RE: 4-Corner Credential Interoperability Model

80% of it.  I’ll have a full demo at IIW.  There’s actually a small flaw in the “version 0.65” diagram in my previous post because it is difficult to actually transform and re-sign the credential on the right side as well as re-auth-encrypt the DIDComm credential exchange message with the re-signed credential.  “Necessity being the mother of invention” led to the creation of the concept of DIDComm Agent logical composition: If you have N DIDComm Agents connected serially from a message transfer perspective, this scenario can be recoded as a single physical DIDComm Agent with N inbound service endpoints.  Using DIDComm Agent logical composition, the equivalent working version 0.66 solution looks like this…

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From: Wayne Chang wayne@spruceid.com<mailto:wayne@spruceid.com>
Sent: Saturday, February 4, 2023 10:08 PM
To: Michael Herman (Trusted Digital Web) <mwherman@parallelspace.net>
Cc: Christopher Allen <ChristopherA@lifewithalacrity.com>; G. Ken Holman (g.ken.holman@gmail.com) <g.ken.holman@gmail.com>; Steve Capell <steve.capell@gmail.com>; public-credentials (public-credentials@w3.org) <public-credentials@w3.org>; sam@prosapien.com
Subject: Re: 4-Corner Credential Interoperability Model

Cool, do you have any code to run this?

On Sat, Feb 4, 2023 at 19:38 Michael Herman (Trusted Digital Web) <mwherman@parallelspace.net<mailto:mwherman@parallelspace.net>> wrote:

If you use some DIDComm imagination, it's easy to see how the 4-Corner Credential Interoperability Model is highly complementary to supporting a layered VC model ...here's a glimpse.  "More news at 11..."



[cid:image001.jpg@01D938E8.00D2E690]



-----Original Message-----
From: Steve Capell <steve.capell@gmail.com<mailto:steve.capell@gmail.com>>
Sent: Saturday, February 4, 2023 4:24 PM
To: Michael Herman (Trusted Digital Web) <mwherman@parallelspace.net<mailto:mwherman@parallelspace.net>>
Cc: public-credentials (public-credentials@w3.org<mailto:public-credentials@w3.org>) <public-credentials@w3.org<mailto:public-credentials@w3.org>>; G. Ken Holman (g.ken.holman@gmail.com<mailto:g.ken.holman@gmail.com>) <g.ken.holman@gmail.com<mailto:g.ken.holman@gmail.com>>; Christopher Allen <ChristopherA@lifewithalacrity.com<mailto:ChristopherA@lifewithalacrity.com>>; sam@prosapien.com<mailto:sam@prosapien.com>
Subject: Re: 4-Corner Credential Interoperability Model



I think the 4-corner model is the opposite of the VC model.  It’s a EDI message routing framework that delegates the problem of trust (ie trader identity verification) to EDI hubs.  Hubs perform a “service” to their authenticated subscribers to map messages to the format they need - so forget about document integrity (how do you maintain a signature when the document is transformed at two hubs?).  There’s nothing verifiable about the message that eventually lands with the receiver (through 2 hubs).  Instead the parties have to trust that the hubs have properly identified their clients and have not lost anything in translation



It’s also expensive (every message attracts  two clip-fees).  I’ve never seen this model achieve any significant uptake except in cases where it is mandated by a national regulator



Kind regards



Steven Capell

Mob: 0410 437854



> On 4 Feb 2023, at 10:49 pm, Michael Herman (Trusted Digital Web) <mwherman@parallelspace.net<mailto:mwherman@parallelspace.net>> wrote:

>

> A colleague of mine, Ken Holman from Ottawa, recently produced a conference paper on the topic of the 4-Corner Credential Interoperability Model. It's originated in the OASIS Universal Business Language (OASIS-UBL) community where they were experiencing problems with spec compliance, interoperability, and low/slow technology adoption rates. UBL is a set of 90+ schemas defined for the most commonly used business documents used in commerce today.

>

> The 4-Corner Credential Interoperability Model is a simple, efficient, low-cost approach to enable different communities or trading associations to easily interoperate through the exchange of different types of credentials. For example, this would be a stepping stone for enabling a layered approach to how verifiable credentials are defined, used, and exchanged - an opportunity to move away from a "one-size fits all" niche VCDM specification to a layered model that addresses the dual needs of:

> a) the layering of simple, more generic models through to more complex

> niche credential specifications,  as well as

> b) an interoperability model that is simple, secure, efficient, and low-cost.

>

> Live Presentation: Case study of a semantic library underpinning the

> 4-corner model for document exchange 2022-11-08

>

> https://www.linkedin.com/posts/gkholman_ken-holman-case-study-of-a-sem


> antic-library-activity-7001714323223977985-IKbA

>

> Case study of a semantic library underpinning the four-corner model

> for document exchange

> https://doi.org/10.1075/da.2022.holman.four-corner-model


> Proceedings of Declarative Amsterdam 2022 (7 and 8 November 2022)

> Available under the CC BY 4.0 license.

>

>

>

> Best regards,

>

> Michael Herman

>

> Web 7.0

>

>

> <winmail.dat>