Verifiable Random Oracles

https://i62bbb.tm.kit.edu/b/mic-7xx-rfr

2021-06-29

16:15

This is the presentation to the master's thesis "Verifiable Random Oracles".
The goal is to instantiate the Random Oracle used by the Fiat-Shamir transformation, without losing security.
We achieve this goal by defining suitable interactive protocols.
As one of the strengths of the Fiat-Shamir transformation is non-interactivity, we try to reduce the network overhead.
This lead to the novel notion of verifiable random oracles.
These are adapted random oracles, which return proofs of correct evaluation alongside the random value.
With such a proof, any party can check the correctness of a random value locally, without making another query, hence "Verifiable Random Oracle".

This presentation will show challenges in the construction of instantiations for (Verifiable) Random Oracles, i.e. programmability and corruption.
It will also be demonstrated, how the presented instantiations overcome these challenges.