Cwa-wishlist: anonymous registration at restaurants, hairdressers etc. using CWA

[hackedal]

Problem and motivation

At the moment there are a lot of negative news in the media about the issue, that personal registration data, which has to be left when visiting restaurants, hairdressers etc. has been abused for example by the police. People are afraid of fraud, tending to leave fake contact data, which makes contact tracing impossible in case of an infection.

Feature description

It would be great, if CWA could generate (bypassing the contact tracing API) a "manual" random key, maybe 12 oder 16 characters long, that is presented for a limited amount of time (5 minutes should be enough) on the display of the device. This key can now be written on the restaurant owners guest list. After the key disappeared from the display, it is stored for 14 days locally in my device. In case of an infection, the restaurant owner will send his list to the health authorities, who will inform the people on the list. If there are non-CWA-guests, who left their contact data, they have to do it manually but if a CWA-user has left his generated key, it will be added to the central database and fetched by all the CWA-users and the restaurant visitor will be warned, because his device matched it's own generated key.

This feature would have a lot of advantages:

• full privacy for CWA-users: neither the restaurant owner nor the police will ever know, who was in the restaurant
• a warning for CWA-users, even when non-CWA-users were in the same restaurant
• more CWA-users, because only CWA-users will have the advantage of staying anonymous

I hope you like my idea!

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Internal Tracking ID: EXPOSUREAPP-2034

[daimpi]

Related:

• #59
• #70
• #77

[chr-chr]

Hello,

I've come up the same idea but in a different way.

To my understanding the Corona-App is bound to an user.

Having the App working/registered as a location on a device provided by owners,
they would get an active guest list.

The Visitor can actively or automatic login and out having full privacy.
Owners can prove their countermeasures.

Regarding the police interests the CWA might help as well:
Actually a backtrace gets done on a positive corona test.
How about giving the police a way to issue a call for witnesses in an anonymous way?

[Ein-Tim]

How about giving the police a way to issue a call for witnesses in an anonymous way?

I don't think thats a good idea (neither do I think the public would appreciate that).
The CWA should just be used to inform the user if they had contact with an Covid-19 sick person.

Edit:
This is also not allowed by Apple (https://developer.apple.com/contact/request/download/Exposure_Notification_Addendum.pdf):

[DirkReu]

In #140 I described a little different approach. Both variants avoid having a open tracking of the user's daily life. It would be worth weighing advantages and cost of both ways.
I close #140 to keep the number of requests small.

[cutec-chris]

An additional positive effect of this feature is, that more users would use cwa cause this feature makes it a lot easyer to "check in" in restaurants,cinemas and so on.

Additional to the ops idea, the restaurants could have an own app that can scan the code and store it. Maybe those app could additionally "scan" (fotograph) the paper formular of non-cwa users and encrypt it and send all together to the Gesundheitsamt if needed. That would also protect non-cwa users from authorities accessing the paper-registrations. Cause the restaurant yould destroy the paper registrations daily after the app has scanned and encrypted it.

Also the additional app could keep track of deleting the encrypted daily files after 14 days.

[mf179]

I like hackedal´s idea. And that it should be enhanced by scanning the code by an App/phone of the restaurant as proposed by cutec-chris.

So the basic functionality would be the same as of today, just that the BT transmission is replaced by code scanning:

• visitor requests CWA to generate a code that is then displayed as QR-code on his phone, visitor´s CWA keeps the code for 14 days
• restaurant´s CWA scans the code, verifies authenticity as a CWA code (to avoid faked QR-codes), confirms reception with some audio signal so that the responsible knows that obligation of registration is fulfilled, and restaurant´s phone/CWA keeps the received code for 14 days

Just the notification process differs as the feature implies a one-way-registration only. An infected visitor can therefore only warn the restaurant´s app (the usual way with sharing his code via server). And the restaurant app (that collected all visitors) needs then to notify the other affected visitors by sharing the related, stored visitors´ codes via the server. The visitors´s apps need to scan the shared codes for their own codes.

I would share Ein-Tim´s concern that everything that is additionally proposed may mainly delay or even hinder the adoption of the basic proposed feature.

It should be noted that while this feature may extend the reach of the CWA the user is still free to deactivate CWA´s BT-contact-tracing, if they don´t like it. Which may further help for adoption. And it works with all phones regardless whether those support the ENF.

[ferdinand]

Looks like the UK app has included a „Venue check-in“ feature.

I‘m pretty sure this feature would give the CWA a remarkable boost. Both, venue owners and guests, would love to use a privacy friendly check-in app instead of paper lists and shady third-party software.

[stbrit]

This would be a game changer. Everyone would get the app if they don't need to fill out paper registrations anymore. And people would be contacted via the app if needed quickly. Such a game changer. Britain managed to do it in their app surely we can as well. This needs to be an absolute priority.

[gittyhub2018]

I think this is a good idea. Another idea is, that the Corona App scan a QR Code in the Restaurants or something like else. This QR Code can be dynamic created at a screen in the restaurant or can printed every hour. This code have following information:

• Date and Time in UTC. (With this information the CWA can proof, that this code is not too old. UTC is Good for exchange from Time Information between Time zones).
• Public Key and cryptographic signing information, that the random key is allowed for CWA using (Spoofing Protection or Protection against illegal hacking from CWA. If you accept too long unsecured strings, you will be hacked if the CWA has a bug. The Public key, who created the restaurant owner can signed from a CWA Trusted Third Party, that this Public key is allowed to use with CWA. Or the Fingerprint must be printed on screen or paper with the QR Code and the CWA user must confirm that this is the Right Public key. The last idea is easier than the trusted third party idea. ).
• random key.
  The guests can scan this QR Code and if the guests must be warn, the random key in the QR Code will be transmitted over the CWA Servers. With a recreation of this QR code every hour you can tell all CWA Users who are effected. The QR Code have not to be changed so fast, because the code is only in the local app and the owner of the restaurant have not to transmit too much keys, after he or she will warn the users. This could be improve the performance, then you have not be transmit too much keys. Restaurants can change the key every hour e.g with a normal paper print (if the restaurants have not enough technology knowledge or similar things for a Screen.). The Date/Time Information is for CWA to local proof the validity of the QR Code. This can improve the acceptance by the owners.
  If the owner need a acknowledge from the CWA, this could be a Bluetooth beacon, who don’t own any personal information from the users. This acknowledgment must not be stored permanently! The MAC Adress or other informations could be have personal information.

This can improve the acceptance of CWA, solve the problem of personal information with guest lists and with a QR Code an owner can easy implement this in his own workflow. An QR Code is easy to create and make the contact tracing safe and easy (KISS-Principles).

Another idea, who is more complicated is to transmit Bluetooth keys in the owner stores. But the CWA must know that this is not a person for tracing. This is a random key for owners of the restaurant. The different is that the CWA does not try to catch the owners signal strength or try to exchange keys. This could have negative effects of battery lifetime and privacy. The QR Code function is easier and safer.

[daimpi]

I just recently saw someone on Twitter suggesting integration of their registration app into CWA to provide this functionality 🚀.

[cutec-chris]

Yeah a lot of people have this idea, and think its good. But noone of the Devs answers here. Maybe thers not enougth money left ;)

[spekulatiusmensch]

There is now a proposal called CrowdNotifier that seems to fit this issue. It would be interesting how it could be integrated into CWA. They actively ask for feedback and I think it should be discussed here as well.

[daimpi]

Linus Neumann also brings up the idea of "Decentralized Presence Tracing" on his blog (German): https://linus-neumann.de/2020/10/die-corona-warn-app-verliert-den-anschluss/

[rennertimo]

Linus Neumann also brings up the idea of "Decentralized Presence Tracing" on his blog (German): https://linus-neumann.de/2020/10/die-corona-warn-app-verliert-den-anschluss/

The proposal that Linux Neumann describes matches #140 .
I like the idea. Easy to implement, make use of existing assets, no additional overhead, same fast reporting in case of a positive test result

[jucktnich]

Just another idea for this topic.
At every table is an unique qr-code with this parts:
•ID of the restaurant, bar, ... registered at a cwa-server and validated by the local 'Gesundheitsamt' so the restaurant is real and not a scammer. On the cwa-server are also geo data connected to id, so the user can validate that he is really there (else someone could use the same qr code on different places. The validation could be made by the user (pin at a map, user checks if it's true) or automatically by the geo data of the device (please use in minimum the first possibility, else some conspiracy theoretical will says: 'oh the government will track us')
•the number of the table/area (optional)
This could be helpful, if you do have a really big restaurant, so only for example the radius of 50meters around the 'infected' table gets a warning.

The qr code is scanned when arriving and when leaving, the time stamps are stored in combination with the ID and table for fourteen days.
When someone is infected the ID of the restaurant (optional in combination (decided by the infected user) with the table IDs (the middle of all the tables is not the real, it's just on of for example five tables, so the person is further anonymous)) and the time stamps are put on the server and is distributed with the other IDs.

[digital-codes]

Can we integrate the https://platform.projecttogether.org/initiative/caMqKqhU8rffg1RMqSrMH3ukgPn1 from "wir vs virus" to get the "registration" functionality?

[MikeMcC399]

@digital-codes

Can we integrate the https://platform.projecttogether.org/initiative/caMqKqhU8rffg1RMqSrMH3ukgPn1 from "wir vs virus" to get the "registration" functionality?

The link which you mention leads to darfichrein.de

My understanding after looking at https://www.darfichrein.de/dir/home including https://www.darfichrein.de/dir/faq is that this solution is not anonymous. In fact after scanning the QR code on https://darfichrein.de/dir/do-it , the user is asked for their name.

So I don't think this could be tightly integrated into CWA, which is based on anonymity and lack of knowledge of physical location, which is fundamental to the GAEN (Google Apple Exposure Notification) Framework / System that CWA is using.

Also darfichrein.de stores data centrally, not on the user's smartphone, which makes it very different to the decentralized way that CWA is stored. It is difficult to image these two aspects coming together as well.

[cascremers]

There is now a proposal called CrowdNotifier that seems to fit this issue. It would be interesting how it could be integrated into CWA. They actively ask for feedback and I think it should be discussed here as well.

Many ideas above are similar, but for privacy and data protection reasons CISPA would support the decentralized CrowdNotifier approach mentioned already by @spekulatiusmensch .

[Thomas-Hendrik]

Hi, I wrote to the SAP-Team via corona-warn-app.[email protected] yesterday to emphasize the importance of such a functionality. As soon, as I am getting a response, I will write about it at this place.
How can we push it?
There is one thing I am missing in the features described: The App needs an Application in the backend that helps the Gesundheitsämter to analyse the infection spread patterns and automatically inform people.
How do they do it today? In reports I alway see people (e.g. soldiers) sorting paper and doing phone calls...

[gittyhub2018]

How do they do it today? In reports I alway see people (e.g. soldiers) sorting paper and doing phone calls...

The soldier or health staff doesn't get any information about the app. This is 'cause privacy protection. The high privacy level is the reason, why many people install it and in other countries this doesn't work. CWA should warn the people that they can inform the health office and ask for further information. The health office get their information from doctors and Analyse labs, who test against the virus. Is someone infected they give the address of all possible people to the health office. Only the health office can enforce a quarantine. And in most case, the contact tracing after an infection case is the paperwork.
But CWA should not tell the information automatically to the health office, because people can have privacy concerns and fight against the CWA using.
For digital contact tracing after infections should be a developed a WebApp, which can automatically connect the same person to a database. CWA should not do this.

I hope now is it more clearer.

[alanrick]

How do they do it today?

I use the Irish app. Under settings you can add your mobile number so that the tracing service can contact you directly if you want. It’s voluntary. There are over 1.3 million active app users (Ireland has a population of 4.4 million) so the evidence is that this voluntary field helps combat Covid but doesn’t deter users from downloading the app.

[Thomas-Hendrik]

The Irish App won´t be the mass solution for Germany, let's better push the CrowNotifier solution as an extension of the CWA: https://github.com/CrowdNotifier/documents

[derhingugger]

I like the idea to give the CWA a chance to contact me after I visit in a restaurant, cinema or shopping mall in case there was a positive tested person. It make the CWA stonger and more atraktive if this give me the chance to visit these kinds of places. Restaurants or Cinema can open for people they willing to leave these contacts by checking in and out.

[alanrick]

And here's the use-case with the Minister for Health (Jens Spahn) in the leading role 😉
https://www.apotheke-adhoc.de/nachrichten/detail/politik/trotz-corona-spahn-informierte-restaurant-nicht/

I suspect that's why he's keen on having the app display the date dangerous contacts took place, but I agree with you that adding this suggestion (#138) would be more effective and might have avoided the lockdown lite.

[Onophrio]

It is absolutely meaningful, not only to protect personal data from „lying around“ openly on paper in the restaurant, but also to ensure motivation of data security-concerned folks to actually use the corona app. Would be a push to download numbers.
If data is stored on federal servers (voluntarily allowed by app users), this would mean a huge relief of workload in health administration in tracking down infection chains. Even, if not everybody will use that feature. Every piece of paper the „Gesundheitsamt“ does not have to evaluate manually gives them more time to focus on the questionable cases (so it doesn’thave to be 100% accurate, semi-automated as stated in a previous post would already be a huge boost in efficiency)
In principle, this works, as Bavaria demonstrated by (again) going forward with pragmatic solutions:
https://www.bayern.de/neue-software-vereinfacht-corona-registrierung-bei-gaststaetten-gerlach-lobt-clevere-digitale-loesung/

This is bei. adopted by restaurant in other states, which ashames their state governments as well as federal government.
I would appreciate being able to deliver the full package of data to RKI, given they are stored there encrypted and only RKI and health authority can access it.
If marked clearly in the app with a toggle „Data plus“ or something, people would dinghaft deliberately and all data protection concerns are meaningless - and I bett people see the usefulness and they WILL use it.