Questions tagged [homomorphic-encryption]
Cryptosystems which support computation on encrypted data. They might be partially homomorphic (support for one operation such as + or *) or they might be fully homomorphic (any sequence of + and *).
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Homomorphic Max For Two Distances
I have a interesting geometric problem involving distances on a finite plane. I'll provide the unencrypted mathematical background and proof and after that pose the question as it pertains to HE.
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Is the XOR of hashes a good hash function?
Definitions:
Let $h$ be a hash function with output size $n$ bytes. Suppose the file $F$ can be divided into chunks of size $n$ bytes $F=f_0+f_1+\dots +f_i$ where the operator "$+$" stands ...
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Difference between TFHE and CKKS?
What are the differences in parameters while implementing CKKS vs TFHE?
For example modulus size, ring dimensions, bit security. Any pointers to literature would be appreciated
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Is there any bound on the size of ring dimension for Torus FHE?
I see that all implementations of TFHE in opensource supports 2^10 to 2^12 size of ring dimensions. Is there any specific reason (crypto) behind choosing the value or can we choose higher dimensions (...
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Does the use of OPRF or OT remove the need of HE in PSI?
I was reading a systematic literature review on Private Set Intersection (PSI) protocols (https://www.sciencedirect.com/science/article/pii/S1574013723000345#sec8), which mentions that the main ...
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Is ElGamal homomorphic encryption using additive groups works only for Discrete Log ElGamal? What about EC ElGamal?
It is known that in Discrete Log ElGamal encryption, the ciphertext $E$ is encrypted as:
$a\ =\ g^k$, where $k$ - random scalar from $[0,\ p)$, $g$ - group generator
$b\ =\ (Y^k*m)\mod\ p$, where $Y$ -...
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Can there be fully homomorphic encryption with this property?
Lets say Alice has data D and wants to send this data for Bob to process it with algorithm A. Is it possible to encrypt D so that it can only be used to run algorithm A? Alice and Bob will communicate ...
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Formal connection between fully homomorphic encryption schemes and field homomorphism
In fully homomorphic encryptions schemes (FHE), we aim to preserve both additional and multiplication operations in the encrypted space such that the operations can be decrypted later. This concept ...
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Question Regarding Idenitities of Gentry's Homomorphic Encryption on LWE
In the paper Homomorphic Encryption from Learning with Errors: Conceptually-Simpler, Asymptotically-Faster, Attribute-Based Gentry introduces the following identity $\mathbf{a} \in \mathbb Z^n,\mathbf{...
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Zero-Knowledge Proof of a number being generated "randomly" (similar to a dice roll)
If party1 asks other parties to give a random number, for simplicity, say in a range from 1 to 6 (like in a dice). Is it possible for party1 to ensure that the number received is in a given range and ...
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Mental Poker: Can the shuffle of the deck be done Publicaly by a single player at the start of the game
Ref: Mental Poker Revisited by Barnett and Smart.
I am looking at mental poker problem.
Generally, the shuffling process is done by a single player who starts the game and not by all players.
But, in ...
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Where are the bad and good lattice basis for LWE's ciphertext: (as+e+Δm, a)?
Letś talk about LWE with 2 dimensions. I've seen somewhere they talking about encrypting with the good basis (public key) and then only the bad basis can decrypt.
I assume that the bad basis is the ...
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Can Batch Encode and Bootstrapping Be Used Together
I have referenced some documents stating that "To implement bootstrapping, the plaintext modulus 𝑡
needs to be chosen as a prime power." Meanwhile, the SEAL library documentation on Batch ...
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Real-or-Random Security (IND$-CPA) for Homomorphic Encryption?
I am reading papers about homomorphic encryption recently. To my knowledge, all of them opts for the Left-or-Right security i.e. distinguish between $M_0$ and $M_1$ given $\mathcal{E}_K(M_b)$ for $b \...
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Literature on Batching in FHE
From what I understand, the folklore way to batch Ring-LWE style cipher texts is to use the Chinese remainder theorem. I am wondering if there are any different approaches/optimizations to this style ...
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