Fwd: [MINUTES] W3C CCG Verifiable Credentials for Education Task Force Call - 2022-04-18

> Begin forwarded message:
> 
> From: CCG Minutes Bot <minutes@w3c-ccg.org>
> Subject: [MINUTES] W3C CCG Verifiable Credentials for Education Task Force Call - 2022-04-18
> Date: April 21, 2022 at 1:53:36 PM EDT
> To: public-credentials@w3.org
> Resent-From: public-credentials@w3.org
> 
> Thanks to Our Robot Overlords for scribing this week!
> 
> The transcript for the call is now available here:
> 
> https://w3c-ccg.github.io/meetings/2022-04-18-vc-education/
> 
> Full text of the discussion follows for W3C archival purposes.
> Audio of the meeting is available at the following location:
> 
> https://w3c-ccg.github.io/meetings/2022-04-18-vc-education/audio.ogg
> 
> ----------------------------------------------------------------
> VC for Education Task Force Transcript for 2022-04-18
> 
> Agenda:
>  https://lists.w3.org/Archives/Public/public-vc-edu/2022Apr/0020.html
> Topics:
>  1. IP Note
>  2. Call Notes
>  3. Introductions & Reintroductions
>  4. Announcements & Reminders
>  5. VC Governance
>  6. PDFS as VCs with James Chartrand from McMaster University
>  7. Credential Display in Wallets Discussion
> Organizer:
>  Kerri Lemoie
> Scribe:
>  Our Robot Overlords
> Present:
>  Kerri Lemoie, James Chartrand, Stuart Freeman, Deb Everhart, 
>  Brandon Muramatsu, JeffO Real-IT, Geun-Hyung, Simone Ravaoli, 
>  Marty Reed, Dmitri Zagidulin, John Kuo, Andy Miller, Keith, Phil 
>  L (P1), Nikos Fotiou, Yashwardhan, Leon, yashwardhan, G, Alan 
>  Davies, Colin (LEF), Kayode Ezike, David Chadwick, Jim Goodell, 
>  Kaliya, Timothy Summers
> 
> Our Robot Overlords are scribing.
> Kerri Lemoie:  Hello welcome to the VC edu task force call on 
>  Monday April 18th I'm today we are going to be discussing 
>  credential display in the wallets including PDFs and also a quick 
>  touch base on VC and VC Edu governance.
> 
> Topic: IP Note
> 
> Kerri Lemoie:  I'm for we get started let's start with the IP 
>  note anyone can participate in these calls everyone is welcome 
>  however any substitutive contributors to any of the ccg work 
>  items including this task force must be done by members of the 
>  ccg with full IP our agreement signed in you can learn more about 
>  this at this link that I'm going to put in the chat right now.
> Kerri Lemoie: https://www.w3.org/community/credentials/join
> 
> Topic: Call Notes
> 
> Kerri Lemoie:  Hey for call notes these minutes well this isn't 
>  that these meetings are recorded an audio recording done for 
>  every call as much as we can do this but they're also transcribed 
>  by the robot overlords and you will see in the chat the job that 
>  they are doing as we speak if you see that there is anything that 
>  could be corrected that's being transcribed improperly please do 
>  us a favor and.
> Kerri Lemoie:  You see it do a.
> Kerri Lemoie:  Substitution and the chat and you can do that by 
>  typing s /i'm phrased to fix or word and then fix phrase I'll put 
>  that in the chat as an example.
> Kerri Lemoie: Example: s/phrase to fix/fixed phrase/
> Kerri Lemoie:  I'm sure that as I speak robot overlords and I 
>  don't always get along well so I'm sure we will see lots of 
>  examples of that please note that we do use a cue system and 
>  these calls so if you have something to say or question to say 
>  please type Q the letter Q & A plus sign farewell adieu to the Q 
>  and if you feel as though your kids your mind you can type Q - 
>  and I will remove you from the queue by doing.
> Kerri Lemoie:   I'm this we will.
> Kerri Lemoie:  At the Q and then call on you in order.
> 
> Topic: Introductions & Reintroductions
> 
> Kerri Lemoie:  Okay why don't we see first is there anyone here 
>  who's new to the call or who like to make an introduction of 
>  themselves today or anyone who's been in the call for a while and 
>  would like to reintroduce themselves or have some news to share 
>  Dimitri you're in the cube.
> Dmitri Zagidulin:  Hi can you hear me okay.
> Dmitri Zagidulin:  So yeah I thought I'd do a quick 
>  reintroduction only because one of my hats has changed so I have 
>  recently reduced my work with digital bizarre do I'm still in 
>  close collaboration with Angela's our team and have stepped up my 
>  involvement in virtual reality and augmented reality so I'm still 
>  doing the same things verifiable credential.
> Dmitri Zagidulin:  Decentralized identifiers Secure Storage just 
>  bringing that toolbox to the AR and VR world still also involved 
>  in digital credentials Consortium and the learner wallet there 
>  that's it.
> Kerri Lemoie:  Thanks Dimitri that sounds incredibly exciting 
>  that's awesome.
> Kerri Lemoie:  Anybody else have would like to make an 
>  introduction or update us on your current work.
> 
> Topic: Announcements & Reminders
> 
> Kerri Lemoie:  So next we have announcements and reminders keep 
>  in mind that every Tuesday at noon Eastern is the ccg call and 
>  that is always worth checking out if you have time to do so to 
>  stay up to date on what is going on overall in this community.
> Kerri Lemoie:  I'm also next week is the internet identity 
>  workshop and that starts on Tuesday this Tuesday through 
>  Wednesday or is this Tuesday Wednesday I think but it's next week 
>  and that means that we will not have a call next week so next 
>  Monday there will be no VC I'd you call I'll send an email 
>  reminder out but I just want to let you know they were going to 
>  skip next week because some of us will be at that meeting and 
>  we'll be able to do this as well are we traveling that day.
> <jeffo_real-it> IIW is  Tues, Wed Thurs - Sodl out apparently.
> Kerri Lemoie:  Just check the queue here see if we have.
> Kerri Lemoie:  I'm sorry I let sold out incredible thank you.
> <jeffo_real-it> 250 cap
> 
> Topic: VC Governance
> 
> Kerri Lemoie:  So before we get started with James we have Jim 
>  chartered in here who's been doing some interesting work on PDFs 
>  as we seize I was here from McMaster University and I'm just 
>  going to fill us in on that work you may have seen some 
>  descriptions of this and the mailing list and we thought it would 
>  make a lot of sense to ask him to come tell us and every CH you 
>  you know what how they've gone about doing this PDFs is something 
>  that open badges has discussed for a long time it also has come 
>  up quite a bit in this community.
> Kerri Lemoie:   You before there's a whole lot of reasons to use 
>  PDFs in education.
> <jeffo_real-it> If anyone wants IIW ticket check in any case just 
>  in case.
> Kerri Lemoie:  I'm there there are well understood format and you 
>  know and can be secured and have embedded data in such as James 
>  will tell you and then we're going to talk more about a 
>  credential display and wallets and then I'm gonna have to meet 
>  you just helped lead that discussion to you because he has some 
>  things in mind but before we get started if you don't mind I just 
>  I wanted to ask you all to take a look.
> Kerri Lemoie:   At this mirror board.
> Kerri Lemoie: https://miro.com/app/board/uXjVO8bG_9s=/
> Kerri Lemoie:  The chat and I will share my screen when one thing 
>  that we have been talking about or thinking about a lot is what 
>  is governance right what is governance in this space.
> Kerri Lemoie:  A lot of misconceptions and a lot of questions and 
>  I really hope to be able to push on this topic more at internet 
>  at the iaw next week and so I'm hoping that I could do some 
>  research with folks in this community before we go to see what 
>  kind of assumptions and questions and understandings that you 
>  have about about what governance is so although I'm not a huge 
>  fan of Mero I feel like this is a good place to do this because.
> Kerri Lemoie:   You can bring it whatever you'd like whenever you 
>  want if.
> Kerri Lemoie:  We need another section other than assumptions and 
>  questions go ahead and create that you could do what you want 
>  with this board and then we'll take a look at it at the end of 
>  the week or early next week and and see what we're learning in 
>  here and what you know of questions and assumptions we should be 
>  addressing.
> Kerri Lemoie:  And before I move on I sort of want to check in to 
>  see if anybody would like to talk about that now if they have 
>  anyone has any questions about this or any sort of like it's up 
>  to some questions you'd like to bring up right now before we even 
>  get into our main topic.
> Kerri Lemoie:  You I will start an email thread on this later 
>  today and then feel free to respond to that and add whatever 
>  you'd like to this board also feel free to reach out to me 
>  directly if you'd like to just talk about it some more I am I 
>  don't have a lot of understanding of what governance is I've seen 
>  it implemented in various ways and I've heard of some really 
>  interesting ideas for Registries Registries and things of that 
>  nature I've also heard a lot of.
> Kerri Lemoie:  Fusion between what accreditation is and what VC 
>  governance is and so I thought it would be a good idea for us to 
>  really gather as many questions that assumptions as we could so 
>  we can start tackling this over the next couple of months.
> Kerri Lemoie:  Critic you some tea so James like to write you to 
>  participate and and present what you have for us I will stop 
>  sharing my screen so you can do that like you.
> 
> Topic: PDFS as VCs with James Chartrand from McMaster University
> 
> Kerri Lemoie:  How you doing James nice to see you.
> James Chartrand:  Okay thank you I'm good yeah.
> Kerri Lemoie:  One thing you might want to do James's turn off 
>  your video because we've been having some problems with memory 
>  issues the jitsi and I'd love to record as much of this as 
>  possible so.
> Kerri Lemoie:  Awesome yes thank you.
> James Chartrand:  Yeah I just turned it on for a sec so people 
>  can see what I look like here we go sure so share my screen.
> James Chartrand:  Sorry I'm looks like I'm having to go through 
>  and.
> James Chartrand:  So it's I'm going to have to restart but I will 
>  be right back.
> Kerri Lemoie:  Okay Dimitri while we're waiting for James to come 
>  back to you want to sort of approach to subjective credentials 
>  displays and wallets.
> Dmitri Zagidulin:  Sure yeah so with invisi edu here we've got 
>  two pressing problems that we need to solve we've got to pain 
>  points one is so we have these verifiable credentials that are 
>  going to be displayed in wallets but we also would like.
> Dmitri Zagidulin:  To bind them to more traditional display 
>  artifacts such as PDFs and that's what James is going to be 
>  talking about and then the second one is also on the subject of 
>  display slightly different somewhat related we want issuers to be 
>  able to specify exactly or at least advised to wallets verifiers 
>  and other software how to display the credential because at the 
>  moment every single wallet everything would be so.
> Dmitri Zagidulin:   A soft fire.
> Dmitri Zagidulin:  On in the DC world is some way out now there 
>  have been precedents in for example open Badges and and some 
>  other VC projects that have used things like embedded images to 
>  specify how the credential should be displayed and that's that's 
>  the other topic that would like to touch on today but James is 
>  back so over to you.
> James Chartrand:  Okay so maybe I'll just get a very quick bit of 
>  background so this is a project at McMaster University and it's a 
>  joint project between the faculty of engineering and the office 
>  of the registrar there they got into SSI a couple of years ago 
>  and started out with lock certs so kind of one of the precursors 
>  to I guess verifiable credentials and we at the time started out 
>  with a very.
> James Chartrand:   It's a relatively small pilot.
> James Chartrand:  Like like 50 students where we issued 
>  certificates so not degrees and they were issued to the students 
>  as a batch and went into the block search wallet and that's where 
>  the student held the certificate and they would share it from 
>  there and it was all Json that went very well we then went and 
>  decided to do degrees so issued for very small cohort of students 
>  maybe 50 students in the faculty of engineering their actual 
>  degrees again they.
> James Chartrand:   They lived in the block search wallet and the 
>  students shared their.
> James Chartrand:  That also went very well and then when covid 
>  hit the registrar thought and so when covid hit there were a lot 
>  of problems Distributing will they were alone all sorts of 
>  problems but among them was Distributing the degrees the paper 
>  copies of degrees to students so rather than mail out all of the 
>  copies the university decided to also offer the option to get the 
>  digital copy of the block.
> James Chartrand:  Shorts and they open that up to.
> James Chartrand:  And remarkably that went very well as well and 
>  there was massive uptake it was 80 something percent of students 
>  chose to download a copy of their degree everybody was super 
>  happy with it blocks Arts was great but at that time as a result 
>  of our work we kind of got introduced to the DCC and eventually 
>  joined the DCC and from there we're introduced a verifiable 
>  credentials and.
> James Chartrand:   Centralized identifiers so wanted to move.
> James Chartrand:  Our prior blocks our system to verify with 
>  pensions and decentralized identifiers we also wanted to move off 
>  of the Bitcoin blockchain which is where we've been just where 
>  our blocks our system anchored hashes of the credentials and we 
>  wanted to move off for a couple of reasons one is gdpr and 
>  similar kinds of privacy laws where it seems It's not entirely 
>  clear but it seems at times as though even hashes aren't allowed 
>  on a blockchain.
> James Chartrand:   For us with the degrees it was fine.
> James Chartrand:  As the degree information is public information 
>  and so the fact that somebody got a degree from McMasters public 
>  information and so you know we thought it was decided that that 
>  was okay to put that up permanently on the Bitcoin blockchain 
>  even even though it was just a hash anyhow also wanted to get off 
>  the Bitcoin blockchain because we wanted to move from a batch 
>  issuance which is what we're doing with blocks hurts where you 
>  know the entire cohort at graduation time so thousand.
> James Chartrand:   It's whatever would all get their degrees at 
>  once.
> James Chartrand:  It was all a Merkel took all the credentials 
>  were hashed together into a Merkel and the Merkel was put up on 
>  the Bitcoin blockchain and so that made it you know affordable 
>  but with Rising transaction costs on blockchains like Bitcoin and 
>  fact that we wanted to move to an on-demand issuance system where 
>  a student could request and get their credential or degree 
>  immediately but if we were to Anchor every one of those on the 
>  Bitcoin blockchain.
> James Chartrand:   The cost would become likely.
> James Chartrand:  Exorbitant so anyhow we wanted to move to 
>  verify the credentials decentralized identifiers talked to the 
>  registrar thought maybe we should start with a pilot again she 
>  suggested this is Melissa pool is the Registrar of McMaster very 
>  forward-thinking registrar she suggested that we take a look at 
>  letters that the registrar's office issues to students to confirm 
>  basically student status in different ways so like the letter 
>  that you see up there on the left which control confirms the 
>  enrollment details.
> James Chartrand:   Or student so these are letters that students 
>  use say when they're applying.
> James Chartrand:  Job if the letter say says that they've earned 
>  their degree they are also used but things like getting a better 
>  student bank account freeing up money from your student savings 
>  plan or incoming foreign students might use one of these letters 
>  when they're applying for a Visa coming into the country.
> James Chartrand:  And so we thought great and initially we 
>  thought okay we'll just do it the same way will issue Json copies 
>  so you know the actual verifiable credential as Json to the 
>  student and it will live in a wallet but we in talking to some of 
>  the people in the registrar's office realized that just wasn't 
>  feasible because these letters are often they pretty much need to 
>  be PDFs because of how they're used so.
> James Chartrand:   In some cases they're uploaded as.
> James Chartrand:  Application process say if you are applying for 
>  a Visa and you need to upload a letter confirming your status the 
>  system will only take you know an image or a PDF and that's later 
>  reviewed by somebody who looks at it so if it had been Json they 
>  wouldn't you know it would be nonsensical to them and they 
>  wouldn't know what to do with it also sometimes the letters do 
>  need to be printed off and handed to somebody like say when a 
>  foreign student is riding in the country and the way it works in 
>  Canada is you.
> James Chartrand:   To process your visa application as you as you 
>  step off the airplane.
> James Chartrand:  Typically you've got all your papers you know 
>  you know folder and you present them to the agent the agent goes 
>  through them and reviews from them decides yay or nay so it had 
>  to be printable as a paper copy okay so I will take you very 
>  quickly through what we've built here this is totally integrated 
>  into the Microsoft Azure authentication system on campus and 
>  draws data from a back-end PeopleSoft system.
> James Chartrand:  Go to this web browser on the right this is 
>  where the student would write this again is just a pilot nothing 
>  here is in production and the dire warnings there are because 
>  rightfully so the registrar is concerned that we don't want 
>  anybody to think that this is the system that's being used at 
>  McMaster University because then you could imagine scenarios like 
>  the student arrived a student arriving at.
> James Chartrand:   The border agent of the.
> James Chartrand:  Thanks this is what they should thinks that 
>  they should be getting a copy of a letter like this with a QR you 
>  know and then doesn't accept one without a QR so we're being 
>  extra careful not to make anyone think that this is a production 
>  system okay yeah so I am here I'm a student I will login.
> James Chartrand:  I will request a letter we've got the red star 
>  chose four different letters I'll choose confirmation of status 
>  so that kicked off a dynamic process in the background it pulls 
>  the information from the PeopleSoft system based on the student 
>  login ID assembles the PDF letter I'm using I think Jace PDF some 
>  kind of JavaScript PDF library to construct it on the Fly insert 
>  the information at the same time.
> James Chartrand:   I turn the information into.
> James Chartrand:  The information into a verifiable credential 
>  then into a verifiable presentation then use digital bazaars 
>  amazing libraries and be pqr to produce the QR code which I then 
>  insert into the PDF which you can see down in the bottom right 
>  hand corner of the letter on the left hand side and then return 
>  it to the student so it's been downloaded and it's in my 
>  downloads there I will show you a and so anyhow it corresponds 
>  exactly to the letter that you see on the left here.
> James Chartrand:   Now the student can of course take.
> James Chartrand:  In email it to somebody that can text message 
>  it to somebody they can do whatever they want to with it they can 
>  use it as many times as they want to so say they emailed it to me 
>  and I'm an employer I can come to this website potential Sonic 
>  Master don't see a pretty much have to know in advance that 
>  that's the website to which I should go and of course you know 
>  I'm sure people rightfully point out here that there are 
>  significant problems with this among them are that.
> James Chartrand:  Um somebody can fake the verification website 
>  but I think that's a general problem in any case assuming I know 
>  to go to credentials dot McMaster C.C a I arrived there I choose 
>  verify letter I will choose to upload a letter file I choose the 
>  file upload and it does its verification on you know the usual 
>  way of extracting the BC from the qur an and then doing the 
>  verification one kind of interesting thing that happened there is 
>  that.
> James Chartrand:   What I did what the code did and first of all.
> James Chartrand:  That code is running entirely in the web 
>  browser there's there was no call back to the server there so it 
>  took the it was another JavaScript library that took the PDF 
>  opened it up found the QR image inside the PDF and then from 
>  there and vote the digital bizarre libraries to extract the VC 
>  and run the normal verification okay so that was one kind of 
>  verification now I will show you.
> James Chartrand:  Printed copy of that letter the sitting on my 
>  desk here and I've got my phone hooked up which you can see on 
>  the left so I will choose sorry so I'm going to go over here to 
>  my phone and it's the same webpage this time I will choose her if 
>  I let her again and I will choose scan QR on letter L.
> James Chartrand:  And again at 35 exactly the same way and that's 
>  it that's it's a super simple system which you know we kind of 
>  figures one of the appealing parts of it there's it's dead simple 
>  so extremely easy to use some of the challenges that we still 
>  face or that I guess we Face our somebody could fake the PDF so 
>  they could change some of the details that are within the PDF we 
>  kind.
> James Chartrand:   Dove deal with that a little.
> James Chartrand:  By virtue of the fact that the entire that 
>  sorry what's in the BC that's in that QR code contains the 
>  critical information that somebody would want to verify so up 
>  there on the left and my phone you can see that the down below it 
>  says undefined undefined because we're blanking out student 
>  information for this and it says is registered at McMaster 
>  University is a full-time undergraduate student for the 2028 term 
>  so it.
> James Chartrand:  I was there what was inside the veritable 
>  verifiable credential So what had been signed and you know 
>  doesn't show.
> James Chartrand:  What was in the PDF nessus I mean it is what's 
>  in the PF but it's only what was in the verifiable credentialing 
>  confirmed but of course somebody could take the entire PDF and 
>  they could put a fake QR code on there and they could provide a 
>  fake link and if somebody didn't know to go to the McMaster web 
>  page to verify this they would they could very easily be fooled 
>  the other thing that we would very much like to do is to start to 
>  move.
> James Chartrand:   From these letters.
> James Chartrand:  Towards something more like a student ID 
>  because what we've got here is effectively a student ID I mean it 
>  declares the student status but we'd like to take a you know a 
>  little step further and start to use it within a wallet like the 
>  DCCC wallet as a replacement for the plastic student card in 
>  which case we would have to put more information into it and in 
>  particular would have to put a student photo into it and at that 
>  point.
> James Chartrand:   Point the verifiable credential would be.
> James Chartrand:  It inside a QR code so this is where I think 
>  Dimitri was talking about this a little bit before I got started 
>  that we need to start to think about how we can transfer some of 
>  that information and one way is maybe to create a kind of 
>  ephemeral storage for the full DC and the QR code simply points 
>  to that storage and it might be encrypted as well and we passed 
>  the key to the verifier so anyhow different kinds of things to 
>  start to look at after that and that works out well because I'm 
>  done no I.
> James Chartrand:   I know it's great you're going to restart it 
>  but.
> Kerri Lemoie:  Sorry about that I'm not going to start the 
>  recording but the transcriber we'll keep going so we'll take it 
>  from there thanks.
> James Chartrand:  So I am is so any questions that anybody has 
>  feel free.
> Kerri Lemoie:  Don't see any questions in the queue right now 
>  James what are some common questions that you've gotten besides 
>  say the QR code issues and the faking of PD PDFs.
> Kerri Lemoie:  Or have you already covered those terms of what 
>  you told us excuse me.
> James Chartrand:  Yeah I think I covered them.
> Kerri Lemoie:  Okay I do see Phil Long in the queue so I'm gonna 
>  call in fill her.
> <yashwardhan> what was the acceptance level of administration?
> <keith> I think its a great solution bridging the legacy world 
>  with the new digital world.
> Kerri Lemoie:  Phil Long you have a give the floor if you can 
>  hear us.
> Dmitri Zagidulin:  And you're speaking you're muted.
> Kerri Lemoie:  Yes okay why don't I call on Marty Marty you have 
>  the floor and can come back we'll add them back to the queue.
> Marty Reed:  Sure thanks James for this question a couple 
>  questions one you know how do you how do you handle revocation 
>  or.
> Marty Reed:  Or how do you handle versioning or do you is that 
>  part of this.
> <kerri_lemoie> @yashwardhan - I'll ask your question next
> James Chartrand:  The simple answer is it's not part of it the 
>  idea with these legs and this is one of the reasons that we chose 
>  the letters as kind of a starting point is that they in a sense 
>  it expire then the other way where are they.
> James Chartrand:  Dated letters and so--.
> James Chartrand:  Are no longer useful after a given day so 
>  exactly the same way the paper letter would have you know become 
>  dated at some point it would be very nice to be able to revoke 
>  them and at some point I mean once we have a relocation system in 
>  place we would do that and I think at that point it would just 
>  work like any other room relocation system for credentials.
> Kerri Lemoie:  I feel before you go I'm sorry I'm going to call 
>  and I yes I'm going to ask you a short answer question what was 
>  the acceptance level of administration.
> James Chartrand:  It probably depends with part of the 
>  administration the registrar has been incredibly supportive and 
>  as I said before is very very forward-thinking I don't know that 
>  at other universities registrar's would look at it quite the same 
>  way however generally we found that whenever we've shown this to 
>  anybody within the administration you know they pretty quickly.
> James Chartrand:   We see the benefits of it.
> James Chartrand:  And the fact that it's extremely easy to use 
>  you get instant verification so I would say it's almost it's 
>  almost always the case that we get very very positive feedback 
>  from everybody within Administration and I suppose another way of 
>  looking at it is they've continued to fund this so that's a 
>  pretty good indication that people can see the value of it.
> Kerri Lemoie:  Yeah totally alright Phil on you have the floor.
> Phil_L_(P1): Yeah apologies can you hear me.
> Phil_L_(P1): Okay I was curious that you mentioned that you did 
>  internally decided that the need to use sort of existing 
>  processes and systems which were PDF depend if you will lead you 
>  at this stage to focus on encompassing the verifiable credential 
>  as an attachment to the PDF through the QR code but I was 
>  wondering is.
> Phil_L_(P1): And some sense looking at the rendering of the data 
>  in a Json file into something that could be more approximating a 
>  fully rendered text document of the sort to PDFs generate as a 
>  second phase so that you didn't have to deal with that particular 
>  problem that I suspect Dimitri's going to be talking about in 
>  later in the session or was there some other reason beyond that 
>  other than the not wanting to have to.
> Phil_L_(P1):  Icon building a renderer that could make it look 
>  pretty for.
> James Chartrand:  Yes so initially we thought that we would send 
>  these credentials down into our what a digital wallet you know on 
>  somebody's phone and then from there they would share it and you 
>  know possibly even at that point PDF could be automatically 
>  generated from the wallet directly but.
> James Chartrand:  Talking to the registrar's office they made it 
>  pretty clear that students expect at the moment a PDF and that's 
>  almost always how they use this thing and so kind of introducing 
>  a wallet into it just overcomplicate it they basically just need 
>  to go to this website Download a pdf and then use the PDF if it 
>  went into a wallet and then they had to do something from the 
>  wallet then they'd have to install the wallet app today.
> James Chartrand:   Deal with what was in the wallet so.
> James Chartrand:  Only just that for this pilot it's what made 
>  the most sense I don't know if that answers your question.
> <deb_everhart> but isn't the wallet the way the person controls 
>  the record?
> James Chartrand:  Yes yes exactly.
> Phil_L_(P1): No it does it I think that you're making a very 
>  Salient point that there's only so much transition you can make 
>  in one jump and at and the bigger problem isn't the technology so 
>  in so much as it is the humans that need to be able to feel 
>  comfortable with it so I think that's a very good observation 
>  thank you.
> James Chartrand:  Yeah and it was also very very easy well it was 
>  relatively easy to do what we did you know the amazing libraries 
>  that digital bizarre provides and they you know the amazing all 
>  of the amazing libraries that are in mpm just made it pretty easy 
>  to put this thing together and produce something that's actually 
>  is immediately usable.
> Phil_L_(P1): Got it understood.
> 
> Topic: Credential Display in Wallets Discussion
> 
> Dmitri Zagidulin:  Thanks so I wanted to respond to Phil's 
>  question real quick and then touch on the two points that Marty 
>  brought up in terms of your question Phil.
> Dmitri Zagidulin:  And why the approach of the PDF rather than 
>  being able to embed the display logic in the VC we need both we 
>  definitely need both will be talking about the display logic part 
>  are shortly but I wanted to highlight that one very important 
>  point.
> Dmitri Zagidulin:  In a way.
> Dmitri Zagidulin:  Producing a PDF or rather binding.
> Dmitri Zagidulin:  From a PDF to a credential shortcuts the need 
>  for a widely deployed verifier architecture and widely deployed 
>  wallet and display architecture because everybody from students 
>  too.
> Dmitri Zagidulin:  Admission counselors to border guards knows 
>  what to do with either PDFs or paper.
> Dmitri Zagidulin:  A binding from PDF to credential your you 
>  doing sort of progressive layering your you bootstrapping the 
>  whole ecosystem oh Natasha real quick on the two points that 
>  Marty brought up which is about revocation and about versioning.
> Dmitri Zagidulin:  Put lipstick revocation first one thing that I 
>  want to highlight is and James touched on this already.
> Dmitri Zagidulin:  Separation is an alternative mechanism to 
>  versioning so Ian a couple of use cases such as when you have a 
>  printed piece of paper or a generated PDF with the student hens 
>  over.
> Dmitri Zagidulin:  There's no way to do revocation there or if 
>  there is it's very crude like putting a footer down down at the 
>  bottom that says before accepting this please pick up the phone 
>  and call this admission officer to make sure that's still valid 
>  right that's that has both privacy implications and is incredibly 
>  awkward usability wise so what what that project does is use 
>  expiration.
> Dmitri Zagidulin:  As a risk mitigation mechanism.
> Dmitri Zagidulin:  Same way that replication is used so just 
>  wanted to highlight in those cases where you can't do revocation 
>  the forget that exploration plays the same.
> <kerri_lemoie> I've been working on an LER interoperablity 
>  spectrum that is open for input/opinions: 
>  https://docs.google.com/document/d/1fwMNbrFL78bVWnZ0BmObFBJnj0uGnFHhR00frybUiTA/edit
> Dmitri Zagidulin:  Same method the other thing that I wanted to 
>  talk John or a rather ask a clarifying question about is 
>  versioning can you tell us a little more what are what do you 
>  mean by versioning of of credentials what are some use cases 
>  where you would immersion it thanks.
> Marty Reed:  That a question for me.
> Dmitri Zagidulin:  Yes if you don't mind.
> Marty Reed:  Oh yeah sure so well at least in the open credential 
>  publisher project we have the idea that transcripts can be issued 
>  as verifiable credentials to a student however they may change 
>  until the official transcript is released and so we're just 
>  thinking about you know versioning.
> Marty Reed:   As far.
> <john_kuo> Wouldn't that be more of a lineage of revocation and 
>  re-issuance?
> Marty Reed:  You know as that transcript is updated do we need to 
>  replace the existing credential in the wallet do we need to call 
>  home and and check for a new version of that credential so into 
>  your to your expiration point you know that is one one thing that 
>  we've definitely you know looked at.
> Marty Reed:  From a from a verification standpoint but that's 
>  that's the use cases like the the transcript may be issued to a 
>  wallet prior to its being quote unquote official and so in that 
>  case you know the desired functionality would be that you know a 
>  student would go in look at their credential and it would say hey 
>  there's a new version of your credential would you like to 
>  download that now.
> Marty Reed:   And also.
> <dmitri_zagidulin> @John - revocation (of previous versions) 
>  might not be needed or appropriate. Because each VC says "at this 
>  point in time the following is true"
> <dmitri_zagidulin> revoking such a VC says "actually, that VC 
>  WASN'T valid at that point in time"
> Marty Reed:  For like a teacher teacher license a teacher could 
>  have a license with multiple endorsements attached to it that 
>  license can be updated over time to add and subtract endorsements 
>  and so for professional licenses there's this idea of you know 
>  versioning and updating endorsements within the existing 
>  credential.
> Dmitri Zagidulin:  Got it I think if I can jump the queue real 
>  quick so that makes a lot of sense and this sounds like a great 
>  topic for a future call the particular question of versioning of 
>  long-run credentials such as a medical history employment record 
>  or transcript sounds like there's a lot that we want to discuss 
>  their.
> Dmitri Zagidulin:   I do want to touch on.
> Dmitri Zagidulin:  Something that was brought up a question by 
>  John and Chad of would you be able to implement versioning as a 
>  series of revocation and reissuance and as I pointed out in chat 
>  that.
> Dmitri Zagidulin:  Visions yes revocation might not be required 
>  or even even allowed there because essentially each one of those 
>  success of their fiber credentials are snapshots of something 
>  that is true at that point in time so much by the way our paper 
>  existing paper credentials already have this notion of versioning 
>  intuitively such as a bank statement that says this is what we 
>  know to be true as of this point in time.
> Dmitri Zagidulin:   And then later if.
> Dmitri Zagidulin:  If another transaction comes in or if the bank 
>  changes something.
> Dmitri Zagidulin:  The bank statement looks different but at that 
>  point in time that was the views similarly what we're saying with 
>  the transcript is at this point in time this was the snapshot and 
>  by revoking such a verifiable credential we're essentially saying 
>  no that wasn't true of that time right revocation doesn't mean 
>  there is a newer version available it means whatever was said 
>  then is not true thanks.
> Kerri Lemoie:  Thank you Phil you have the floor.
> Phil_L_(P1): Thank you I didn't that I think Dimitri is what I 
>  was asked about in the versioning system that Marty was 
>  describing which is if let's say that a new version is available 
>  when the individual opens their wallet to look at a particular 
>  credential presumably the credential the wallet has been has been 
>  informed that there is a new version available to prompt them to 
>  do that if the individual.
> Phil_L_(P1):  chose not to I'm.
> <marty_reed> On the revocation discussion, I'd love to hear/see 
>  any demonstrations of revocation.
> Dmitri Zagidulin:  Wicked can you ask that again about the Third.
> <marty_reed> currently validation fails if there is a new version 
>  in the parent system
> Phil_L_(P1): Assuming that you would you're saying that the 
>  validation would fail when if they decided to send it to a third 
>  party and I just wanted to verify that that's what the intent in 
>  the current thinking would be and I guess sure yes that you know 
>  the way in which the question was posed to the person holding the 
>  wall at the holder is that there's a new version the credential 
>  available.
> Phil_L_(P1):  I presume you.
> Phil_L_(P1): Declined to accept that and just send the existing 
>  one you have because it is signed and the like the question is is 
>  the presumption that the verifier knows the new exhibit new 
>  version is available somehow and therefore would decline 
>  verification of the one that was sent to a an employer or some 
>  other entity and they then chose to verify try to verify that 
>  one.
> Kerri Lemoie:  Feels bad I'm question who is that question 
>  directed Up.
> Phil_L_(P1): Well it to put to full 12 Marty because he talked 
>  about it in the ocp but I'm also interested in McMaster case 
>  because it sounds like the way it's currently designed the coming 
>  back to the Mother Ship so to speak as part of the current 
>  designs of the system which would potentially allow them to be 
>  able to decline a credential that's been updated and the 
>  individual has failed to download the newest version so I just 
>  want to verify that too.
> Kerri Lemoie:  Okay to be introduced by and holding in the queue 
>  for one moment so James and Marty could reply.
> Dmitri Zagidulin:  Not at all sure though I do want to reply to 
>  that as well.
> Kerri Lemoie:  Okay great tips.
> James Chartrand:  Um so this is actually something that we've 
>  talked about a lot of Ink Master in the context the context of 
>  transcripts which is something that we would like to issue this 
>  way but my suspicion is that different registrars will have 
>  different policies and some might be fine with the kind of the 
>  snapshot in time and having a whole load of those circulating 
>  around and it's up to whoever's you know verifying the transcript 
>  to make sure they've got the latest and greatest.
> James Chartrand:   You know as they would.
> James Chartrand:  Copies before but I suspect in some cases the 
>  registrar would like to have more control over that and make sure 
>  that people are getting the latest copy fill you asked if at 
>  McMaster we might exert some control at verification time over 
>  what's available what's you know considered the latest and 
>  greatest and I mean we're not anywhere near there this is the 
>  pilot that I showed is pretty much what we've got for this.
> James Chartrand:   So we.
> James Chartrand:  Have anything beyond that however my guess is 
>  that at McMaster.
> James Chartrand:  They would want to indicate in some way that a 
>  newer version was available so you know so which is another way 
>  that it could work is simply that when you come to verify a check 
>  is made against a relocation list which might also show not just 
>  that something had been you know there might be different levels 
>  of relocation or different types of relocations so.
> James Chartrand:   You know as Dimitri said you.
> James Chartrand:  Means that the credential is no longer valid 
>  but you could imagine having a different type that's Ed's the 
>  credential is old and there's a newer version so that's a 
>  possibility and that I also wanted to just say quickly that yes 
>  the verification does come back to McMaster at the moment but 
>  only in the sense that you load the web page the actual 
>  verification is happening entirely within the web browser within 
>  the JavaScript so there's no phone home going on there.
> James Chartrand:  We could so any kind of you know check on the 
>  validity of a transcript would have to check a re vocation or 
>  status list of some sort hopefully that answers your question.
> Kerri Lemoie:  Thanks James Marty.
> Marty Reed:  So I kind of have a layered answer one is that in 
>  the simplest form that verification fails if the issuer decides 
>  that that credential is no longer valid so it's a call home to 
>  the publishing service that that request that verification now I 
>  will say publishing to Sovereign base wallet.
> Marty Reed:  Lisa the VC.
> Marty Reed:  It's you know again not elegant I'm not known for 
>  Elegance but the VC that is issued to the wallet is verifiable 
>  and then the payload itself must be verified to the issuer as 
>  it's basically a self-published or self issued VC at that point 
>  so there's there's two layers to the approach but we're exploring 
>  different different methods but that's how it works right now.
> <deb_everhart> don't registrars already submit "in progress" 
>  student data, such as NSC PDP data reporting and current 
>  enrollment requests from students and others, such as the 
>  enrollment letter shown?
> Kerri Lemoie:  Thanks Marty Dimitri you have the floor.
> <deb_everhart> I thought in progress reporting was a common use 
>  case
> Dmitri Zagidulin:  Thanks so I wanted to add to the discussion 
>  that so one I think versioning is a really useful mechanism we 
>  should an issue on it on the PC you do you repo and discuss it 
>  continue the discussion in depth on a future call I just want to 
>  say we already use something like this.
> Dmitri Zagidulin:  SeaWorld but in the w3c spec World each draft 
>  of the spec says here's the snapshot as of this date but go check 
>  over here here's the canonical location of the spec please check 
>  to see if it's it's been updated so it might make sense for us to 
>  explicitly able to specify this is a version where fiber 
>  credential and this is not a version where fiber credential the 
>  example of non version verify.
> Dmitri Zagidulin:   Credentials for example.
> Dmitri Zagidulin:  Here's an age verification credential that 
>  somebody is over 21.
> Dmitri Zagidulin:  That statement is never going to change the 
>  thing that can change is that it could be revoked.
> Dmitri Zagidulin:  They used fake ID or whatever however there's 
>  no there's not going to be an updated version like they're always 
>  going to be over 21 until they die is ETC but that's a different 
>  problem so let's open an issue this might be a really useful item 
>  for this group to work on.
> Kerri Lemoie:  Yeah I agree let's definitely do that does anyone 
>  else have any other questions for James or James you have 
>  anything else you'd like to add.
> James Chartrand:  No I think I'll take a look at this time so I'm 
>  good thanks thank you very much for having me.
> <phil_l_(p1)> Thank you James. Great work!
> Kerri Lemoie:  Now we appreciate it we appreciate it thank you 
>  very much doing chairman and hand things over to you so you can 
>  talk to us more about the while it display just continue on that 
>  discussion.
> Dmitri Zagidulin:  Thanks Kerri okay so let's look at thank you 
>  again very much James and let's look at late logic short of it 
>  is.
> <deb_everhart> thank you James!
> Kerri Lemoie: +1 Great work!
> Dmitri Zagidulin:  Pretty much all the while the projects are up 
>  against this this use case this need we need to be able to 
>  specify how to display the credential either HUD specify to the 
>  pixel or give some suggestions.
> Dmitri Zagidulin: https://github.com/w3c-ccg/vc-ed/issues/16
> Dmitri Zagidulin:  So this is perfect group to make a 
>  recommendation test it out and then make a proposal to Upstream 
>  to the ccg and to the verifiable credential working group so I'm 
>  going to have issued number 16 on our repo talking about this I 
>  add a couple of notes of use cases.
> Dmitri Zagidulin:  And so I'd like to ask people disease did he 
>  sound reasonable are there.
> Dmitri Zagidulin:  Either use cases to this display specifying 
>  the display logic that we should add and then we can propose a 
>  mechanism in the next calls and get dry so essentially.
> Dmitri Zagidulin:  I was not able to pull up the credentials the 
>  GitHub issue.
> Dmitri Zagidulin:  We need to specify or advise.
> Dmitri Zagidulin:  Any sort of VC consuming software how to 
>  display that VC.
> Dmitri Zagidulin:  We need to support both cases.
> Dmitri Zagidulin:  Display logic is completely embedded in the 
>  credential or.
> Dmitri Zagidulin:  Display logical if somewhere else so you we're 
>  linking to an image file or an SVG file or an HTML template 
>  somewhere else and we just linking to it from the credential so 
>  that when it comes time to display it display software go use 
>  that template.
> Dmitri Zagidulin:  Obviously when we're embedding the display its 
>  Integrity texted by the verifiable credential signature itself.
> Dmitri Zagidulin:  Always we're using linking we definitely want 
>  to recommend using a digest hash like the anchored resource 
>  mechanism.
> Dmitri Zagidulin:  We probably should be able to specify the 
>  content type of the logic but this link or this embedded logic is 
>  PDF and HTML and so on.
> <phil_l_(p1)> The anchored resource mechanism has greater 
>  applicability to other cases where the size of the "thing" is too 
>  big to be included within the credential itself.
> Dmitri Zagidulin:  And we should talk about the preference of the 
>  credential display being cross-platform right if we're going to 
>  we're going to have a template if we're going to have an image 
>  you'd be great if we could just specify one and it would work 
>  across all platforms mobile desktop and so on but is anybody who 
>  works in web design knows that is an almost on achievable dream 
>  so given that as a second step we should provide mechanisms.
> Dmitri Zagidulin:   That say okay if you're using this.
> Dmitri Zagidulin:  Of device use this Logic for using a much more 
>  constrained device or a much bigger screen then use this logic 
>  fortunately we have prior art for both images and stylesheets in 
>  general so lot of HTML world has the technology that says if 
>  you're viewing this page on a mobile phone display this way to 
>  using it on desktop display this way if you printing it then use 
>  this way so we should we should be mindful of that.
> Dmitri Zagidulin:   Let's see we got six minutes.
> Dmitri Zagidulin:  Love to hear from from the group are there 
>  other considerations are there other input requirements for this 
>  item.
> Dmitri Zagidulin:  Keith go ahead.
> Keith: I think maybe I can just dig deeper on display because I 
>  think that there can be differences in how well it's display 
>  information like what's it take Atticus talk about what kind of 
>  information like typically I mean other while it's that I've been 
>  involved in you just say things like issue or info like contact 
>  support info and then the contents of the VC itself and maybe 
>  images so like I've often thought that while it vendors can 
>  independently choose how to show that information but I do I mean 
>  I totally agree with you.
> Keith:  a point that when you want to display things like issuer 
>  logo.
> Keith: This PDF image then you need ways that wallets you know 
>  you don't want to get a crop properly you want to be able to get 
>  it sized properly as you can display it properly is that what you 
>  mean by this because is that what you mean by display a my 
>  capturing it correctly or are you mean other things as well.
> Dmitri Zagidulin:  Yes yes no that's it and you're absolutely 
>  right that it should be optional.
> Keith: And I just like it's up to wallet that I mean that's kind 
>  of the beauty of the market is that the the wallet with the best 
>  presentation kind of will you know be preferred be preferred by 
>  consumers is that rather than some sort of like trying to do 
>  static what is it often like display will be one of the key areas 
>  of differentiation between wallets how well they do display.
> Dmitri Zagidulin:  So you're absolutely right though I do want to 
>  say that they're still in need to be able to do this optionally 
>  as well James go ahead Joe.
> James Chartrand:  Yeah so I mean just one of those needs to do it 
>  statically is as I mentioned before one of the things we'd like 
>  to do at McMaster is how the student basically.
> James Chartrand:  Create the plastic student card inside a wallet 
>  and we want to try to make it initially you know as kind of a 
>  progressive introduction of this to make it backwards compatible 
>  and so therefore we want to include the barcode that's on the 
>  plastic student card and possibly also a QR code that somebody 
>  could use to similarly scan their student ID so you know it's 
>  unlikely that a wallet will know how to.
> James Chartrand:   A show those kinds of things or even know to 
>  show.
> James Chartrand:  So if we could instead just provide a single 
>  image that's shown in the wallet or a student card or for a 
>  student ID it could be pre you know pretty constructed with the 
>  barcode down at the bottom with the student image on it with the 
>  logo of the University so basically again recreating the pretty 
>  much the same image image that's printed on the plastic card.
> Dmitri Zagidulin:  Thanks James you've got a couple minutes left 
>  Andy go ahead.
> <kaliya> QR codes that are static with VC s dangerous
> Andy Miller:  I was wondering your thoughts about the use case of 
>  where the VC is actually embedded in the image or PDF that's 
>  centrally how open badges that's it now I'm baked badges is a PNG 
>  or SVG that has the credential in baked into it using the 
>  structured data.
> Dmitri Zagidulin:  Great question that that should not should be 
>  another item of discussion Phil go ahead.
> Phil_L_(P1): Yes I guess what I wanted to say that it seems to me 
>  that the hash link approach that you described is actually a 
>  broadly applicable to any kind of circumstance where the content 
>  of an object is bigger than is reasonable to include in the in 
>  the VC itself and so by you know focusing on how you would apply 
>  that to different circumstances such as the image on a card and 
>  what's presented when it's displayed.
> <kaliya> Very dangerous because the can be super easily copied 
>  and replyed
> Phil_L_(P1):  then is the composite of the polled image from 
>  wherever the Third.
> <dmitri_zagidulin> @Kaliya - great point
> <dmitri_zagidulin> which suggests the need for templating (rather 
>  than static image)
> Phil_L_(P1): And the rendering of the thing of the way it's done 
>  traditionally on the plastic would be indistinguishable from the 
>  plastic itself so I think that's the probably the most productive 
>  approach and the one I would urge us to consider the biggest 
>  problem that that and UND just described is the the same problem 
>  of payload size you can do that for small DC's but you can't do 
>  it for VCS that contain much like evidence and things like that.
> Phil_L_(P1):  that thanks.
> Dmitri Zagidulin:  Thank you two minutees left James go ahead.
> James Chartrand:  So just about the of the idea of using a hash 
>  link for I think there might be privacy concerns there so we 
>  might not want to have the student information so and in 
>  particular say their photo at a URL you know available add URL we 
>  would want to keep an entirely embedded within the credential the 
>  so that's just one concern possible concern.
> Dmitri Zagidulin:  Thanks James and Kalia.
> <phil_l_(p1)> are there privacy concerns there if the destination 
>  is itself encrypted?
> Kaliya: I'll just say what I said in chat stata QR codes.
> Kaliya: And I guess the same is true for barcodes but you know 
>  static QR codes with verifiable credentials within them that are 
>  signed are very very very dangerous the reason being is that they 
>  are entirely copyable and replayable.
> <phil_l_(p1)> Excellent point Kaliya
> Kaliya: Is this not true of verifiable presentations that are you 
>  can't copy and replace because their presentations not the 
>  original credential so I have an unfinished but readable paper 
>  about this largely written by John Jordan that I think I'll try 
>  and send a list I'm sick right now otherwise I'd send it to chat 
>  right now but.
> Dmitri Zagidulin: https://github.com/w3c-ccg/vc-ed/issues/16
> <kerri_lemoie> Thank you!
> Dmitri Zagidulin:  Thank you so much Kelly and we hope you feel 
>  better soon alright so everyone please let's continue the 
>  discussion on issue 16.
> Dmitri Zagidulin:  And a quick questions before we adjourn go 
>  ahead.
> Dmitri Zagidulin:  Thank you everyone.
> Kerri Lemoie:  It sounds good nope I would just say and that's 
>  good that's take a look at that issue and keep it going we can 
>  revisit this in the near future thank you so much James and 
>  Dimitri appreciate it all thank you.
> <phil_l_(p1)> Thanks!
> 
>