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0xBeefFed

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Paranoid.

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This is interesting, and is reflected in some other comments, but I have always gone under the assumption that you will only learn things once so it is best to learn them the correct way. This mostly holds true in an academic situation though in my experience, and I have applied it as such.

I guess now is the time to look into how to root the console and install a custom ROM in a similar fashion to de-Googling your android phone. There is already enough support in the community for side-loading APKs and the like. Does anyone know of any ways to achieve this?

Bit late to the party. I checked out thebrowser.com but there is no mention of the subscription cost anywhere - it seems they won't tell you until you give them your email. Would you know the cost per billing period? It seems like a cool service but I'm curious how their cost compares to something like the economist (different information, I know).

If a user is in close confinement with someone they fear will lash out at them if they test positive, for one. Off the top of my head, lets say you take an Uber home and the driver now has your home address, you don't know if they will try and attack you.

This is an example off the top of my head, as other comments in this thread have explained, violence against people who have the virus is happening around the world and is something that must be accounted for in these protocols.

Edit: a link to a story from another comment (https://www.washingtonpost.com/world/the_americas/coronaviru...). I hope you can see that this technology can worsen this.

I appreciate you looking at the other side. To explain my view point, in this system it seems like all of the risk is put on the infected party who reports themselves. By decreasing the level of control they have, I believe you will see a decrease in the number of adoptions. It is valid to think about the non-infected user wanting to have this information, but today they don't even have this information so to even know they were exposed on their commute is above and beyond what is in place today.

I guess my original comment is a bit vague. When I look at these protocols I am interested in how large scale adversaries (Nation State) would use this technology, but also small scale adversaries (day-to-day person you are not friendly with). I think its also important to note as others have, that being outed as having the virus does put people at risk of violence in some places.

The protocol states that it will upload the Diagnosis Keys, a set of Daily Tracing Keys relevant to your exposure. So in short, if this is the case it forces the user to either upload all their keys or none.

I would like to note that a v1.1 has recently been released, my information is about v1.0.

I think its important to give the power to the people by allowing them to omit tokens from sensitive time points. In the current protocol, that means losing a whole days worth of contacts. If you reduce the period to an hour, you still allow people to share the contacts made on their commute or their lunch break without divulging or tracing them back to more sensitive time periods they don't want to be traced back to.

So all of the tokens are being put on a central server. Today, governments use WiFi and Bluetooth to track traffic. It is not far fetched to see that your commute from point A to B could be tracked using Bluetooth receivers in transit stations.

This technology is currently being used to track people today. The use of Bluetooth address randomization does not do a sufficient job to prevent this, the only option is to not use Bluetooth.

It is important that people are aware of these risks. I am fortunate to live in a place where I can live my life without scrutiny from the government, but not all are afforded such a luxury.

The difference is that the old system relied on human memory which is fallible, not to mention you can omit details which would lead to further trouble (infidelities for one). In this system the only control a user has is to turn off bluetooth, or leave their phone at home if Apple/Google override the users ability to turn this off.

The unlinked DP-3T is one extreme, there is a happy medium if developers don't want to use Cuckoo Filters or Bloom Filters due to false positives, which is to decrease the linkable period. If the period was an hour, people could freely share legitimate tokens for their commute, but hide the ones where they had an hour long 1-1 with their manager.

It should be noted that your privacy is not preserved if you test positive and need to upload your Daily Tracing Keys to a server. Your broadcast IDs for an entire day can be linked together, making it easier to de-anonymize you. I understand that they use Daily Tracing Keys to reduce the demand of the backend server, but I think it would be better for user privacy if they either reduced the linkable period from a day to say an hour, or used an unlinkable design.

There are some differences. DP-3T proposes two different systems, one with linkable tokens and the other without linkable tokens. The first system is similar to Apple-Google in the sense that your tokens for a day are derived from a key which is uploaded to a central distribution server when you test positive. In the second system the tokens are not linkable and they propose the use of a Cuckoo Filter to reduce the space complexity. A Cuckoo Filter is a probabilistic data structure that can tell you if an item is not or might be in a set. As a result there are some false positives.

DP-3T also explains how records are uploaded to a central server and the interactions with health-care providers. Apple-Google omit this part and focus on proximity data collection.

Edit: Formatting + I wrote a survey paper on a few of the distributed protocols and how they defend against linkage attacks (de-anonymization): https://github.com/robertTheHub/ContactTracingSurvey/blob/ma...

The data on comorbidities seems to match data from Italy, where hypertension, type-2 diabetes, and heart disease, were the top three in that study [1].

One thing I do wonders is if the mortality rate is higher as they counted the number of patients requiring intubation, not those who received it [2].

[1] https://www.epicentro.iss.it/en/coronavirus/bollettino/Repor... [2] https://jamanetwork.com/journals/jama/fullarticle/2765184?gu...

I am not sure if this relates, but this past year at Blackhat there was a talk on Messaging Layer Security and they broughtup a concept called TreeKEM, where users share keys in a tree heirachy to reduce the number of shared secrets.

Again, not sure if this is applicable, but the comments made me think of this.

[0] https://www.blackhat.com/us-19/briefings/schedule/index.html... [1] https://i.blackhat.com/USA-19/Wednesday/us-19-Robert-Messagi...

Your use of the word partial could lead to confusion. The Diagnosis Keys are a subset of the Daily Tracing Keys for the days youre contagious. You then upload these Daily Tracing Keys and associated day numbers. Also you are incorrect about the involvement of a timestamp. The protocol uses DayNumbers to track the specific day a Daily Tracing Number was used.

In terms of privacy, small-scale adversaries can deanonymize infected users that have uploaded their [keys by keeping logs] of and limiting who they have come in close contact with.

On a large-scale, adversaries in control of large Bluetooth receiver networks (such as cities performing traffic analysis) can now track the movements of individual infected users over the course of a day. One could argue that this is already being done to track anyone with bluetooth enabled.

In addition, the process of uploading to the backend server could alert adversaries monitoring your network that you (the device using your IP address, uploading to the server IP address) have tested positive for the virus.

I recommend that you look at other contact tracing protocols that circumvent some of these issues by decrease or eliminating the linkability of identifiers, allowing users to censor records uploaded, and encourge the use of network-anonymization.

*Edit Spelling - Source: https://covid19-static.cdn-apple.com/applications/covid19/cu...