BlueTrace: A privacy-preserving protocol for community-driven contact tracing across borders
This April 2020 whitepaper authored by Bay et al. of Singapore’s Government Technology Agency presents BlueTrace, a privacy-preserving protocol that underpins Singapore’s nationally deployed Bluetooth-based contact tracing system TraceTogether. The white paper describes the purpose of BlueTrace as addressing the key limitation of manual contact tracing: “an infected person can only report contacts they are acquainted with and remember having met.” They describe the protocol’s design considerations and implementation challenges, as well as how it meets interoperability requirements of health authorities considering its use. Finally they address potential security concerns surrounding the tech. They conclude that while not a stand-alone solution to solving contract tracing issues during a pandemic, Bluetooth-based automated tracing instances can still “ultimately coexist and support the pandemic response plans and processes of the public health authorities guiding us through” a pandemic. The authors also make available OpenTrace, an open-source reference implementation of BlueTrace, on GitHub.