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Sending encrypted message without public key from recipient (elgamal)

If Bob was using an ephemeral key pair when encrypting for Alice, then Bob would need to send his permanent public key as the message in order for Alice to receive it. There is no way Alice could ...
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Can a MITM during Diffie-Hellman key exchange manipulate both sides to generate symmetric secrets?

Can a MITM during Diffie-Hellman key exchange manipulate both sides to generate symmetric secrets? Let's assume that the MITM attacker can create an exchanged key that is the same on both sides. I.e.,...
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Can a MITM during Diffie-Hellman key exchange manipulate both sides to generate symmetric secrets?

Is it possible for an attacker on a Diffie-Hellman key exchange to manipulate both sides in a way so that the secret generated on each side is identical? If both parties use a well seeded CSPRNG then ...
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Key distribution protocol involves only 2 parties, given E[k1,E(k2,m)]=E[k2, E(k1, m)]

Is there any key distribution protocol that involves only two parties (Alice and Bob) without the key distribution center? Yes, it's Shamir's Three Pass Protocol; it works exactly how you describe. ...
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Sharing RSA private keys using key exchange algorithms like Diffie–Hellman Algorithm?

This is going in the wrong direction, so I'll answer by showing two alternatives: Share e.g. a strong machine generated password for this with enough randomness to pass as a secret key. The reason to ...
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4 votes
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Curve448 - Can Ed448 key material be reused for X448?

You do not need to convert the Edwards448 public key to the birationally equivalent Curve448 public key in order to do ECDH. You can just stick to Edwards448. There will be a performance gain if you ...
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Can Bob and Alice do an authenticated Diffie–Hellman key exchange if Bob only knows the hashsum of Alice's key?

Correct, Bob can be sure there is no man-in-the-middle attack when initiating communication with Alice, as long as he has been reliably informed of the hash of Alice's public key and the hash is ...
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Authenticated Diffie-Hellman with no proofs that each one keys are the right keys. Is it possible?

If what you are describing were possible, then we wouldn't need certificate authorities. The paper you've linked to uses a technique that only works if Alice and Bob already know each other's long-...
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3 votes

Tree Parity Machines (neural cryptography) advantages

After like an hour of search on the subject of Tree Parity Machines as an alternative to Diffie-Hellman key exchange, I found that: It started with this article: Ido Kanter, Wolfgang Kinzel and Eran ...
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