CT-ISG: Practice-Oriented Provable-Security for Emerging Cryptographic Applications

University Of California-San Diego, La Jolla CA

Investigators

Abstract

Proposal Number: NSF 0524765 TITLE: CT-ISG: Practice-Oriented Provable-Security for Emerging Cryptographic Applications PI: Mihir Bellare Practice-oriented provable-security, as developed in the nineties, has been successful at delivering cryptography that is both practical and backed by provable-security guarantees. Several mechanisms designed via this approach, such as HMAC and OAEP, are now widely deployed and standardized. (Eg. HMAC is in Internet security protocols SSL and SSH.) The approach has so far however mostly concentrated on the problems of basic communication. This research moves the approach to higher level protocols; it scales the approach to the next level. The work pinpoints various kinds of practical issues peculiar to high-level protocols and addresses them. Since the fee a server can command for advertising placed on its web site is a function of the number of visits it receives, there is incentive to inflate the count, meaning claim or generate fake visits. This research aims to design accurate and flexible metering schemes to prevent this fraud. It also aims to find more practical means for public-key based broadcast encryption, in particular reducing the burden imposed on the public-key infrastructure by current solutions. It also aims to reduce the occurrence of false positives in current methods for encryption with keyword search, which permits a gateway to route email to different places based on an encrypted keyword. Finally, it aims to improve the efficiency of identity-based cryptography.