# All Questions

107 views

### What values constitute failing for ENT tests?

The dieharder tests give a clear PASSED, WEAK, etc and I'm wondering what those thresholds ...
107 views

### Cryptography in wireless medium

How do I implement asymmetric key algorithm into wireless medium using NS 2.35? For example: node $A$ is a sender and $B$ is a receiver. Now, $A$ is sending a packet using $B$s public key ...
90 views

### Why we need ECDSA when we have ECDH?

ECDSA and ECDH give us the following methods: ...
286 views

### How to crack SHA256 only letters

I recently created a program that hashes a password using SHA256 and potentially using salt. How can I crack that if I know that the password only contains lowercase letters?
51 views

### Degenerate discrete logarithm in binary field

Given a field $\mathbb{F}_{2^n}$, are there any choices of primitive element $g$ that make the discrete logarithm easier for that generator? That is, are there any degenerate cases? For example, if I ...
84 views

### What is the difference between a PRF and a PRF+?

What is the difference between a PRF and a PRF+? I am understanding them to mean the same thing, but I imagine that is because I don't understand their differences. The IKE RFC defines a PRF as: ...
85 views

### Using password-based encryption as a hashing scheme

Classic scheme: Given password and hashing algorithm Generate salt Calculate ...
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58 views

### Using similar passwords and salts for PBKDF2

I'm trying to generate a bunch of pseudo-random keys for AES using PBKDF2, where the AES ciphers will be used in CTR mode as pseudo-random number generators. My goal is to create a 2-dimensional ...
284 views

### Creating unique keys with md5

The project I'm working on requires me to find a way to create a unique key based on data stored in a table. The table in question consists of x columns and y rows. In order to create the key I want ...
92 views

### Common reference string in NIZK

I want to ask that does the common reference string in NIZK have to be random? Or can it be anything?
97 views

### Replay Attack in Stream Cipher

Stream ciphers are vulnerable to replay attack if the same key k is used. If E() is a stream cipher and an attacker intercepts the message m that's being transmitted at time t, how can the attacker ...
585 views

### Decrypt AES-encrypted data with another key

Here is a plain question, all filled with pseudo-real data :) We have a string: "hello" and two keys for AES: GoodKey and BadKey. We encrypt our string with GoodKey, and receive something like ...
2k views

### Key sizes supported by 3DES

I read about 3DES encryption but I don't understand exactly what the specific meaning of key size is. For example I found that 3DES supports 64, 128, 192, and 256 bits key size. What are all the ...