Small tags/sites
21 tags on

Small tags/sites

RSA, proof of correct work, if p is not a prime number

Is there any proof of correct work of RSA algorithm, if p is not a prime number? For example: n = p*q, p = p1*p2, where p1 and p2 are primes.

Can Poly1305-AES be used with AES-256?

I'm reading through Bernstein's The Poly1305-AES message-authentication code. The MAC is predicated on 16-byte block ciphers like AES and produces 16-byte authentication tags. However, Bernstein does ...

Raoult's Law explained with thermodynamics/ free energy

I got some confusion going on with this explanation of Raoult's Law. This is what my book say: Because the ideal solution has a higher entropy than the pure solvent, the energy of a vapor ...

cryptography system by combining a block cipher and a stream cipher

I have to come up with a design for a cryptography system by combining a block cipher and a stream cipher. I can't seem to come up with anything on my own. Can someone point me in the right direction ...

Find the killer's name

A notorious serial killer going by the pseudonym "N" has dispatched a letter to the FBI after committing 45 homicides. He is characterized to be extremely intelligent and sends mysterious ...

I'm getting the following exception (so far only Android 4.0.4): java.security.NoSuchAlgorithmException: KeyGenerator AES implementation not found at ...

1 answers | 3 hours ago by mntgoat on stackoverflow.com

Encrypted Password corruption - some saved as encrypted, some not encrypted, some not saved

I'm programming a legacy ColdFusion application that uses a 2008 SQL Server database. I know very little about how the SQL Server database was set up, but I'm hoping if I share some of the symptoms, ...

Thick client session management and security

I want to develop a thick client app (instead of using jsp/server side) which I will provide a login panel upon launching of my app. I am not sure whether it is the correct approach (in terms of ...

Prove that if we redefine the key space, we can assume Gen chooses a key uniformly

I am working on problem 2.1 in Introduction to Modern Cryptography 2nd edition by Katz and Lindell. 2.1) Prove that by redefining the key space, we may assume that the key generation algorithm ...

Writing a Java program to encrypt and decrypt a ADFGVX cipher

I need to be able to encrypt and decrypt a message using a Polybius Square. I know how this works on paper but don't know where to start when turning it into a program. I was planning to use a hash ...

What kind of Quantum cryptography technology(protocols) can be used for Mobile Ad hoc networks(MANETS)?

Typically ad hoc networks do not have a proper infrastructure and the routing is done only through the base stations which are connecting a wired and wireless network. Does quantum cryptography ...

Stacked LFSR - why not used?

New to cryptographic, weak in math. I have designed a PRG which consist of 33 LFSR's, each 32 bits wide. I use one of the LFSR's as "selector", using the 5 LSB from this register to select one of ...

EVP keygen fuctions produce identical keys every time

I am trying to generate a unique RSA keypair using the EVP functions and then save it PEM encoded. My tests however have produced a situation where the same key pair appears to be generated each time. ...

Which characters to take into account when calculating unicity distance?

I need to calculate the unicity distance of a block cipher. Assuming I know that the plaintext is an English message I considered using 53 as the size of the alphabet, since the message could contain ...

Difference between .NET 3.5 Cryptography implementation and Mono 2.x implementation?

I have identical code being compiled and run under Mono (Unity 4.5) and MS .NET: DSAParameters privateKey; ... DSACryptoServiceProvider dsa = new DSACryptoServiceProvider(csp); dsa.PersistKeyInCsp = ...

LaTex: Is it possible to vertically center multiple columns in a table?

I've found an example here but that only centers one column and I can't really adapt it to my needs. What I'd like is something like this:

Of what use is my code for finding prime numbers of a certain size?

I've developed a bit of Mathematica code that can find primes within a range of numbers. For example, if I wanted all the primes between one million and two million, it could do that. Of what use is ...

What aspect of elliptic curve encryption paradigms makes them especially susceptible to quantum based attack algorithms?

This was a statement made during a talk at today's DFN-CERT conference but unfortunately it wasn't explained further. Can anyone shed light on why elliptic curves are susceptible to quantum based ...

Error in \begin{document}

Can anyone help me with latex.. This is my main report I was entering reference for report and its giving me error in bibliography \documentclass[fleqn,12pt]{report} ...

Encrypt String AES Windows Phone 8.1

I'm making an app which will need to encrypt a string. I'm completely new to AES encryption. I have to code that runs on the server to encrypt. public static string Encrypt(string text, byte[] key, ...

Is there a means of calculating the entropy of a series of bits that takes correlation into account?

A common expression for calculating the entropy of a series of bits appears to be: $$-\sum_{i}{P\left (x_i\right )log_b\left (P \left (x_i\right )\right )}$$ This seems to fail (or my intuition of ...

Longtable written in latex starts from the next page

I created a longtable in latex for my Appendix A. Appendix A starts with a short paragraph and this table should start right after the end of this paragraph, but it starts from the next page, what can ...

BigQuery: compute entropy of a column

I have a suggestion for the BQ folks: I think it would be very useful if there was a built-in function that would return the entropy of a column. A column of discrete categories or values would be ...

1 answers | 13 hours ago by SheRey on stackoverflow.com

difference between public key and host key and security of host key

In SSH, what is the difference between host key and public key. Public key I believe that is part of private/public key pair, so, that anything sent by server(encrypted using private) can be ...

encrypt and decrypt a video file using AES in php

I have created an upload form which uploads a video file in a destination folder. But I want to encrypt the video using AES when it is uploaded and decrypt it when it is played in a php file. I tried ...

STL Hash Functions

Does the STL have any Hash functions available, that are exposed publicly? I know that there are some non-standard implementations that use hash values (such as boost::hash_map), and MSVC8 implements ...

4 answers | 15 hours ago by J T on stackoverflow.com

Assemble RSA keys from components

I'm studying openpgp cryptography and struggling to understand some things. I can't use pgp tool for generating keys and ecryption, but have to write a simple app to generate keys, encrypt and decrypt ...

Encryption and decryption of a audio/video file using AES(128)

I am writing a program that sends an audio/video file to the server where the data is encrypted and sent back to the client on a socket. In the client part, the data is extracted and is decrypted and ...

2 answers | 15 hours ago by Krish on stackoverflow.com