Research Interests

My research interests center on devising novel mathematical and cryptographic approaches to security problems of real-world interest. Much of my work has focused on the development of new cryptographic primitives, such as the RSA public-key cryptosystem (joint with Shamir and Adleman), the MD5 hash function, the block ciphers RC4, RC5, and RC6, tweakable block ciphers, and various digital signature schemes, such as ring signatures and transitive digital signatures. I have also worked on a mathematical framework (SPKI/SDSI) for naming, credentials, and authorization. My more recent work addresses security and privacy issues arising from recent technical advances. For example, radio-frequency identification (RFID) chips will soon be a common way of labeling objects; yet pervasive use of RFID chips threatens individual privacy. I have developed (with Juels and Szydlo) an RFID "blocker tag" that protects an individual's privacy by selectively blocking RFID readers. As another example, I have developed (with Micali) an efficient probabilistic yet fair micropayment method. Most recently, I have been working on the security of electronic voting systems, emphasizing the maintenance of voter privacy. I have also become more involved in the policy aspects of privacy and of voting.

Membership Type


Election Year


Primary Section

Section 34: Computer and Information Sciences