| Speaker: Lukas Zobernig Affiliation: University of Auckland Time: 14:00 Friday, 24 November, 2017 Location: 303-G14 |
| Generally speaking, program obfuscation tries to hide a program's logic from a snooping adversary. Ideally, we would like the obfuscated version of a program to be a 'virtual black box', unfortunately one quickly finds that this wish poses many problems. Here we shall instead restrict our view to a special class of programs, called branching programs, that are representations of logic circuits by a sequence of group elements. We will review Barrington's theorem that guarantees the existence of polynomial length sequences for a special class of circuits. Finally, we will see how group representations and multilinear maps based on lattice problems allow us to obfuscate these branching programs. |