All Questions
Tagged with symmetric diffie-hellman
22
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Is it possible to use Diffie-Hellman protocol for symmetric group?
I was asked this question during one of my first cryptography classes, and I'm not sure if I understand it correctly. To begin, I know that after using the Diffie-Hellman protocol (which itself is ...
- 11
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Why do we need to use Asymmetric cryptography if Diffie-Hellman solves the key exchange problem of symmetric cryptography?
I am new to cryptography and I cant get my head around this issue:
If symmetric cryptography is faster then asymmetric and given that Diffie-Hellman key exchange algorithm allows you to exchange keys ...
- 157
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Sending encrypted message without public key from recipient (elgamal)
assume Bob and Alice use Elgamal encryption scheme. Alice wants to send Bob a message, but does not know Bobs public key. Is there a way for Alice to find out Bobs public key by receiving multiple ...
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Is Diffie-Hellman Key Exchange an Asymmetric or Symmetric Algorithm? [duplicate]
To my understanding, the DHKE algorithm is symmetric since it only produces a shared secret, rather than public and private keys, however googling "is diffie hellman asymmetric?" results in ...
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How can we link AES with Elliptic Curve Diffie-Hellman Key Exchange Method
Actually, I am working on a project to combine symmetric and asymmetric cryptographic algorithms.
The shared secret key for AES will be generated through the Elliptic Curve Diffie Hellman Key Exchange ...
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Is there any standard present to measure strength of a generated key using true random number generator?
I was wondering how to measure the security strength of a generated secret key for the below protocol:
"A 128 bit random number is generated by TRNG and the random number will be used as a ...
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Questions about Symmetric Encryption part of TLS
In TLS, we use DHKE for establishing the session key & then encrypt the actual communication with session key using symmetric encryption. While reading about DHKE, I learnt that you could use the ...
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Key strength comparison: symmetric key vs RSA/DH key
I came across different reputable sources quoting different equivalent symmetric key strengths for RSA/DH keys. This NIST paper (page 67) states the following offer corresponding security strenghts (...
user80928
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Using Diffie Hellman with a shared secret
For a crypto course I need to realize a small software project where a client and a server want to communicate over a unsecured network. They both have the same secret. So I bascially have to secure ...
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247
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How does the key agreement process take place in Virgil E3Kit SDK for end to end encryption?
I'm using Virgil E3Kit SDK to implement end-to-end encryption in my App. Their E3Kit SDK is very effective and not too hard to understand, but I still don't understand how does the key agreement ...
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349
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Detect MITM with hashed session-key — Is my protocol secure?
I have the following setup:
An app ("client") wants to communicate securely with a device I created ("server").
The client has the public key of the server (and a hashed password) preinstalled.
I use ...
- 23
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Multi-Party Offline Key Exchange Using Public and Private Keys
I hope the title already explains the problem I have in mind; but let me lay out some more details.
Given public-private key pairs $P_A, P_B, P_C, ... P_Z$, (first $3$ of which are owned by our usual ...
- 591
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After ECDH with Curve25519, is it pointless to use anything stronger than AES-128?
Is the following reasoning correct:
After ECDH with Curve25519, the resulting shared secret will be an EC public key with a bit strength of 128 bits.
This public key would then be hashed (let's say ...
- 4,740
3
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3
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Establish more secure symmetric crypto system given A and B have small initial secret
Alice and Bob have a secret number X that is known only to them. However, the number is only 14 bits, and Trudy knows they share such a secret and can intercept messages between them. Instead of using ...
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What kind of symmetric-key algorithm to use with Diffie-Hellman?
Let's assume we use DH with a cyclic group modulo p. As I know safe length of p must be at least 1024 bits. That means that ...
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