Hello Everyone,

We are having another lunch seminar tomorrow at Noon in 4201. Scott Weeks has volunteered to present this week. No pizza again this week,  so bring your own lunch. I'm also looking for a presenter for next week.

Abstract:

We consider cryptographic systems that use public key encryption (PKE) as a building block in a larger system. We call these cryptosystems "PK-hybrid protocols," and develop a framework for describing such protocols that provides a clear way of describing the role of PKE in the PK-hybrid protocol. By
clarifying and generalizing the role of PKE in such protocols, we are able to state and prove a powerful lemma for proving the security of PK-hybrid protocols. We then show how this lemma can be used in a proof of security for the standard technique of hybrid encryption, substantially simplifying earlier proofs by Cramer and Shoup and by Abe, et al.