Digital technology creates risks to people's privacy in ways that did not
exist before. I design end-to-end private systems to mitigate these real-world
privacy risks. In this talk I will discuss my designs for two applications.
These applications highlight key aspects of my work: I analyse security,
privacy, and deployment requirements; and address these requirements by
designing new cryptographic primitives and system architectures.
In the first part of this talk, I will focus on my DP-3T and CrowdNotifier
designs for digital proximity and presence tracing that help mitigate the
COVID-19 pandemic. These designs combine novel cryptographic primitives and
communication systems to protect users’ privacy. The DP3T and CrowdNotifier
designs have been deployed to millions of phones. In the second part of this
talk, I will present DatashareNetwork, a document search system for
investigative journalists that enables them to locate relevant documents for
their investigations. DatashareNetwork combines a novel multi-set private set
intersection primitive with anonymous communication and authentication systems
to create a decentralised and privacy-friendly document search system.