Reading assignment: Hashing

Blockchain and Bitcoin 101
#744

1.SHA-256

  1. In order to breach the Bitcoin SHA-256 security you need to perform a break collision. This means that you need to find 2 different INPUTS into the hashing algorithm which result in the same output pattern. This can only be performed by guessing. The probability of a successful guess in a 256 bits hashing algorithm is a total of 2^256. That is approximately 1 X 10^77 =
    1 in 100000000000000000000000000000000000000000000000000000000000000000000000000000.
#745
  1. SHA256
  2. Would simply take more than a lifetime to guess correctly.
#746

  1. The hashing algorithm use in bitcoin is sha-256.

  2. It is possible to break the pre-image resistance via the brute force method but it takes so long it doesn’t matter.

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#747

  1. It is SHA 256 - Produces a 256-bit hash.

  2. You have to use “brute-force method” that means 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. Which can take forever to do that.

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#748

  1. Sha 256

  2. the sheer amount of random combinations of 256bit hashes makes it highly improbable to randomly get the right one.Each guess is like trying to fill a swimming pool with one rain drop at a time, its so insignificantly small it doesn’t make a difference.

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#749
  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 number of computational possibilities is so high with a 256 hash that it would take several lifetimes to solve, making it infeasible.

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#750
  1. Secure Hashing Algorithm 256
  2. It is nearly impossible since the time to do make a right guess may take so long time (we are talking almost until the end of time) that it is not even worth trying.
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#751

  1. SHA 256

  2. Because guessing an input from a hash is like guessing one out of an immensily large number. Almost impossible.

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#752

  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 the time to guess that exact number is so random and that it would take several generations to make the right guess, time that is not available and makes it not feasible.

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#753

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

  • Why is this hashing algorithm really hard (almost impossible) to brute-force? Its is infeasible to figure out the input data based on the output hash due to concatenation and time constraints of the block time.

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#754

Thank you for clarifying. I intend to rewatch all the lectures and solidify these concepts as this is all very new to me.
cheers

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#755
  1. The hashing algorithm used in Bitcoin is called SHA-256
  2. The hashing algorithm is infeasible to solve through brute-force because the possibilities of hashes are 2^128. It is a 128-bit hash.
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#756
  1. Sha256
  2. Because you can’t go from output to the input. It’s physically impossible!
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#757
  1. bitcoin uses the sha 256 hashing algorithm which takes any input and always give an output of 256 bytes in length/
    2 it is difficult to brute force because it is essentially guessing and it requires alot of computing power to even attempt this which has a real world cost and can not be done without this problem and take forever.
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#758
  1. sha256
  2. the possibility of finding the input based on the out put
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#759
  1. Bitcoin uses SHA-256
  2. SHA-256 algorithm is almost impossible to brute-force because the probability of guessing the original input takes an impossible amount of time. A quantum computer would be necessary.
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#760
  1. SHA 256 PoW
  2. Thanks to the puzzle friendly property, it would take 2^256 in the worst case scenario to crack it. Suppose we have an output value (Y). If (k) is choosen randomly from a distribution with high-min entropy it is infeasible to find an input (x). Not impossible but it would take longer than the age of the universe. Its safe x)
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#761
  1. SHA-256
  2. It takes very long time to guess the input based on the output
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#762

1.SHA 256
2.Because you would have to guess correctly a string of letters and numbers in upper or lowercase that was 256 characters long without a single character being wrong. Even if you chose the correct letter in the correct place it would still have to be either lower or upper case.

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#763

  1. Secure hashing algorithm 256 (SHA - 256)

  2. Because it will take so long that it doesn’t matter.

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