# Asymmetric Cryptography & Hashing

## Recommended Posts

Hello,

I have recently been looking into some cryptography related topics however I am still unsure about whether or not hashing falls under the category of asymmetric cryptography, it seems when people are discussing asymmetric cryptography hashing comes into the conversation, but no one seems to mention if hashing is actually considered an asymmetric method.

If anyone knows please do tell as I can't seem to find the answer anywhere!

Thanks :)

##### Share on other sites

Asymmetric cryptography is where two different keys are used to encrypt and decrypt data. Hashing is one way encryption and is mathematically impossible to be reveres without a brute force attach, at least, that's how it's supposed to be.

##### Share on other sites

Asymmetric cryptography is where two different keys are used to encrypt and decrypt data. Hashing is one way encryption and is mathematically impossible to be reveres without a brute force attach, at least, that's how it's supposed to be.

So for an algorithm to fall under the category of hashing it MUST be one way?

##### Share on other sites

So for an algorithm to fall under the category of hashing it MUST be one way?

Yes, other wise it is symmetric or asymmetric encryption.

##### Share on other sites

Ah right, that clears things up a lot, I thought hashing was determined by it creating a fixed size of ciphered text regardless of the quantity of input.

Thanks a lot for the replies, really helped :)

##### Share on other sites

But with most hashes there are always collisions (because it is taking text that is bigger and making it a smaller hash).

For example say there is a hash foo

foo outputs a 1 char string... ok

well there is only x amount of possible chars for 1 character, lets say we are using abcdefghijklmnopqrstuv as what any has consists of so for a through z we take up all possible combinations so if we input ab into hash foo there will be a collision... of course hashed strings are longer then 1 char but still same thing applies

##### Share on other sites

Ah right, that clears things up a lot, I thought hashing was determined by it creating a fixed size of ciphered text regardless of the quantity of input.

Thanks a lot for the replies, really helped :)

I don't think a hash has to create a fixed size output it is just that most of the popular algorithms do.

A hashing function could just be to add up all the ascii values of the plaintext, it would be pretty poor for some situations as collisions could easily be found but it would still be a hash.

##### Share on other sites

One good link to encryption talk is to go to security now and look up their several part talk of asymmetric and symmetric encryption

Really helped me understand it

## Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

×   Pasted as rich text.   Paste as plain text instead

Only 75 emoji are allowed.

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×