The standard zero knowledge notion is formalized by requiring that for any probabilistic polynomial-time (PPT) verifier V ∗, there is a PPT algorithm (simulator) SV ∗ , such that the outputs of SV ∗ is indistinguishable from real protocol views. The simulator is not permitted to access the verifier V ∗’s private state. So the power of SV ∗ is, in fact, inferior to that of V ∗. In this paper, a ...

Lossy trapdoor functions enable black-box construction of public key encryption (PKE) schemes secure against chosen-ciphertext attack [18]. Recently, a more efficient black-box construction of public key encryption was given in [13] with the help of chameleon all-but-one trapdoor functions (ABO-TDFs). In this paper, we propose a black-box construction for transforming any ABO-TDFs into chameleo...

In this paper, we continue the study the round complexity of black-box zero knowledge in the bare public-key (BPK, for short) model previously started by Micali and Reyzin in [11]. Specifically we show the impossibility of 3-round concurrent (and thus resettable) black-box zeroknowledge argument systems with sequential soundness for non-trivial languages. In light of the previous state-of-the-a...

History of Black Box The initial idea of Black Box can be traced to two-port networks (quadripoles) that were created by a German mathematician, Franz Breisig, in 1921.1 In 1941, twenty years later, Wilhelm Cauer, another German mathematician and scientist, applied this idea in electronic circuit theory.2 Norbert Wiener, an American mathematician and philosopher, defined a Black Box to be an un...

We present a unified framework for obtaining black-box constructions of Universal Composable (UC) protocol in trusted setup models. Our result is analogous to the unified framework of Lin, Pass, and Venkitasubramaniam [STOC’09, Asiacrypt’12] that, however, only yields non-black-box constructions of UC protocols. Our unified framework shows that to obtain black-box constructions of UC protocols,...

The simulation paradigm is central to cryptography. A simulator is an algorithm that tries to simulate the interaction of the adversary with an honest party, without knowing the private input of this honest party. Almost all known simulators use the adversary’s algorithm as a black-box. We present the first constructions of non-black-box simulators. Using these new non-black-box techniques we o...

We prove in a non-black-box way that every bounded list and set commitment scheme is knowledge-binding. This is a new and rather strong security condition, which makes the security definitions for time-stamping much more natural compared to the previous definitions, which assume unpredictability of adversaries. As a direct consequence, list and set commitment schemes with partial opening proper...

—This paper demonstrates a model for Black Box CPU which is a part of Advanced Network Architecture (ANA) PC. The Black Box does not require any electronic or electrical devices; it uses optical devices for processing and storing of data. ANA is used for advanced networking operations. The Black Box is the part of the ANA PC, which serves as a generic CPU with fast processing and huge storage o...

Let L be a language decided by a constant-round quantum Arthur-Merlin (QAM) protocol with negligible soundness error and all but possibly the last message being classical. We prove that if this protocol is zero knowledge with a black-box, quantum simulator S, then L ∈ BQP. Our result also applies to any language having a three-round quantum interactive proof (QIP), with all but possibly the las...