Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [io]

"IO" is an acronym for "Indistinguishability obfuscation". Informally, obfuscating a program is the process of concealing what the program is doing while at the same time preserving its functionality. Among other things this serves to protect against code tampering and reverse engineering.

"Indistinguishability obfuscation" means that if you can encode some "processing" as circuits, so that there are several possible distinct circuits which yield the same results, then indistinguishability obfuscation allows publication of an "obfuscated circuit" in a way that anybody can run the circuit and obtain the result, but no outsider can know or learn which of the possible circuits was internally used as a basis.

For more detailed information, check papers like Candidate Indistinguishability Obfuscation and Functional Encryption for all circuits

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What is Indistinguishability Obfuscation?

I've been studying functional encryption. I recently read that a multi-input functional encryption (MIFE) implies indistinguishability obfuscation (IO). Can someone please brief me: what is indistinguishability obfuscation (IO), and are its…
user45080
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How inefficient are current Indistinguishability Obfuscation (IO) candidates?

Since last year, IO finally seems to be within our reach. Several papers (https://eprint.iacr.org/2020/1003, https://eprint.iacr.org/2020/1024 and https://eprint.iacr.org/2020/1042) proved the existence of IO based on almost-standard…
CryptoPerson
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The notion of sub-exponential security

I have been reading a paper where they construct probabilistic IO (indistinguishability obfuscation) from sub exponential IO. I want to know if the following two notions of sub-exponential security equivalent? A scheme is sub-exponentially secure…
user38956
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Is Indistinguishability Obfuscation Real?

I've recently stumbled upon an interesting Quanta Magazine article. It states that indistinguishability obfuscation (iO) 's theoretical feasibility has been proven, referencing a relatively recent paper by Jain, Lin, and Sahai. However, the…
programonkey
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Advances in Indistinguishability Obfuscation

I hear there's a recent advance in Indistinguishability Obfuscation, aka io, with emphasis on Aayush Jain, Huijia Li and Amit Sahai Indistinguishability Obfuscation from Well-Founded Assumptions (eprint and arXiv, August 2020). For the applied…
fgrieu
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Obfuscating functions that are mostly zero

Let $f_k(x)$ be a boolean function of two arguments with two properties: The function $f$ can be efficiently computed. The output is always 0 or 1, and for any fixed $k$, if we choose $x$ randomly, $\Pr[f_k(x)=1]$ is tiny (say, exponentially…
D.W.
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Virtual Black Box Obfuscator

For which class of circuits does the Virtual black box(VBB) obfuscator exists? If so Why? What are the attempts/further developments made in this topic?
Crypto_Research
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Indistinguishable Obfuscation vs Functional Encryption

What is the difference between Functional Encryption from Indistinguishable Obfuscation? Is one of them having more stronger security than the other?
Crypto_Research
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Types of PRFs and its applications

I was learning about iO from this paper when I noticed the different new types of PRFs. I wanted a clear understanding of the following. What are Puncturable PRF (PPRF)? Why is it defined in the way it is? Applications? What are Statistically…
Crypto_Research
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Sub exponentially hard OWF , PRF and iO

I'm currently reading the work "Obfuscation of probabilistic circuits and Applications' by Canetti Lin Tessaro and Vaikuntanathan 2015. It says sub exponentially hard OWF implies sub exponentially hard PRF ( puncturable PRF) and later again proves…
user38956
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How to prove the security if a circuit is obscured by an IO，where the key generattion algorithm of a functional encryption is used in the circuit?

I want to design a scheme, where there is a circuit C0 which is obscured by an indistinguishability obfuscation (IO). In C0, a master key of a functional encryption (FE) is hardwired. Given an input z to C0, it outputs a secret key using the key…
laolien
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OWF and iO Correlation

What is the relationship between one way functions(OWF) and indistinguishable obfuscation(iO)? I know that iO exists even when P=NP and OWF don't exist. But does the existence of OWF imply iO?
Crypto_Research
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How indistinguishability obfuscation implies unintelligibility of a program?

Given an obfuscator $O$ that takes as input a circuit $C$ and outputs its obfuscated version $O(C)$, we expect, informally, that the obfuscated version should be somehow "unintelligible" for anyone who sees or runs it. In other words, it should be…
Enrico Bottazzi
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Why does iO imply OWF according to Gentry's explanation?

I bumped into this presentation from Craig Gentry in which he explains why iO implies OWF under the assumption that NP is not in BPP. Can you help me understand the proof he provides? I especially don't get why the adversary would succeed in…
Enrico Bottazzi
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Impossibility vs implaussiblity

What is the difference between implausibility vs impossibility in the context of Crypto? I came to know that differing input indistinguishability Obfuscation (diO) implausibile but not impossible. Can I know the difference between the two…
user38956