Aishwarya Thiruvengadam, PhD Student, University of Maryland, USA
We revisit the question of constructing an ideal cipher from a random oracle. Coron et al.~(Journal of Cryptology, 2014) proved that a 14-round Feistel network using random, independent, keyed round functions is indifferentiable from an ideal cipher, thus demonstrating the feasibility of such a construction. Left unresolved is the best possible efficiency of the transformation. We improve upon the result of Coron et al. and show that 10 rounds suffice. This is joint work with Dana Dachman-Soled and Jonathan Katz.