Questions tagged [order-preserving]
Order-preserving encryption (OPE) is a method of encrypting data so that it's possible to make efficient inequality comparisons on the encrypted items without using the key (including, but not limited to, using the key to decrypt the encrypted items).
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Is Order-preserving encryption part of the functional encryption family?
I believe I know quite well OPE and ORE, but I'm unsure about what family to put them in. Can we consider them as a sub family of Functional Encryption, like Attribute Based Encryption or Inner ...
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How hypergeometric sampling works in order preserving encryption?
According to https://crypto.stackexchange.com/a/8800/53007:
Start with the entire domain [M] and range [N]. Call y←N/2 our range
gap. Now using our key k we generate some pseudorandom coins and give
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Understanding this notation for the probability distribution of order preserving encryption
I'm reading this PDF: https://link.springer.com/content/pdf/10.1007/978-3-642-01001-9_13.pdf about order preserving encryption functions and there's this on page 9 (or 232):
It's describing the ...
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Comparing two private values and extracting the ciphertext corresponding to the minimum value
How can I solve this problem: I have a directed graph of nodes that can be malicious and all of them have a private value.
Consider a node "B" with private value "BPrivateValue = b&...
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Does asymmetric order-preserving encryption exist?
As I understand from this post, mapping from plaintext space to ciphertext space is the fundamental point of all order-preserving encryption. So the only way that we let someone encrypt an arbitrary ...
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NIZK proof for Order-preserving encryption
Suppose a cipher c=Enc(K,m), where Enc() is the order-preserving encryption scheme. Can NIZK be used to prove that c does indeed encrypt m? The Schnorr NIZK is based on discrete logarithms equality. I ...
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Order preserving hashes [duplicate]
Are there hash functions that dynamically take integers a and b, and output h(a) and h(b) such that if a>b we have h(a) > h(b)?
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is OPE able to produce different cyphertext for same plaintext?
Given a plaintext p, is OPE (Boldyreva et al.) able to produce n different cyphertext c1...cn for the n occurrences of p?
If not, there exists an order-preserving encryption scheme able to do that?
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Are large polynomials secure for order preserving "hashing"? (newbie question)
I've been searching for some time now for an answer to this simple question: if I have a large polynomial that is secret, and I use it to transform a set of integers so as to obtain a new set that ...
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Applying machine learning algorithms to homomorphic encrypted data
I have a basic understanding of encryption and I got back to the topic because of an interesting site that encrypts financial data using homomorphic encryption (HE) and I would be happy for any input ...
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Order-Preserving Encryption (OPE) and leakage
I recently came across OPE and Order-Revealing Encryption (ORE), but I didn't exactly got the idea why they are important. What's exactly important about them? Are they actually used in practice? My ...
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How does order-preserving encryption work on string?
I have read “How does order-preserving encryption work?”. After that, I completed order-preserving encryption on integer data.
Now, I have four questions in this subject:
Is it possible to apply sum ...
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Understanding the definition of HGD
On the section 4.2, page 10, of the paper Order-Preserving Symmetric Encryption, the authors define two subroutines: the first one is called $HGD$ and the second one is $GetCoins$.
I have doubts ...
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Additively homomorphic cryptosystem with non-interactive zero-knowledge proof of non-negativity
I need a cryptosystem that is additively homomorphic. Paillier preferably, but not neccessarily.
Also, for every ciphertext the private key holder must be able to prove non-interactively that the ...
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Applying Vigenere on small strings with sorting capability
I am new to cryptography and have a question about a use of Vigenere cipher in the case of small strings. I'd like to encrypt keywords that are smaller than 10 characters.
If I use Vigenere ...
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Is it secure to use order preserving encryption in practice?
When I read papers, I often see the comments, "order-preserving encryption is deterministic and it is not IND-CPA secure", or in general "it is not secure enough to be implemented in practice". So I ...
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What is matrix branching program?
Recently I am reading something about order-revealing encryption (by Boneh at al. in EuroCrypt 2015) and encountered "matrix branching programming". It seems like it took me forever to understand this....
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Weakening of Paillier cryptosystem due to ciphertext equivalence and order in CryptDB
The Paillier cryptosystem is probabilistic in nature and IND-CPA secure. By design given two ciphertexts one cannot distinguish whether decrypting those two ciphertexts will result in same or ...
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Encryption scheme that allows compare ciphertexts based on the clear text [duplicate]
I would like to compare ciphertext based on the order assumed on the message space.
So, do you know if there exists some encryption scheme with the follow property:
Let $c_0 = E(m_0)$ and $c_1 = E(...
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"Practical" operations supported by functional encryption?
I'm curious about what operations have been developed into functional encryption schemes.
What I mean by that is: what operations can be performed over encrypted ciphertexts? Obviously homomorphic ...
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Is an elliptic curve over $\mathbb{F}_p$ order preserving for the points $(x,y) \in \mathbb{Z}_p$?
Let $E\colon y^2=x^3+ax+b$ be an elliptic curve, and consider its realisation over the finite field of prime order $p$: $E(\mathbb{F}_{p})$.
Then if $0<a,b$ is the following true?
$$\forall x,y\...
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Open source implementations of Symmetric Searchable Encryption and Order Preserving Encryption [closed]
Are there open source implementations of SSE and OPE?
Can anyone please point to sample codes, if available.
EDIT
If cryptDB is not an option, what other options are available?
(Indeed, these ...
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Calculating ciphersize of Paillier, SSE and OPE
If I have to encrypt a 32 bit plaintext in each of Paillier, SSE and OPE, how can I make an estimate of the ciphertext sizes respectively in order to reserve the amount of space in a database?
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How secure is this use of Ziv-Lempel encoding?
I'm reading patent application US 20120278897 A1 — “System and method of sort-order preserving tokenization”. Near the bottom they describe their token generation algorithm, which basically involves ...
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Secure order preserving hash function
Is there a construction of an order preserving hash function that keeps the preimage property of a crypto hash function? By order preserving hash function (OPHF) i mean for $x<y$ then $OPHF(x) < ...
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In the Paillier cryptosystem, is there a method to judge whether an encrypted number is less than 0 (without the private key)
Or, is there a cryptosystem that is both order-perserving and additive homomorphic?
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How does order-preserving encryption work?
Order-preserving encryption (OPE) is, apparently, a method of encrypting data so that it's possible to make efficient inequality comparisons on the encrypted items without decrypting them.
I've been ...
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Order Preserving Encryption for Numeric Data Values
How can I ensure order of encrypted data i.e., Enc(m1) < Enc(m2) where m1 < m2, and all messages are integer values.
I have gone through Order Preserving ...
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