CS Colloquium on Wednesday, June 9, 2004 Title: Private Transaction Management through Autonomous Oblivious Data Mining Speaker: Aggelos Kiayias University of Connecticut Date: June 9, 2004 Time: 11am Place: MCS 135 Abstract: In many systems, privacy regulations/concerns mandate privacy (anonymity) and personal data protection provisions. On the other hand, system management and system integrity constraints may require monitoring user activities and aggregate activity reporting (for billing, statistics, misbehavior detection, etc.). In this work, we suggest a new concept which we call "private transaction management" that achieves the above conflicting goals simultaneously. It allows users to transact anonymously, yet the layer of system management is capable of calculating and reporting the transaction data at an aggregate level. Furthermore, the aggregate information may reveal unacceptable patterns of user's misbehavior, in which case the system may react by privacy revocation. To realize the concept, we design a new credential mechanism for private transactions which allows the above balanced functionality and combines ideas from group signatures with a novel component called "autonomous oblivious data mining engine." This component enables efficient server-based evaluation of aggregate functionalities from the raw transactions data while maintaining user privacy. [Joint work with Shouhuai Xu (U. Texas San Antonio) and Moti Yung (Columbia U.) ] Host: Leonid Reyzin (http://www.cs.bu.edu/~reyzin)