A commutative encryption system allows a message encrypted with two different keys to be decrypted using the keys in either order.

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Can CFB mode of block cipher be used as a commutative encryption?

Can CFB mode of block cipher be used as a commutative encryption? Is it possible to use CFB mode of AES block cipher to create commutative encryption? With CTR it is possible but not secure.
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Is this commutative encryption protocol secure?

My assumptions are: encryption must be commutative man-in-the-middle is not an issue I would like to implement the following scheme between 2 parties ($A$ and $B$) to exchange a key: Lets $C = P ...
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Are there transitive ciphers (either symmetric and asymmetric)

Say Alice has information that's already encrypted with Bob's key. She wants Bob to decrypt it without knowing what he just decrypted. So she encrypts it with her key and sends it to him, he decrypts ...
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Is there a mental poker algorithm that does not rely on commutative encryption?

The algorithm for mental poker that I saw on Wikipedia and everywhere else relies on an encryption algorithm such that $E_k(E_j(P)) = E_j(E_k(P))$, but I can't find a modern and secure algorithm for ...
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Crypto libary with Commutative Encryption

I want to implement Mental Poker in JavaScript as a toy program and lead in to a larger serious project so I did my research and found Massey-Omura cryptosystem and the Shamir three-pass protocol ...
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Decrypting an encrypted text out of order

Does there exist a cipher that can be encrypted twice with two different keys and then decrypted twice using either key first? For example: ...
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Commutative Encryption with RSA scheme?

I wanted to know how I could manage to do what I'm going to tell you next, with the RSA encryption/decryption scheme. So Alice and Bob each have a public key $(n, e)$ and a private key $(p, q, d)$; ...
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Can a commutative block cipher be indistinguishable from a random one, assuming a random permutation of keyspace?

Define a commutative block cipher with keyspace the finite set $K$, and message space the finite set $S$, to be an application $$\begin{align} E:K\times S&\mapsto S\\ (k,x)&\mapsto ...
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Can a commutative block cipher be indistinguishable from a random permutation, for fixed key?

Define a commutative block cipher with keyspace the finite set $K$, and data space the finite set $S$, to be an application $$\begin{align} E:K\times S&\mapsto S\\ (k,x)&\mapsto E(k,x)\text{ ...
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Can we decrypt in this order when the message is encrypted twice?

If we encrypt a message twice with symmetric key $k_1$ first and then $k_2$ like $E_{k2}\{E_{k1}\{m\}\}$ , ideally we should decrypt with $k_2$ first and then $k_1$ but is it possible to decrypt with ...
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Are there any secure commutative ciphers?

This answer lists two commutative cipher algorithms - Pohlig-Hellman and SRA. However, they don't appear to be too secure. My question is, here there any commutative ciphers out there that are secure ...
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Transparent cipher

I'm trying to implement this protocol: Alice has her permanent key $K_1$. She computes $E(K_1, P)$. She wants to share $P$ with Bob, Carol and Dave. For each of them she: 2.1. Generates $K_2$. ...
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Software implementation of a commutative cipher?

I've got an application (detailed below) that calls for the use of a cipher that is commutative. I've been doing some googling & reading, and there are two algorithms that seem to get mentioned ...