Vitalik Buterin reviews indistinguishability obfuscation and its blockchain potential

Vitalik Buterin published “Obfuscation: building the final boss of cryptography (Part I),” describing indistinguishability obfuscation, or iO, as a long-running cryptographic goal and calling obfuscation the most powerful primitive in cryptographic history. He said it could eventually turn software into an encrypted program that runs on cleartext inputs without exposing its internal logic. Paired with a blockchain, that could move some applications closer to a trustless trusted third party, including secure private voting systems that are resistant to collusion and do not rely on an M-of-N threshold committee. Buterin also stressed that secure obfuscation remains far from practical. He noted that ideal obfuscation was proven impossible in 2001, and said current provably secure constructions, built by stacking tools such as fully homomorphic encryption, functional encryption and lattice-based techniques, still carry runtimes that can exceed the lifetime of the universe. He said practical iO still requires orders-of-magnitude runtime improvements before deployment.