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VC API Task Force

Transcript for 2022-07-26

Our Robot Overlords are scribing.
Joe Andrieu: Recording is on.
Manu Sporny: All right welcome everyone to the VC API work item call this is July 26th 2020 to our agenda is here in.
Manu Sporny: Chat channel on the agenda today just to review introductions reintroductions relevant Community updates Marcus I'm going to ask you about the rch working group and in some stuff there so that's coming up we are going to continue reviewing the VC API use cases and go through some of that stuff and then on to the question around in the exchanger serviced in presentation exchanges.
Manu Sporny: The did Authentication Protocol did all the protocol that may come into play when we were talking about the GFF plugfest and supporting that and then other issues as time permits are there any updates or changes to the agenda that we should go over.

Topic: Relevant Community Updates

Manu Sporny: You know changes I'll note that we all know each other on the calls I'm going to skip introductions and reintroductions and go right into relevant Community updates let's start off with the rch working group to get that link.
<manu_sporny> RCH WG:
Manu Sporny: Is so the rch working group has been created Marcus would you like to give us kind of an introduction to the group and when the works kicking off timeline would be good.
Markus Sabadello: Yes sir that working group exists now and people can join we expect that the work will start after the summer maybe in in September there will be a kickoff meeting it tpack the joint session also way to verify the credentials to working group because of the relationship between the groups the objective of this one rdf data set comical ization and hash.
Markus Sabadello: So known as rich.
Markus Sabadello: Will be to Define specifications for canonicalizing and hashing rdf data sets as the name suggests and this is important for one of the ways how verifiable credentials can be secured with data Integrity this is a piece that's strictly speaking missing right in the in the VC stack how exactly linked data proofs previously also.
Markus Sabadello: Let's link fatal signature.
Markus Sabadello: How they are created Hardy.
Markus Sabadello: If Theta is like I'm Nan canonicalized and hashed before it can be signed and there may also be broader used for this work Beyond verify your credentials in linked data spaces and some some other communities there's there's interest so it is a very narrowly scoped working group to just Define hopefully small missing piece in the stack but.
Markus Sabadello: Still alive interesting 21 who's building things with its and Reese's.
Manu Sporny: Awesome thank you for that Marcus any questions about the rich working group before I move on.
<manu_sporny> Publication request for Data Integrity CGFRs
Manu Sporny: The other item is this publication let me clean this publication request for some data Integrity specifications so there is a publication request for the data Integrity spec the jws 2020 spec ecdsa 2019 EDSA 2020 and that's it for now.
Manu Sporny: There are other crypto Suites that are listed in the charter where I didn't know if I didn't know who was going to publish them so it's mainly the co Blitz ecdsa one I guess that's or E so I'll let him.
Manu Sporny: Kind of try and try and publish that so we've got three out of the four crypto sweets published so far we're still waiting on the Cobell it's one this is just a heads up number of you participated in some subset of those discussions so make sure to agree to the final specification agreement if that comes across your desk.
Manu Sporny: The recovery crypto sweet I guess is also this looks like it's a diff one do we does anyone at diff know if whoever's in charge of the ecdsa recovery signature 2020 thing is going to publish that as a final report.
Manu Sporny: Like it's listed here but I don't know it's here let me get a link probably should under diff but it does not have an author.
Manu Sporny: And it was listed as one of the optional sweet so I guess we can leave that hang out there until someone claims it I guess from what I remember it was Spruce that wanted that in there if I remember correctly.
Joe Andrieu: The GitHub has contributors.
Joe Andrieu: Looks like Charles Lerner was the last one emerge something in on that.
Manu Sporny: Okay great thank you I'm still looking there we go viewed on GitHub.
Joe Andrieu: That's or a Charles and Ben go if you know Benjamin.
Manu Sporny: Okay yep I've got I've got a line to bend go as well so I'll ask them what their intent is on that particular particular one okay that's it for kind of the heads-up for the publication of those final reports.
Manu Sporny: The end okay any any other relevant Community updates or things of that nature.
Manu Sporny: Joe I've got a rebooting question for you what what.
Manu Sporny: The the format I don't know if the format has really changed there's a lot more time right at this rebooting or it feels like it and I think the last time rebooting happened there were some breaks you know they we're trying to plan enough kind of empty space around the main you know conference do you have any sense on how many things people could work on simultaneously there is there a.
Joe Andrieu: Ha ha ha II do but it's mostly from trying and failing I think the most successful multi paper efforts we've had have been when a group of people have gotten together and together they had several artifacts like hey on this conversation let's talk one that's about generating the signatures and another paper that's about verifying them right so they were connected I failed.
Joe Andrieu: When I had.
Joe Andrieu: He projects because I had somebody wanted to revisit Ameri or your mm and I was doing Saturn and a third one and really only one of them ended up getting published so even and that was also the comic book version of your arm was also so it's really hard to do more than one.
Joe Andrieu: Has been my personal.
Manu Sporny: Okay unless there's like related in some way and there's a lead for each paper or something like that is that the pattern that might work.
Joe Andrieu: Yeah the pattern that that did work was Christopher Alan and wolf McNally had led a team that spit out three or four papers but it was really the the team of six or eight of them working together so there was a because the problem is the conversation if you're not there to have the interesting conversations and you can miss how ideas built or what arguments have already been had you know decisions made so you can move on to some other.
Joe Andrieu: Stir and.
Joe Andrieu: Between multiple groups you often just miss out on that and so it's hard to build simultaneously but when they were in the same room you know for the whole week if you will then those sorts of conversations are more organic and easier to manage.
Manu Sporny: Got it got it got it got it okay all right that's that's very useful and trying to figure out how the I'm seeing a number of papers that could be kind of combined and trying to figure out how if it's better to join them or split them and that and as as you know that's a part of the process when we there.
Joe Andrieu: That's right what that is the the main thing we do on Monday afternoons for those of you who aren't familiar although I think most of the people I'm seeing here have been there but yeah that Monday when people come up with ideas Chris does his magic and says hey these two seem related can we merge them right and sometimes that works out sometimes it doesn't but that's part of the process.
Manu Sporny: Yep okay let's one thank you for that was just pontificating about that.
Manu Sporny: Okay anything else before we jump into use cases.

Topic: VC API Use Case Review (Continued)

Manu Sporny: All right so next up is the VC API use case review over to you Eric and Joe to take us through the remainder of whatever you want to take us through.
Eric Schuh: I believe last week we got at least partially through reviewing 6.4 this use case here aggregated credential workflow because it's a fairly short one.
Eric Schuh: I guess we could.
Eric Schuh: Take a quick look at it if people want before moving on to 6.5 so there's give everyone a couple minutes to read through the use case here and then go down to the diagram kind of following the same flow as last week.
Eric Schuh: Sorry I just realized this is one of the issues with having different PRS for each one is not actually the up-to-date one don't think the text changed.
Joe Andrieu: Was this one we had the questions from Mike.
Eric Schuh: Yes I do believe there's a set of questions for this here.
Eric Schuh: So maybe I'll go to those after a couple more minutes here just to give people time to read through.
Joe Andrieu: And for those of you who weren't here last week you can go to the pull request and do a preview if you want to get this into your own browser and be able to zoom in a little bit that might be helpful.
Eric Schuh: Richard link directly to the preview.
Eric Schuh: And this is 6.4 if you're using the.
Eric Schuh: Table of contents at the top.
Eric Schuh: Okay unless someone stops me I'm going to tab over to the questions that Joe and I developed coming out of this I think it's pretty obvious.
Joe Andrieu: I don't want to briefly stopped you just to be clear there was one slight language in thing but I think I did some big you ate it on step 5 we have display a comma B not found and that was be a was found but be was not as right as opposed to a comedy not found just so what's happening here is.
Joe Andrieu: Is trying to get something from job application and they need to credentials one of which Kenzie doesn't yet have which is his background check I take it.
Eric Schuh: Yes it's specifically I believe from the text up above its that she doesn't have it but her wallet knows how to go and get it automatically.
TallTed_//_Ted_Thibodeau_(he/him)_( That'll be clear if you change the comment to a semicolon.
Eric Schuh: Sure let me.
TallTed_//_Ted_Thibodeau_(he/him)_( It might be even better if it says b was not found.
Eric Schuh: So one thing that I think you should notice if you were here last week is that this diagram is quite a bit simpler I think than the rest and that is mostly because I think if I remember correctly Joe and I read through this version of it and through the text as well as the reference diagram that was in the original.
Eric Schuh: Google Drive document and we came out with this set of questions for this Mike I believe it was the original submitter yeah haven't had haven't heard back from Mike on these questions yet but after we kind of had him chime in as to these issues there was going to be another revision to the diagram itself.
Joe Andrieu: So one know I would add Eric for us to work on is and I think there's probably true of one of the others as well is we probably should review these with an eye to breaking out the holder the holder app and holder service I think this one is conflating the holder app with the holder.
Joe Andrieu: I think that's a must.
Eric Schuh: Maybe more the holder app with the holder service even.
Joe Andrieu: That could also be yeah I think those boundaries are the most immature in the VC API so when we get through this set you and I should look at them together and see where the consistent separations might be.
Manu Sporny: So I've got a question put myself on the Queue is this it so this is an async flow right there's a delay some of the other flows we've been looking at is like all the informations available across the the systems and it's just a matter of getting data from point A to point B and it's done pretty rapidly this one there's a delay in that swear step 16 kind of comes in right it's it.
Manu Sporny: Or wait now so there's where does the delay come in.
Joe Andrieu: I think you're right.
Eric Schuh: I believe it would be actually at 12 as the background this is Step 12 would essentially represent them doing the things they need to do to evaluate the background check so this would be where the time would come in and then once they've decided that it was good they go to their issuer service and get the VC issue.
Eric Schuh: So I.
Eric Schuh: 12 Has the time delay.
Manu Sporny: This is the thing we're well I mean we're fairly.
Manu Sporny: We well I guess we are uncertain whether or not the API supports this kind of behavior today or we're fairly certain it does.
Joe Andrieu: I think we're fairly certain it doesn't.
Manu Sporny: Does it look okay okay.
Joe Andrieu: I think this is super interesting right from requirement standpoint that's what we're trying to tease out and we've got this this call from the issuer app a background check into the wallet and right now it's currently model this directly to the holder service and there's an arbitrary delay right between 12 and 15 and I think exposing this endpoint on the holder service for an issuer is not something we've talked about although I think it fits this this pattern of.
Joe Andrieu: We want to enable web hooks as.
Joe Andrieu: As a general pattern but I think that's a very young idea and I don't think it's well integrated into the API yet.
Eric Schuh: Yeah so one thing I think you'll notice as well as if you go back to the six point three or six point to be ours and look at those diagrams there I think we're mostly using the a callback mechanism so in those ones we would have had this credentials issue call kind of include a callback that could have been used here but I think we were trying to show two different ways where this could be an official and point as well and that's the way you could.
Eric Schuh: Enable the asynchronicity rather than it was.
Eric Schuh: Call back that then this service would have.
Eric Schuh: Keep around for a long time possibly because this could take two days right to evaluate a background check but these end points here which I think we also see a little bit more in the 6.5 we have no call-outs to the to these in the VC API today.
Eric Schuh: Kind of these.
Eric Schuh: And points which could hear it goes to the holder service but I think we also had one going from the issuer service to the issue rap at one point with something like this might say that in a bit.
Joe Andrieu: Yeah I expect that one that one in particular probably deserves to go to the app because the app would have the business logic to decide whether or not we should even accept that VC.
Eric Schuh: Right that's to your point earlier that this diagram isn't doing a good job of breaking that out there conflated here.
Manu Sporny: Okay yeah there's the well I mean we have the exchanger Service as a talking discussion point today so that.
Eric Schuh: Yeah which this could office could definitely feed into.
Manu Sporny: Okay yeah I mean this is certainly great because it does call out requirement you know of the system.
Eric Schuh: Yeah this is where.
Eric Schuh: As we were going through this originally in the visual Paradigm the other program that Joan I used to create these that's why I started to use the stereotypes for calls like this where this clearly does not exist today and it's not really clear if it should exist or if it should exist in a different form.
Manu Sporny: Yeah that that that would be an exchanges and point know the expectation what's this is mapping to in my head is like 11.
Manu Sporny: Some some something that happens before 12 would provide an interactive URL for the holder and then 15 would call that interact URL which is something on the exchanges.
Manu Sporny: App service whatever whatever in the calling it but it's the how do you get back in touch with the holder after you've gotten the background check or tential.
Eric Schuh: But I guess my point was also if anyone that anyone here knows mermaid maybe a little bit better than I do at this point it has an idea for how we could maybe encode some better information about because this credentials issue and point is one that exists today in the VC API documentation where's this one was not it would be nice if that popped out a little bit more from these diagrams it would make them a little more useful I think but it's something I haven't figured out how to do in mermaid well.
<john_henderson> You could add a note in mermaid as well
Joe Andrieu: Yeah I think there's some color stuff I hesitate to rely on color because of ADA but it may be an option that's at least marginally better.
Eric Schuh: Yep might just be something we have to live with but.
Manu Sporny: Yeah we don't have a lot of options with mermaid its markup syntax is kind of it's very limited John raised a good point in the chat Channel which is we can just add a note as well hmm.
Eric Schuh: I don't know okay that might be a might have to look at how to get that in.
Eric Schuh: But any other comments on this 6.4 at this point.
Joe Andrieu: No I what I was thinking of was more generic so I'm sure it'll come back when we look at the next one.
Manu Sporny: In just a organizer notes time box to for another 10 minutes and then move on to the next agenda items if that works for you Eric.
Eric Schuh: Sure yeah I'll move a little bit quicker on this so 6.5 I'll just spend two or three minutes here to read this and then get a quick look at the diagram.
Manu Sporny: What is this thing what is the core thing this this use case is pulling out that's different from the other ones.
Eric Schuh: Yeah so I think that gets to somewhat so Joe and I got about halfway through this use case as far as reviewing it and I think that question was one that is somewhat in the vein of a couple of these.
Eric Schuh: Where we focus more on looking at the initial diagram.
Eric Schuh: Here and just tried to we struggled I think with that question as well.
Joe Andrieu: I just from a quick scan of the paragraph here I think it's that they are using a external allow list for issuer.
Joe Andrieu: I don't think we have that in any of the discussions I don't know that it impacts the VC API much but I think that is the one thing that's different here.
Manu Sporny: So the so the verifier is using a allow list for issuers to determine whether or not they accept the credential.
Joe Andrieu: It is in real-time check we checking a state accreditation system which maintains the allow list.
Manu Sporny: That yeah I mean that that certainly has value I mean yeah that has value from protocol perspective because we do expect things like that to happen.
Manu Sporny: I mean it has more to do with allow lists you know the issue or allow less than anything else so you could argue that that's not really part of the VC API except that the protocol would need to reach out and get that kind of stuff.
Joe Andrieu: Yeah I think it's a great boundary question about you know what is the what are the bounds of the VC API and Does it include this very common use case of a I know I need to go check some system so do we standardize that or not and I think it's a fair game to argue either way within the within the working group.
Eric Schuh: Okay I think I'll leave people if they want to look at the diagram in more depth this is I think one of the more complicated ones in the set I just as far as how many different entities get involved throughout this use case so.
Eric Schuh: Just for the time box moving on to 6.6 the length of the pr in the chat.
Joe Andrieu: Oh yeah that's weird.
Eric Schuh: Note here I don't know what happened to the mermaid renderer with this one because when I put it into an external mermaid render I got this image and everything seemed to be okay so I don't want to spend too much time here just because this is a pain to read but just to give everyone a chance to take a look at the text for now.
Eric Schuh: I'll just spend two minutes here and then we can have whatever discussion we want and call that the end of the use case review.
Joe Andrieu: I have a medical question that many of you might be able to help with is there a way we can inspect the error that might be generated by this mermaid.
Manu Sporny: Yes yeah okay if you just bring up the JavaScript console it should have printed it out on the on the console.
Manu Sporny: And if not it throws at some point and we could look at that.
Joe Andrieu: Yeah I'm just saying the fav icon complaint.
Manu Sporny: Yeah same here so it's not actually crashing.
Manu Sporny: Oh yeah I will have to take a look my eye yeah I'd have to take a look at that.
Joe Andrieu: Like clearly don't need to solve it right now but I'm sure it's an extra semicolon or misplace quote or something but and a hard hard to debug.
Eric Schuh: I guess does anyone have any comments or discussion based off of the text here unfortunately.
Joe Andrieu: It's hard to parse do you remember what was what was interesting or different about it.
Eric Schuh: Um let's go see what the notes were back here.
Eric Schuh: So it was mostly the automation I believe.
Eric Schuh: That's really what this use case gets to for the most part.
Joe Andrieu: Is the the customers release come back as a VC.
Eric Schuh: I believe that's how I did it in the updated diagram yes but this is what I was working off of so what was intended is another question you and I haven't gotten around to reviewing this one Joe so we have a generator generated our questions yet.
Joe Andrieu: It seems similar to my car lease in that multiple VCS are being combined to get a yet another PC so I'm curious maybe the automation aspects are different but I think those are some of our questions for Mike as well like what exactly is being automated here and who is the authority to establish and monitor those authorizations.
Manu Sporny: Yeah I'm I'm looking in the traceability vocab right now and there's a PGA shipment status code released so it's looks like.
Manu Sporny: There is a VC for whether or not the thing spin or least.
Eric Schuh: I want to make a note.
Manu Sporny: Me find the link to that real quick here's the PGA shipment status that they have.
Eric Schuh: But if there's no other comments why do I think back to you for issues.
Manu Sporny: Okay great thank you Eric and and Joe at this point does anyone have any objections to marching this stuff into the document once you know Eric and Eric and Jo do another pass on it.
Joe Andrieu: And this is will be the use case document just to clarify right not the main document in case we were concerned.
Manu Sporny: Yep sorry yep yeah that's that's right yeah merging this into the use cases document does anyone have any concerns about doing that at least at a conceptual level right now.
<tallted> Further iteration will just shift from comments to PRs.
Manu Sporny: Okay all right well I mean y'all should feel free to merge after you've done whatever editorial fixes you feel are necessary thank you again a ton for working on those things and in documenting it there is a question around how that stuff gets moved into the VC WG I think there are a number of people that are kind of building to suggest that we move VC API NBC API use cases into the V CW G.
Manu Sporny: Earlier than sooner than later just so that it's.
Manu Sporny: Going to be.
Manu Sporny: And it's still a kind of an open conversation around whether or not we are going to continue these calls or whether these calls would become a special topic call for VC w g or things of that nature.
Manu Sporny: I am gay and I think that's a conversation that we're going to have in the be cwg not necessarily here I think this is just a heads up to this group that are stuff might be pulled in and sooner than later or at least snapshotted sloot sooner than later.
Manu Sporny: That's it any questions concerns about that.
Manu Sporny: Before moving on.
Manu Sporny: Right next item up is what if folks want to do you want to talk about it ox or do you want to talk about the exchange of service any preferences.
Manu Sporny: I see.
Manu Sporny: North is it might impact the jff work.
Manu Sporny: Go ahead Joe.
Joe Andrieu: I just meant to give the thumbs-up so.

Topic: Specify DIDAuthentication protocol in more detail

Manu Sporny: Okay okay let's talk about did off then if there are no objections there's an issue raised to specify the did Authentication Protocol in more detail in the let me go ahead and share my screen because there's some concrete suggestions Troy and make this a bit bigger so people.
Manu Sporny: So the this this also does have to do with the VP request spec which is being used by the VC API right now in the tests and things of that nature we are very light on details around did off and we have always kind of been light on details around that so this is a suggestion that we need to start getting very specific and give give people something concrete to implement against their.
Manu Sporny: Has been the section on.
Manu Sporny: Back for a while now but it's again it's been it's been light so the simplest form of did auth you could argue is just a verifiable presentation request where the query is of type did authentication you provide a challenge I think the domains wrong you don't provide a domain the center provides a domain well that well actually there's there's a discussion.
Manu Sporny: Russian item around that but maybe.
Manu Sporny: Lie to me and maybe you don't and then you provide a service in which the entity can interact so where do they send the did authentication presentation where they send that back and there's a URL and point to send it back to the VC API so so this is basically like I don't this is basically saying I need you to dot I don't care what did method you use I don't care which crypto sweet you use here's your challenge and do.
Manu Sporny: Main generator.
Manu Sporny: Writes pretty open-ended there's another part of did off here which basically says I want you to did off but I actually care quite deeply about the did method that you use and the crypto sweet use so I only accept did Ott's using did web in you need to use an ecdsa signature sweet right so and standard nist crypto everything else.
Manu Sporny: Kind of Remains the Same but this is.
Manu Sporny: Scalise saying I want you to did off but with did web in with an ecdsa signature the third item is more complicated still this one is the same thing I want you to did off in this is effectively me let me this is an A and so I want you to let's see I want you to did off.
Manu Sporny: Multiple things right so I want you to do it off with did web so prove to me that you have you can do a nest.
Manu Sporny: I want you to also simultaneously did off with BBs + so prove to me that you can do selective disclosure / unlink ability and I want some kind of assurance from your digital wallet provider or a pseudonym pseudonymous version of that that you have multi-factor authentication into your wallet at some point in the next in the last eight hours.
Manu Sporny: Or whatever right.
Manu Sporny: So this is actually asking you to did off in to get some Assurance from your digital wallet that you've you meet some minimum multi-factor level so all three of these examples are.
Manu Sporny: At least our customers and there's a question of like okay well do we want to support things like like first what's the name of the type S do we want to be able to specify the did method third do we want to specify the crypto sweet and then this thing is probably separable meaning do we want assurances from someone that you've authenticated in a way we have multi.
Manu Sporny: Okay so let me let me stop there the fundamental question is do we want to specify do we want to spend some time specifying did off in more detail and create a PR for that.
Manu Sporny: And put yourself on the key of the.
Manu Sporny: I had to meet Ray.
Manu Sporny: You're muted Dimitri.
Dmitri Zagidulin: So in terms of said we specified it off I think so.
Dmitri Zagidulin: Because it is a key part of much of issuing use cases possibly verifying but definitely issuing.
Dmitri Zagidulin: I'm so that's that's answer that question I definitely recommend that we do tests on my other question was doesn't make sense for us to specify or at least illustrator mention inspect the methods of transmission of challenge so good to give an example one of the things that DC see that were running into in the issue.
Dmitri Zagidulin: Is an exchange endpoint for.
Dmitri Zagidulin: For an issue stuff.
Dmitri Zagidulin: It's a mobile app and so the question becomes how.
Dmitri Zagidulin: How does the issuer communicate the challenge to the to the wallet in order to perform the did authentication so that the issuer can issue the credit so it makes sense.
Dmitri Zagidulin: We're like we're going to recommend like scanning the QR code or following the Deep link but I wanted to make sense to mention any of those things in the in vcat.
Manu Sporny: If anyone else has thoughts please put yourself on the queue.
Manu Sporny: Ahead Joe oh in sorry Marcus how old is that Q.
Markus Sabadello: It's it's new but.
Manu Sporny: Go ahead and Marcus I'm sorry I didn't see you jump on the queue.
Markus Sabadello: Yeah I'm also generally interested in theater off and what else is apart exploring that further I'm not so very familiar with VP request specification so I assume there's a bit of work there that's that's relevant here I think I remember some earlier versions of this did off request and response where.
Markus Sabadello: I think at some point.
Markus Sabadello: Concept of a claim about your public key right there was the credential subject which was your date and then one of the claims was the public key so you're making a claim about what your public keys and then you're adding a prove to that looking at this it seems like it has changed a little bit but as I said I'm not fully up-to-date with verifiable presentation request specification and.
Markus Sabadello: Just in general I.
Markus Sabadello: Interested in this and support exploring this.
Manu Sporny: Thanks Marcus you are remembering correctly and I believe that still there we just need to detail it out the previous plugfest sees that that kind of mechanism in some of the use cases go ahead Joe.
Joe Andrieu: Yeah I wanted to introduce the notion of the VC and bedding perhaps in the evidence property some form of the did off that was performed to ensure that the subject ID was under the control of the party that the VC was issued to I think it's a pretty natural use case it may be as expensive in terms of the size of the VC but I think in some of you.
Joe Andrieu: Cases it's worth it and having a.
Joe Andrieu: Way to do that feels like a pretty easy lift.
Dmitri Zagidulin: That so the question for Joe about that particular use case so at the moment.
Dmitri Zagidulin: The Facebook verifiable presentation serves that use case.
Dmitri Zagidulin: Saying so the proof of did off comes in the wrapper to the D.C.'s not in the disease itself so my question to you is is that sufficient for our use case or would you also want to see it in the DC proper.
Joe Andrieu: I would like to see in VC proper one of the ways that I frame this when you know doing educational stuff for folks on this is really the the identity Assurance happens because you dude it off before is issued and then you do did off upon presentation and now we know that that party actually had access to at a minimum the secret that allowed them to do did off at two points in time.
Joe Andrieu: So it's really a codification of what I think is a best practice right now which is doing a did off before you issue to verify the the recipient is giving you an ID that they actually control.
Dmitri Zagidulin: Right but the best practice or at least in the.
Dmitri Zagidulin: The deployments that I've seen the best practice confirms the control of the did in the presentation not the VC.
Joe Andrieu: And and and before so the projects you and I have been on together rather than potentially bring in those names or companies or brands or whatever you know a prior to issuing the VC there was a did off to communicate the d i d that is actually going to be the subject in that VC.
Dmitri Zagidulin: Jack yeah I'm not done through a VP.
Joe Andrieu: Yes so but but it's a different VP that is a VP with no VC in it that's a did off before you issue the VC and and what I'm advocating for is that in that VC we could embed something that lets us know that that did off before issuance confirmed that the subject controlled that ID.
Joe Andrieu: It could be just embedding the VP of that initial did off like that's the naive solution I don't know that's the best solution but you couldn't just include the VP that was your did off back and forth.
Manu Sporny: Yeah I put myself on the Q yeah this is that's that's fascinating Joe I think the thing that we get out of this I think this is a great idea the thing that we get out of this is that the verifier no longer has to presume that the issuer checked they have cryptographic proof that the issuer got the subject to did auth.
Manu Sporny: Before they issued.
Manu Sporny: VC in the verifier that's one less thing the verifier has to wonder about they don't have to wonder about like did they actually do a did often with this did before to the subject before they issued the VC or did they mess that step up in this is actually assigned to you know something that doesn't make sense go ahead Dimitri.
Dmitri Zagidulin: So as a Counterpoint to that the current setup.
Dmitri Zagidulin: Assumes that the verifier that the very final presentation.
Dmitri Zagidulin: That the holder uses to hand over BC to the verifier includes did off the includes a proof of the holder and that's how the verifier knows that the subject of the BC is the same entity handing it over.
Dmitri Zagidulin: What do you mean.
Joe Andrieu: But you don't because you know just of prison fallacious scenario you could go get a VC with my ID and if they never do a did off before they give you that VC then you may be able to do all sorts of things to convince the issuer that you're me and then now my my wallet has the idea.
Joe Andrieu: Has control over the ID.
Joe Andrieu: Later in the process so in fact you got the VC you got an issue to my D and therefore the secondary singular check is not actually verifying what you think is verifying.
Dmitri Zagidulin: I'm not sure I fully understand if I stole your VC how would I be able to prove control to the verifier.
Joe Andrieu: No no you didn't steal my VC you went to the issuer and created a VC using my did.
Joe Andrieu: And the issuer accepted whatever song and dance you gave them that that was a good idea or they just didn't check they didn't bother doing it DID Auth and so when I go and present that VC because somehow you gave it to me we're not actually proving that the person who received the VC initially is the person who's presenting it.
Dmitri Zagidulin: Wait but that wasn't the claim that I was saying that their fact can check that the subject is the person presenting it the who received it doesn't really matter in our trust model.
Joe Andrieu: It may matter.
Manu Sporny: Yeah in some trust models it matters in others it doesn't write this is I think this is an important thing that we should dig in on but I guess I'd like to noting we've got five minutes left do we have any objections to trying to detail I did often in a bit more detail in the VP R-Spec.
Joe Andrieu: Now I think it's important to tease out DID Auth for the VC API to be wholly formed.
Manu Sporny: Okay then what we will do here if there are no objections we are needed detail add detail to the authentication it or not.
Manu Sporny: Protocol and the messages in the VP our specifications specifications such that it's usable in the VC API specification add notes around where did the topic that you're the topic you're raising Joe is more of like an Evidence pop property best practice thing so we can.
Manu Sporny: An add an.
Manu Sporny: The VP R-Spec that says hey you really should include you know where we're currently exploring whether or not it's a good idea to add the initial did off in the for the issuer to include the original data Earth in the evidence property of the credential that's issued we're exploring that like where would that that feels like we should.
Manu Sporny: Feels like.
Manu Sporny: Belonging to be cwg as an issue there how about this I'll write in trial add issue marker around including.
Joe Andrieu: So I think there is an issue so let me go see if I can find it and we can bubble it up.
Manu Sporny: Okay and then I can I'll add an issue or whoever does the pr if they get to it before I do add an issue marker around including the around the issue or including the initial initial it ought presentation as evidence in.
Manu Sporny: A VC that they issue.
Manu Sporny: We have three ish two minutes left any other items that folks would like to briefly mention before we end the call this week.
Manu Sporny: Okay that's it for the call this week thank you everyone for the discussion today we will meet again next week with a new set of issues to discuss thanks all bye.