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Questions tagged [proxy-re-encryption]

a type of public-key encryption scheme that allows to transform ciphertexts encrypted under Alice's public key into ciphertexts decryptable by Bob

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Does Proxy re-encryption can re-encrypt large data?

Many resources talk about the benefit of Proxy Re-encryption (PRE) and I also implement my PRE using Elliptic Curve key pair. But after I set up Global parameters, I can encrypt very small data maybe ...
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Why is a proxy needed in proxy re-encryption?

Context Here's the usual proxy re-encryption scenario: Alice, with key pair $(pk_a, sk_a)$ encrypts a message $m$, producing $c = encrypt(pk_a, m)$ Alice saves $c$ on an untrusted storge provider (...
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Is it possible to delegate re-encryption key generation?

In a non-interactive proxy re-encryption scheme, Alice, with the key pair $(pk_a, sk_a)$, needs to issue a re-encryption key $re_{a\rightarrow b}$ once she wants to share her secret message with Bob, ...
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Application of uni-directional proxy re-encryption?

What kinds of applications is uni-directional proxy re-encryption applicable to? I learned some applications that proxy re-encryption can be used, which are email and file sharing scenarios. All of ...
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Possible to split a secret to generate a re-encryption key (PRE)?

I am wondering, if it is possible to split a secret (s.th. like shamir's secret sharing) which can be used to generate a re-encryption key in proxy re-encryption and only serve the splitted portions ...
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Proxy Reencryption - semi-trust into proxy required?

As far as I understood, PRE claims to hide the underlying message from being read by the proxy. Why can't the proxy simple use a public key of himself as target?
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Additive homomorphic secret sharing

I am new to cryptography esp, homomorphic encryption. I would like to know if the following is possible using something similiar to additive homomorphic secret sharing. Please apologize me if its too ...
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Is there a proxy re-encryption algorithm for Elliptic Curve ECIES?

I was wondering if there is a way to perform proxy re-encryption for ECIES public-key encryption (i.e. given a message encrypted with Alice's public key, re-encrypt it using Bob's public key). Is that ...
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What's the difference between single key-pair public key encryption and proxy re-encryption?

Proxy Re-Encryption provides the ability to transform a ciphertext encrypted under some key to the one under another key. This seems interesting. But, something seems strange. Suppose Alice has a key ...
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105 views

Proxy Re-Encryption with provable re-encryption target

Suppose Alice has encrypted some plaintext $P$ to Bob. Bob wishes to re-encrypt this information to Charlie via proxy, in such a manner that: The proxy cannot obtain $P$ The proxy can prove that Bob ...
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How useful is proxy re-encryption if we end up needing a symmetric key?

I'm trying to design a system using proxy re-encryption (PRE) to allow the sharing of data between a user (delegator) and other users he delegates access to (delegatees). The goal is to use a PRE ...
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391 views

Usage of pairings in proxy re-encryption algorithm

I am having trouble understanding one part of the AFGH algorithm for proxy re-encryption (my background in discrete mathematics is lacking a bit). The paper describes the algorithm setup the ...
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ElGamal proxy re-encryption

I wrote an algorithm to implement a suggestion in a paper by Ivan and Dodis to convert a regular ElGamal encryption scheme into a proxy re-encryption one (it's at page 6, left column of this but I ...
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1answer
92 views

Identity-based proxy re-encryption using different system parameters

I am wondering if there is an identity based proxy re-encryption scheme (such as the Green-Ateniese scheme https://eprint.iacr.org/2006/473.pdf) that converts an encryption computed with ID1, system ...
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Proxy re-encryption mod operations

I managed to implement the proxy re-encryption scheme from http://eprint.iacr.org/2009/189.pdf in Python 2.7, however I am having performance issues. As it is, I can run the algorithm for key sizes up ...
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What scheme will allow merging and splitting the result of a function?

I am wondering if it's possible to have a scheme as follows. Here is the scenario: we have a set of objects (e.g. strings) {O1, O2, ..., On} we have a set of users {U1, U2, ..., Um} each user asks ...
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Is there an encyption scheme that combines additive homomorphism with ability to proxy re-encrypt?

Is there an encyption scheme that combines additive homomorphism with ability to proxy re-encrypt? I've tried digging around on the Internet but haven't found anything conclusive on the topic.
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Can we proxy-re-encrypt using homomorphic encryption schemes?

Homomorphic encryption schemes are PKE schemes with an additional special method Evaluate. The Evaluate method takes input any function (as boolean circuit) and encrypted inputs of the function and ...
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How practical is proxy re-encryption for AES?

In proxy re-encryption schemes, a proxy is given special information that allows it to translate a ciphertext under one key into a ciphertext of the same message under a different key. How ...