Reading assignment: Hashing

Blockchain and Bitcoin 101
#282

  1. SHA-256

  2. You give the hashing algorithm any input and you’ll receive back a 256 bit character string. It is almost impossible, in ones lifetime, to brute force the hash. What makes blockchain special is that each prior block, in the blockchain, has that block’s hash. So, if you change a prior block’s hash it changes all of the proceeding block hashes.

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#283

SHA-256

The time it would take to brute-force it is immense.

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#284

  1. The hashing algorithm for Bitcoin is called SHA-256 [Secure Hashing Algorithm].

  2. We know that even a SINGLE change in the input can result is an output [i.e. the hash] to be completely different. Since a hash is 64 characters long, imagine the number of attempts one would have to make to select a random input, hash it and then compare the output with the target hash. On an average, one would have to make 2^127 attempts,

2^127 means 2x2x2x2x2…127 times. This is an astronomical number of attempts. Not impossible but extremely unlikely.

#285
  1. The hashing algorithm used in Bitcoin is called Secure Hashing Algorithm 256 (SHA-256)
  2. This hashing algorithm is really hard (almost impossible) to brute-force, because there are so much possibilities to reverse engineer a certain Hash output to the correct input. In other words: It would take forever to guess the right input out of all the possible inputs, that it is not worth the effort, trying.
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#286

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

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

The number possibilities to brute for this computation with SHA256 it’s just not time feasible to ever get a match.

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#287

  1. SHA 256

  2. The output of a hash string has 2^256 possabilities meaning it’s allmost impossible to match a certain string of text as input with a fixed number as output. The possabilites are “endless”.

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#288

  1. What is the hashing algorithm called used in Bitcoin?
    Secure Hashing Algorithym 256, SHA-256

  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    Any change to the hashed algorithm will subsequently change all of the previous blocks’ information, which is impossible.

#289

The Bitcoin hashing algorithm is Secure Hashing Algorithm (SHA) 256 which means the hashes produced have 256 bits making them harder to brute-force than shorter outputs. To brute force this system to find the input could take up to 2^256-1 attempts (massive computational power over a long, long, long time) making it very hard to break.

#290
  1. SHA 256
  2. Because you would need to determine with as many as SQRT(2^256) instances to even have a 50% chance of success of brute force
#291

this question is about brute forcing Sha256 and not about the cryptographical link between bitcoin blocks.
It will take you an astronomical amount of time to guess the inputs of a certain hash. wich is almost impossible

#292

  1. Secure Hashing Algorithm 256, or SHA-256.

  2. There are 2^256 possible outputs so to find the a match currently takes too long to make the task feasible.

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#293
  1. SHA256
  2. Its hard to reverse the output of the function to get back the input.
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#294

  1. Sha-256

  2. It is impossible because guessing the input based on the 256 bit encrypted hash output.

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#295

1.SHA-256
2.Astronomical odds are against you when trying to guess the input.

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#296
  1. What is the hashing algorithm called used in Bitcoin?
  • SHA-256 (Secure Hashing Algorithm 256)
  1. Why is this hashing algorithm really hard (almost impossible) to brute-force?
  • The number of tries it takes to brute force is huge. So it takes to long that it doesn’t matter any more.
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#297

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?
Because (for now) the number of tries is too large to reverse compute the hash. Because there does not yet exist a quantum computer that can guess infinite solutions in a fourth dimension and return an output to us in our third dimension.

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#298
  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?
    Brute-force is continuously running computer calculations. The hash calculation solution can be found on any calculation from the first to the last, or any iteration along the way. Hashing calculation rates can be sped up or slowed down according to the block creation needs of the system. And, calculating the correct number could take up to four life-times to complete.
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#299

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 brute-force method basically means that 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.
To do this and break the pre-image resistance via brute force takes so long that it is not worth it

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#300
  1. the hasching algorithm used in Bitcoin is called SHA-256 (Secure Hashing Algorithm 256)
  2. with to bruce-force method it would take in an Average scenario 2^127 = 1.7 X 10^38 trys, which is a lot and in the end does´t matter.
#301
  1. Sha 256
  2. Because it would take an immense amount of computer power to find the input based on the output
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