Reading assignment: Hashing

Blockchain and Bitcoin 101
#2231
  1. It’s called SHA-256 - Secure Hashing Algorithm 256 bits
  2. Because it’s pre-image resisting, meaning that the function is an output hash. In order to find the original Input you have to use the brute-force method which means that you have to guess the Input > hash it > and match it with the Output hash. This would take an enormous amount of time and luck to crack, making it infeasible, but not impossible, to determine the original Input.
3 Likes
#2232

  1. What is the hashing algorithm called used in Bitcoin?
    Secure Hashing Algorithm 256 (SHA-256).

  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    The average time it takes to brute-force the hashing algorithm is so long compared to our lifespan it is considered practically impossible.

1 Like
#2233
  1. SHA-256
  2. Due to the amount of time it would take to find out the input from the output
1 Like
#2234

A1: SHA-256

A2: Brute force input for a SHA-256 hash would require up to 2^256 attempts to find the correct output.

1 Like
#2235

Thank you! It was getting late. I was getting tired! :smile:

#2236
  • SHA-256
  • Because there are so many possibilities , it is almost impost impoosible to reproduce a hash. It would take a long time and the brute force is amount of computation that is required to find 2 inputs to create the same output hash.
1 Like
#2237
  1. The hashing algorithm used in Bitcoin is called SHA-256.
  2. This hashing algorithm is hard to brute-force as it takes too long.
1 Like
#2238

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

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

Because it’s infeasible to try and guess every hash for every block for over 10 years. May need some help answering this question better.

1 Like
#2239

*** What is the hashing algorithm called used in Bitcoin?**

PoW SHA-256

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

The total number of possibilities is so large that it is almost impossible two people get the same result, ever.

1 Like
#2240
  1. What is the hashing algorithm called used in Bitcoin?

SHA-256

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

The brute-force method means that you have to pick a random input, hash it and then compare the output with the target hash and repeat until you find a match.

Best case scenario: Get it on the first try. (Not likely)

Worst case scenario: Get the answer after 2^256 – 1 times.

Average scenario: Maybe find it somewhere in the middle; 2^256/2 = 2^255 times = 5.78 X 10^76.

This means that unless you are extremely lucky, you will need a terribly long time to brute-force

2 Likes
#2241

  1. SHA-256

  2. Because it is “Pre-image Resistant”. It means it is infeasible to determine the input data based on the output hash, it would take (on average) more than a lifetime to brute-force attack.

1 Like
#2242
  1. sha-256
  2. It takes too long time to find it due to the highly number of combination.
1 Like
#2243
  1. Sha256
  2. because it would be pure guesswork, man. Possibly a lifetime of no sleep and still unlikely to get there.
1 Like
#2244

1. What is the hashing algorithm called used in Bitcoin?
SHA 256 (Secure Hashing Algorithm 256).
2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
The brute-force method means you have to pick a random input and then compare the output hash with the target hash and repeat until you find a match. For SHA 256 this would require an average of 1.7x10^38 attempts (which is a very large number).

1 Like
#2245
  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 takes way too long to complete.
1 Like
#2246

Q: What is the hashing algorithm called used in Bitcoin?
A: SHA 256 (Secure Hashing Algorithm 256).

Q: Why is this hashing algorithm really hard (almost impossible) to brute-force?
A: SHA 256 produces a 256-bit hash this is so large that it would take such an incredibly large amount of time to hash random inputs and compare the hash to find a match that it’s not worth worrying about!

1 Like
#2247
  1. SHA-256
  2. The amount of possibilities is to high to pull off a brute force attack.
1 Like
#2248
  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 you only have a chance to find the input of a hash function by trying random variables. This can take more than one life :stuck_out_tongue_closed_eyes:
1 Like
#2249

  1. SHA-256

  2. Because you would to keep trying random inputs until you get to the correct output and this would take too long to do

1 Like
#2250

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

Why is this hashing algorithm really hard (almost impossible) to brute-force?
“you have to pick up a random input, hash it and then compare the output with the target hash and
repeat until you find a match, it takes so long that it doesn’t matter.”

3 Likes