## Computer Science Colloquia

Friday, November 30, 2012
Mona Sergi
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.