Reading assignment: Hashing

Blockchain and Bitcoin 101
#604
  1. SHA-256
  2. To crack the hashing algorith output you need the right input. The problem is that a 256-bit hash has so many different possibilities that trying to find the right input is infeasible.
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#605

  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 one would have to guess every single input, this would take a lot of time. But if we have quantum computers it will become easy.

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#606

Sha256
There are an impractically large amount of possibilities to try. And every slight variation gives a unique hash.

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#607

  1. SHA 256

  2. The possible inputs are so large that it would take forever to solve.

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#608
  1. SHA-256
  2. In order to determine the original value of a hash output the only way to determine the input is to enter a random input and compared the output hash of the random input with the output hash of the value you are trying to determine. Due to the fact every hash input has a unique output hash (in other words the algorithm is collision resistant) and small changes to the input hash provides drastically a different output hash, it would take an incredibly long amount of time to brute-force the algorithm because the input pool is just so large and there are so many different posibilities.
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#609

Hello,
1) The hashing algorithm used in bitcoin is SHA-256. which refers to taking a string of inputs, no matter the length, and having an output of a fixed length. in this particular case 256 bits.
2) The SHA-256 hashing algorithm is almost impossible to brute-force simple because the amount of time it would take to find the corresponding hash is astronomical, making it moot

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#610

1: SHA 256

2: The hashing algorithm is really hard to brute-force in part due to the time it would likely take.

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#611

  1. Sha 256 is the hashing algorithm used for bitcoin.

  2. The amount of time taken to brute-force it is infeasible.

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#612
  1. Its called SHA-256
  2. Because of the possibilities of combinations. It´s wether economic nor time effective.
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#613
  1. What is the hashing algorithm called used in Bitcoin?
    • SHA256
  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    • Large search space. For a 256bit hash, average search time would require about (2^256)/2 times.
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#614
  • What is the hashing algorithm called used in Bitcoin?
    SHA-256
  • Why is this hashing algorithm really hard (almost impossible) to brute-force?
    It is infeasible. You can only brute force to determine the original input.
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#615

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 extremely random. There are x# of possibilities based, it would be extremely hard to pinpoint the correct one. Even a small change in the data would result in a complete different hash value. The sheer amount of time it would take to brute-force and the level of specificity involved makes it almost impossible.

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#616
  1. SHA256
  2. It is a one way encryption algorithm that produces an output of constant length regardless of the input, making it pre-image resistant.
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#617

  1. SHA-256

  2. First of all, what makes it possible to brute-force SHA-256 is that it is deterministic. But because of the many input possibility of SHA-256, it is practically not possible, because it takes so much time.

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#618

1: SHA-256
2: Even small changes in the input changes the hash dramatically and used in Blockchain will affect all blocks

#619
  1. What is the hashing algorithm called used in Bitcoin?

SHA-256 or Secure Hashing Algorithm 256.

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

The brute-force method which requires you to randomly select an input, hash it, and compare the output with the target hash takes a VERY long time when dealing with a 256 bit hash. As the article puts it, you can spend every second of the rest of your life trying this method with just a 128 bit hash and you likely would not come close at all.

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#620
  • What is the hashing algorithm called used in Bitcoin? Sha256
  • Why is this hashing algorithm really hard (almost impossible) to brute-force? Probability is infinitely small and computation of trial and error would simply take too long to be meaningful.
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#621

  1. What is the hashing algorithm called used in Bitcoin?
    SHA-256 for Secure Hashing Algorithm of 256 bits

  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    It takes an excessive amount of time to go through all the input possibilities to find the one that would results in the same output.

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#622
  1. SHA-256
  2. The number of possibilities is so immense that it would take too much time, effort and cost.
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#623
  1. Sha 256
  2. It’s nearly impossible to figure out the input based on the output.
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