Increase the security and customer privacy of transportation payment systems, while allowing for convenient payment and the collection of meaningful data.


Pay-as-you-Go is a multi-disciplinary research project that investigates security and privacy in Integrated Transportation Payment Systems (ITPS). One of the challenges is to find novel cryptographic protocols and lightweight implementations of privacy-preserving payment systems that are suitable for use in ITPS.

Due to the high volume of customers in transportation systems, payments must be executed quickly, lending itself to the use of electronic payment devices. While it is beneficial to collect data about user behavior to facilitate traffic management, estimate travel time, provide emergency management, and control carbon emission, it is also important to preserve user privacy. The Pay-as-you-Go project explores, what data is necessary to enhance the performance of a transportation system, and how to ensure that no more than this data can be collected, and the collected data cannot be assigned to a certain customer. Since transportation payment devices are mass produced, they need to be very cheap, while meeting these requirements.

The project includes a diverse team of computer scientists, electrical and computer engineers and transportation engineers. The team develops novel cryptographic algorithms for the ITPS application whose efficiency is suitable, and that allow for collecting useful data and yet guarantee privacy at the same time. It also explores emerging hardware architectures and software for performing modern cryptographic operations on low-cost devices. And it tests human factors and performance of privacy-preserving payments under realistic conditions of emerging transportation payment systems that must balance security and privacy with cost and usability.


Technical Reports

Research Associates

Graduate Students

Undergraduate Students

  • Luis de Oliveira
  • Neuza Pedro
  • David Prairie

Graduate Alums


Any opinions, findings, and conclusions or recommendations expressed in these materials are those of the author(s) and do not necessarily reflect the views of the sponsors.

  • NSF: grant #0964641