I am a Senior Lecturer at the University of Cambridge Computer Laboratory and a Teaching Fellow at Robinson College, Cambridge.

My research work examines the security and privacy of large-scale distributed computer systems. Within this broad area, I am currently interested in the security and privacy of networked mobile devices, such as smartphones, tablets and laptops. I examine the security of the devices themselves as well as the security and privacy problems induced by the interaction between mobile devices and cloud-based Internet services. I approach this through the critical evaluation of existing products, by designing and building novel prototype technologies, and by measuring human behaviour.

Research projects

  • Device Analyzer has collected statistical usage data from over 23,000 Android mobile devices across the world. Device Analyzer preprocesses data on the mobile device to remove direct personal identifiers and reduce the privacy risk of sharing the data with the university. If our study participants have agree, we share a subset of the data with over 40 partner research labs. We also use it ourselves for research, for example, by looking at the state of Android security.
  • Nigori is a distributed system for storing and synchronising application state between mobile devices using cloud storage. Nigori provides strong privacy guarantees, preventing the cloud provider and application developer from accessing any personal information.
  • The Isaac Physics Platform uses recently developments in web technology and computer-based educational techniques to improve physics teaching in English schools, working in partnership with teachers and educators.

Previous work includes:

  • Computing for the Future of the Planet explores how computers can help solve some of the world's most pressing problems arising from climate change and the need to build sustainable systems.
  • The TIME-EACM project, which explored how sensor networks and distributed systems can be used to improve traffic and transport in the 21st century.
  • The Cambridge Mobile Urban Sensing Project which measured and monitored air quality, particularly urban pollution generated by motor vehicles.

I have published some of my research work in various conferences, journals and books. A complete list of my publications are available in my curriculum vitae.