Computer Science Colloquia
Friday, November 30, 2012
Advisor: abhi shelat
Attending Faculty: Gabe Robins, Chair; Wes Weimer, Steve Myers, and Andrei Rapinchuk, Minor Representative
10:00 AM, Rice Hall, Rm. 242
PhD dissertation presentation
New Designs of Encryption Schemes
Malleability of an encryption concerns the ability of users to compute the encryption of $f(m)$ from the encryption of $m$ for an arbitrary message $m$ and a function $f \in F$. In this context, we say that the encryption scheme is non-malleable if $F$ is an empty set, and we say the encryption scheme is fully malleable or fully homomorphic if $F$ includes any arbitrary function. In some applications the encryption scheme should be non-malleable to preserve the privacy of data while in others malleability of the encryption facilitates the functionality or efficiency of the application.
In this thesis we bring forth several general constructions of non-malleable encryption schemes enjoying different levels of security. We also design a multi-party computation protocol that employs a fully homomorphic encryption scheme to optimize the communication cost.