licence, or failure to pay a bill on time etc. Subjects are
>> going to be reluctant to present these to verifiers, especially if this
>> would remove any benefit that they were hoping to obtain from the
>> verifier's online service. In this case the VCs might be presented by
>> someone other than the subject of the VC, and by someone not wishing to
>> represent the subject of the VC.
>> For this reason I would support the following alternative wording in the
>> Terminology Playground
>> ROLE_B is typically the Subject of Claims. In some circumstances, where
>> the ROLE_B is not the Subject of the Claim, then ROLE_B must be able to
>> prove that they are 'authorised to provide the claim'. This is a
>> preferrable alternative to 'has the authority to represent the Subject
>> of the Claims', as it covers the latter case as well as a third party
>> providing negative VCs to a verifier.
> I think you've hit upon an incredibly interesting use case.
> One issue with centralized claims is that claims of a negative nature can
> be a point of failure when, say, the domain owner comes into conflict with
> the person who the claims about.
> For this reason businesses normally do not allow negative claims to be
> made to reduce that point of failure.
> However, there's another mode of the web where the claim can be
> independent of any central website or URL, just as, when the contents of a
> file is independent of that file itself.
> I think it's a really important use case and I have in our community heard
> many calls for such a system to emerge, but yet, we have not to date been
> able to solve such a use case effectively, at least in web 1.0 and web 2.0
> type offerings.
> I'm optimistic that web technologies can deliver claims of any kind which
> become the ownership of the author, rather than, the publisher.
> I honestly think the web is screaming out for this as one of the most
> important use cases yet to be addressed.
> In our reputation community we have explored this quite a bit, and the
> issue becomes one of sock puppets flooding the eco system with negative
> claims ... the question remains as to how to analyses a web of claims and
> get the signal from the noise.  From experience, what seems to be the case
> is that most actors are genuine, but a few try to game the system.  It
> seems something of an arms race.  I really look forward to innovation in
> this space, and one someone gets the ball rolling I think decentralized
> claims of this kind could be popular in a very viral way ...
> It seems to me that claims are verifiable free speech. We all have the
> freedom to say anything about anyone else, short of defamation. How we get
> the signal from the noise is each person defining their own web of trusted
> issuers through which level of trust per claim can be derived. Can't a
> flood of negative claims be disregarded as noise?

Flood attacks aka sybil attacks [1] need to be compensated for by the agent
that analyses the claims.

I agree with the free speech aspect.  Tho typically publishers of large
centralized sites can incur a liability of having to moderate comments.

The solution to this is to encourage authors to self publish on commodity
storage, and then the publisher becomes removed as the single point of

[1] https://en.wikipedia.org/wiki/Sybil_attack

> Adam
>> regards
>> David
> --
> Adam Lake
> Business Development Lead
> Digital Bazaar
Received on Thursday, 29 June 2017 05:05:40 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 11 July 2018 21:19:39 UTC