Reading assignment: Hashing

Blockchain and Bitcoin 101
#2291

  1. SHA-256

  2. Because if you spend every second of every day guessing hashes without sleeping, you would be guessing hashes for the rest of your life and you would never even come close.

1 Like
#2292

Hey, it seems the order in the article is switched and you are correct. The hash change would only affect the blocks after the changed block. To be honest I didn’t read the article, but great of you to notice! I will report it to the team and will replace it with a better article. :slight_smile:

3 Likes
#2293
  1. What is the hashing algorithm called used in Bitcoin?
    Bitcoin uses the SHA-256, always has 256 bits length
  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    It is too long and would take too much time to crack it.
1 Like
#2294
  1. The hashing algorithm that bitcoin uses is SHA-256
  2. It is infeasible because there are too many possibilities. Each small change in input results in a drastic change of output.
1 Like
#2295

Thank you, Alko! :smiley:

#2296

Thanks a lot for the observation!
I will check it out and replace this article with a better one :+1:

3 Likes
#2297
  1. Sha-256
  2. Because the probability to find the input based on the output is very difficult due to the large amount of computation involved.
1 Like
#2298
  1. What is the hashing algorithm called used in Bitcoin?
  • It is called SHA-256
  1. Why is this hashing algorithm really hard (almost impossible) to brute-force?
  • It is an astronomical probability for one to do so when applying the brute force method. It simply takes too long time.
1 Like
#2299

What is the hashing algorithm called used in Bitcoin?

The hashing algorithm used in Bitcoin is SHA-256 (Secure Hashing Algorithm 256).

Why is this hashing algorithm really hard (almost impossible) to brute-force?

The difficulty to brute-force is a probability of trial and error of taking random inputs, hashing it and comparing the results. In an algorithm like SHA-256 the probabilities of finding the original input of the hashing or “pre-image” are so high that it would take too much time (more than a lifetime) and computational power to determine it, at least in today’s world.

2 Likes
#2300

SHA-256 is Bitcoin’s hashing algorythem

The hash algorithm is difficult to calculate inputs and outputs because it is infeasible to quickly know with 256 bit size. You have to just keep guessing the missing input over and over until you match the output. With the size of the Hash Algo, it would take human manuelly doing this over a lifetime to figure out one hash. Thats why Bitcoin uses super computers to making so many guesses at the answer until it is figured out.

1 Like
#2301

  1. What is the hashing algorithm called used in Bitcoin? The hashing algorithm is called SHA-256.

  2. Why is this hashing algorithm hard (almost impossible) to brute-force? The Hashing algorithm is really hard and almost impossible to brute-force because it takes an extremely long time to find a collision in the algorithm.

1 Like
#2302
  1. What is the hashing algorithm called used in Bitcoin?
    SHA-256
  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    You will have to try around 2^127 times.
2 Likes
#2303
  1. Sha 256
  2. There are so many different combinations of numbers and letters, it would take thousands of years to guess just one.
1 Like
#2304
  1. sha-256
  2. pre-image resitance makes it infeasible to figure out the input. there are so many possible input values that it would take a lifetime to match up all the hashes to the corresponding input
1 Like
#2305

  1. What is the hashing algorithm called used in Bitcoin?
    SHA-256

  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    Because it´s random, you have so many possibilities and the software keeps going until it reaches its goal.

1 Like
#2306

Answer 1: SHA-256
Answer 2: in order to safely store data. Pre-image resistance : 2^128/2 = 2^127 times which makes it almost impossible, infeasible to hack.

1 Like
#2307
  1. SHA256
  2. The number of computational possibilities is so high with a 256 hash that it would make brute forcing it infeasible.
1 Like
#2308

  • What is the hashing algorithm called used in Bitcoin?
    SHA256

  • Why is this hashing algorithm really hard (almost impossible) to brute-force?
    no matter the input, the output will be always 256-bits long; using a brute-force method it would take a looooooooooot of time to find the correct input to match the output

1 Like
#2309

The hashing algorithim that bitcoin uses is called SHA 256.

It is almost impossible to brute-force because you’d have to try almost an infinite number of combination of digits (2X128) to chance upon the hash. It is so unlikely as to be impractical to even try.

1 Like
#2310
  1. What is the hashing algorithm called used in Bitcoin?
    SHA-256
  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    It has a relatively large number of possibilities, making it harder for errors such as collisions to occur.
1 Like