Linked Questions

1 vote
0 answers

In symmetric searchable encryption are the algorithms public? [duplicate]

If a user (other than the data owner) possesses the secret key in symmetric searchable encryption scheme are they able to run the trapdoor algorithm, or is this not publicly available?
crypto1's user avatar
  • 11
177 votes
7 answers

Why can't we reverse hashes?

First off, I know hashes are 1 way. There are an infinite number of inputs that can result in the same hash output. Why can't we take a hash and convert it to an equivalent string that can be hashed ...
Hello World's user avatar
  • 1,887
29 votes
9 answers

Why not the one-time pad with pseudo-number generator

I am very new to cryptography (so be kind), but I have a question that may seem silly. If the one-time pad is the perfect cipher and impossible to crack, why would the following algorithm not be one ...
dardawk's user avatar
  • 401
68 votes
2 answers

Is truncating a SHA512 hash to the first 160 bits as secure as using SHA1?

I am from a web development background (I don't know an awful lot about cryptography or how the algorithms themselves work), so I am asking this question in simple terms. Consider a hash of the word '...
BadHorsie's user avatar
  • 813
30 votes
4 answers

How cryptographically secure was the original WW2 Enigma machine, from a modern viewpoint?

If cryptanalysts today were to crack the original Enigma machine, “how fast” or “how easily” could they do it? What methods would they use? The original cracking was significantly helped by operator ...
vsz's user avatar
  • 513
23 votes
3 answers

How to publish a cipher (concept)?

In the last months I was searching for a subject for my bachelor thesis. I came up with an idea for a new cipher concept that works by combining already known techniques in a (hopefully) new way. So ...
masinger's user avatar
  • 463
3 votes
4 answers

Is a Mersenne-twister cryptographically secure if I truncate the output?

I want to create an online roulette game. Is it OK if the PRNG is seeded only once, when the user starts the game, or is it recommended to re-seed sometimes during game? Maybe just seeded once a day ...
user avatar
9 votes
4 answers

Does exposing algorithm, key size and IV weaken the security?

I am using an encryption program to encrypt my documents. Previously I have used PGP and AxCrypt, so I just wanted to see how this new tool encrypts the file. This tool is keeping parameters like ...
RPK's user avatar
  • 571
9 votes
4 answers

Is there a way to generate sound one-time pads out of public information?

Is there a way to 'mangle' a public data-source (for example, the current date in YYYYMMDD or the top New York Times headline) to form a one-time pad that will sufficiently hide the pad's source? ...
pointernil's user avatar
1 vote
3 answers

Writing your own Encryption algorithm?

Simple answer (and I know this is a simple yes or no) is it possible to write an encryption that is 100% uncrackable, as long as I keep certain parts private? It's just for personal use. I'm a ...
Jan Sweet's user avatar
4 votes
4 answers

Are specially designed fonts sometimes used in cryptography?

As a font designer, I was thinking that it would be very easy to design a special font that could either jumble characters of a language (or of a code) or simply (with the features offered by the OTF ...
MicroMachine's user avatar
9 votes
1 answer

Why are cryptography algorithms not exported to certain countries?

There have been strict laws about the export of crypto software to certain countries. I can understand the intent, but never gauged the fact that there is nothing stopping these countries from ...
eminemence's user avatar
0 votes
2 answers

What are the exceptions to Kerckhoffs's principle?

Kerckhoffs's principle: A cryptosystem should be secure even if everything about the system, except the key, is public knowledge. Yet the following are three exceptions:- NSA Suite A cryptographic ...
Paul Uszak's user avatar
  • 15.5k
1 vote
3 answers

Any benefit to writing a message as a mix of 2 languages before encryption?

For example, imagine a message that is a mix of Japanese and English words; Japanese in unicode, English in ASCII. Japanese doesn't use spaces between words. The sentence structures, anything ...
Just Someone's user avatar
4 votes
1 answer

Making my steganography code more hard to detect and crack

I'm doing a college project about digital image steganography on MATLAB. So far i've been able to get the help i needed from cool guys on stackoverflow but i now need to make my algorithm more hard to ...
Ahmed Ihsan Tawfeeq's user avatar

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