BlockTrace

Story

There is not a mainstream privacy preserving based contact tracing app.

We think that such a project would be vital for colleges to reopen in the fall.

Google and apple have shown interest, but their solution does not appear to be privacy preserving.

Technology

We used a block chain to be able to store the data decentralized, while also preventing the spoofing of any interactions. This was written in c++.

We build a front end demo in Android studio which would be the user facing app, which would would track interactions without interupting privacy, allow the user to check if they interacted with anyone who has been diagnosed with Covid19 without knowing who they are specifically, and allow the user to mark that have been diagnosed to warn others.

How does it work?

The privacy preserving idea comes from that you send out randomized strings to phones that are within 6 feet of you and you keep track of all strings that you have ever sent. Then if you have Covid19 you will upload all of your sent out strings from the past 2 weeks into an "infected" string database. Users can also check their list of people they have interacted with against the list of infected people in order to determine if they have interacted with anyone (this would be automatically done by the app)

This would allow determining interactions without compromising the privacy and even the location of a specific user.

Block chain allows for a prevention of spoofing as well as keeping the data in many different places, while making sure that it is perfectly up to date.

What have we done so far?

We have created several different aspects We created the frontend using android studio, as well as the blockchain is built in c++.

Next Steps

With some more time we plan to integrate these different pieces together, Move the blockchain into being fully distributed, and pitch to universities as an important and smaller scale starting point for an app like this.

Built With

• c++
• cryptopp
• http
• sha256