Pay-as-you-Go investigates security and privacy for Integrated Transportation Payment Systems (ITPS). The research addresses integrated payments for trains, subways, buses, ferries, and recharging of electric cars, as well as toll collection for roads, bridges, and tunnels. Multi-disciplinary aspects include novel cryptographic protocols and lightweight implementations of privacy-preserving payment systems. Challenges include providing security and privacy in a low-cost, usable, and reliable manner. Payments for transportation differ significantly from general-purpose e-commerce in terms of both security and engineering constraints. For instance, transportation operators wish to observe user behavior to improve the overall performance of the system---seemingly contradicting privacy. Moreover, payment devices must be extremely cheap, mass produced, and tolerant of a wide range of passenger demands. The expected results and activities include: (1) design of novel cryptographic algorithms achieving privacy at low cost while retaining the benefits of meaningful data collection for ITPS; (2) implementation of hardware and software to perform modern cryptographic operations on low-cost devices; and (3) testing of human factors and performance under realistic conditions that must balance security and privacy with cost and usability. The broader impacts are extensive as transportation systems are a critical part of most aspects of society, from the economy, to defense, to public safety. Moreover, information gathered from ITPS applications can facilitate advanced traffic management, travel time estimation, emergency management, congestion pricing, carbon emissions control, and environmental justice assessments. A substantial outreach plan builds on the research team?s significant experience working with transportation professionals in industry and government.
