On Constant-Round Concurrent Zero-Knowledge
نویسندگان
چکیده
Loosely speaking, an interactive proof is said to be zeroknowledge if the view of every “efficient” verifier can be “efficiently” simulated. An outstanding open question regarding zero-knowledge is whether constant-round concurrent zero-knowledge proofs exists for nontrivial languages. We answer this question to the affirmative when modeling “efficient adversaries” as probabilistic quasi-polynomial time machines (instead of the traditional notion of probabilistic polynomial-time machines).
منابع مشابه
Constant-Round Concurrent Zero Knowledge in the Bounded Player Model
In [18] Goyal et al. introduced the bounded player model for secure computation. In the bounded player model, there are an a priori bounded number of players in the system, however, each player may execute any unbounded (polynomial) number of sessions. They showed that even though the model consists of a relatively mild relaxation of the standard model, it allows for round-efficient concurrent ...
متن کاملA Note on the Round-Complexity of Concurrent Zero-Knowledge
We present a lower bound on the number of rounds required by Concurrent Zero-Knowledge proofs for languages in NP. It is shown that in the context of Concurrent Zero-Knowledge, at least eight rounds of interaction are essential for black-box simulation of non-trivial proof systems (i.e., systems for languages that are not in BPP). This improves previously known lower bounds, and rules out sever...
متن کاملConstant-Round Concurrent Non-malleable Zero Knowledge in the Bare Public-Key Model
One of the central questions in Cryptography is the design of round-efficient protocols that are secure under concurrent man-in-the-middle attacks. In this paper we present the first constant-round concurrent non-malleable zero-knowledge argument system for NP in the Bare Public-Key model [Canetti et al. STOC 2000], resolving one of the major open problems in this area. To achieve our result, w...
متن کاملConstant-Round Resettable Zero Knowledge with Concurrent Soundness in the Bare Public-Key Model
In the bare public-key model (BPK in short), each verifier is assumed to have deposited a public key in a file that is accessible by all users at all times. In this model, introduced by Canetti et al. [STOC 2000], constant-round black-box concurrent and resettable zero knowledge is possible as opposed to the standard model for zero knowledge. As pointed out by Micali and Reyzin [Crypto 2001], t...
متن کاملConstant-Round Concurrent Zero-Knowledge from Indistinguishability Obfuscation
We present a constant-round concurrent zero-knowledge protocol for NP. Our protocol relies on the existence of families of collision-resistant hash functions, one-way permutations, and indistinguishability obfuscators for P/poly (with slightly super-polynomial security).
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2008