Reading assignment: Hashing

Blockchain and Bitcoin 101
#4297

  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?
    The hashing algorithm is a one-way calculation. The number of possible outputs is huge, too many to calculate or store an example of them all with existing technology. Every attempt to get an output with a criteria is effectively random (unless it has already been tried), there are no clues as to what input is required to generate an output.

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#4298
  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 is unidirectional, that is, once the algorithm creates the hash, it cannot be reversed.
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#4299
  1. The hashing algorithm is called SHA-256
  2. Because there is a set target of difficulty for each hash between 0-256 it takes considerable amount of time and processing power using process of elimination to find the naunce in the block chain header before the block can be added to the chain.
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#4300

  1. What is the hashing algorithm called used in Bitcoin?
    It’s called SHA-256 (Secure Hash Algorithm 256-bit).

  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    The total number of possibilities is unfathomably big. There are 2^256 possibilities to find . This is more than atoms in the universe. SHA-256 cannot be reversed to original data, it is a cryptographic hash algorithm which verifies that data matches with what is expected.

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#4301
  1. Sha-256
  2. The computational power needed to solve te SHA-256 hash. The possibilities are almost endless with 2^256 possible outcomes… It would take far too long it becomes impractical… (talking lifetimes.)
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#4302

1.SHA-256
2. A brute - force attack would need to make 2 ^256 attempts to generate the initial data.

2 Likes
#4303

  1. SHA-256

  2. Because it will take an enormous amount of computational power and an enormous amount of time to solve the hash problem if one were to use brute force.

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#4305
  1. SHA-256 is the algorythm used in Bitcoin.
  2. SHA-256 can not be reverted with the current technlogy: it’s not possible to calculate the input
    (incremented header’s value) from the output (a hash value smaller than the target). In order to get
    the required output you have to try over and over again by increamenting the header’s value an by
    applying the hash algorythm to it every time till you get an hash smaller than the target.
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#4306
  1. SHA-256
  2. Because it is nearly impossible to find the inout based on the output
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#4307

Sha-256
It is impossible to find the input based on the output

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#4308
  1. What is the hashing algorithm called used in Bitcoin?
    SHA-256 algorithm.
  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    THe algorithm only goes one way. So returning from the output to the input is impossible. It is like putting componentis in a blender, at the beginning you know what they are, but once blended, you cannot recover the original components as such.
2 Likes
#4309

  1. The hashing algorithm used in Bitcoin is SHA-256

  2. It is really hard, because of the amount of computational power used to solve increasingly difficult mathematical equations in the proof-of-work (PoW) function, adding new blocks to the blockchain in exchange for newly created Bitcoin. The hashing algorithms can only be solved to find the ultimate hash output, they can not be reversed to calculate the initial raw data.

2 Likes
#4310

  1. SHA-256

  2. SHA-256 is 2 to the power of 256 possibilities making it almost impossible to brute-force due to its unidirectional movement with mathematical computations being so large that time is not on a person’s side to solve.

2 Likes
#4311
  1. SHA -256
  2. The possible outcomes are seemingly endless. It would take an enormous amount of computer power and time.
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#4312

Answer the questions below.

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

Bitcoin uses the Secure Hash Algorithm SHA-256

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

This hashing algorithm is really hard to brute-force due to its inherent features among which are the production of unique hashes (2^256 possibilities) and the fact that the algorithm can only be solved to obtain the final hash output, not done in reverse to obtain the initial raw input data.

2 Likes
#4313
  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?
      Bitcoin has algorithms can only be solved to find the ultimate hash output, they can not be reversed to calculate the initial raw data.
2 Likes
#4314
  1. What is the hashing algorithm called used in Bitcoin?
    Secure Hash Algorithm SHA -256
  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    Because it’s almost impossible to reverse the output of the function to get back the input.
2 Likes
#4315
  1. SHA- 256
  2. The cap of the unidirectional computation is so large that the odds of the same miner outputting identical hashes in his/her lifetime are infinitesimally small.
1 Like
#4316
  1. SHA 256
  2. If a hash is changed, it also changes all the previous hashes which makes it practically impossible to change once there are many transactions
1 Like
#4317
  1. SHA 256
  2. So may combinations to get back to input (as example with some ingredients grinded in a grinder).
1 Like