Tokyo (SCCIJ) – The Swiss coronavirus “PT-App” to trace Covid-19 infections through smartphones will be broadly available from June. PT stands for “proximity tracing”. The first version may be published already this week. It will be free and its use voluntary. Work on such software is underway also in Japan. But the Swiss technology sets high standards.
Testing the DP3T app at EPFL (© 2020 Jamani Caillet)
Swiss-led European effort
The Swiss Federal Institutes of Technology in Lausanne (EPFL) and in Zurich (ETHZ) led the European DP-3T consortium for the app development. DP-3T is the abbreviation of “Decentralized Privacy-Preserving Proximity Tracing”. Other members are Catholic University Leuven, Delft University of Technology, University College London, Helmholtz Centre for Information Security, University of Torino, and ISI Foundation. The consortium also worked out the organizational and legal foundations required for secure operation in compliance with data protection regulations. The ultimate responsibility lies with the state.
And this is how the app works: the smartphone uses its Bluetooth connection to analyze contacts with other smartphones, and all contacts with a distance of fewer than two meters and a duration of more than 15 minutes are stored on both devices. If one of the stored contacts becomes infected and this information is put into the app, a warning message is automatically sent to all other smartphones with this contact. Such contacts could then also be tested and isolated for safety’s sake. After long discussions about the storage of personal data, data protection experts now attest to the app a high level of security.
Transnational solution
From a scientific and technical point of view, the open-source DP-3T protocol is an international pioneer. Several countries have announced their intention to launch an app based on it. Apple was also inspired by the “Swiss solution”, which provides for decentralized data storage. The Apple engineers in Cupertino had been contacted early on by the IT expert Edouard Bugnion of DP-3T from French-speaking Switzerland, the Swiss info magazine Watson.ch reported. The co-founder of the IT company VMware asked them to find a solution to a problem that was hindering the development and launch of Bluetooth-based proximity tracing apps.
The DP-3T team is working with developers and designers from Germany, Estonia, Finland, Italy, Austria, and Portugal. The aim is to achieve cross-national functionality of each national corona warning app in Europe and beyond. “We have no claim that our solution will become a global solution. But we are in contact with researchers around the world”, said Marcel Salathé, a member of the DP-3T consortium.
Tests with the Swiss army
Over the past weeks, EPFL computer scientists have been testing and refining the smartphone-based system developed by DP3T, with the help of 100 members of the Swiss Army. Their goal: to optimize the app’s ability to alert users after they’ve been in contact with someone contagious with COVID-19 while building trust around the open system.
The true reality tests will come after the launch of the app, though first, enough people need to download and install it. The more people use the app, the more useful it becomes. Second, the data of an infected user need to be put into the application. With such comparatively high hurdles, even the Swiss PT-App may not become the versatile “Swiss army knife” to combat the spread of the coronavirus. Other measures beyond the app also need to be applied.
Text: Martin Fritz for SCCIJ
