Reading assignment: Hashing

Blockchain and Bitcoin 101
#684
  1. SHA-256
  2. There are too many options. This makes it almost impossible to find 2 inputs using brute force.
    2^256 different possibilities
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#685

  1. SHA-256

  2. Because of pre-image resistance and high-min entropy

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#686
  1. Bitcoin uses SHA-256 as it’s hashing algorithm.
  2. It’s pre-image resistance is very high. It’s infeasible that it can be broken/hacked (not impossible but highly unlikely). The average chance of it being hacked means hacker would have to run the “brute force method” 1.7 X 10^38 times to even maybe be successful so it’s impractical.
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#687

1)SHA 256
2) No matter how large or small the input, the generated output is the same fixed length of output. This combined with the complexity of the output make it Pre-image resistant i.e. it is infeasible that one would be highly able to determine the original input without sustained high computing power spanning several lifetimes (i.e. based on current available computing technology)

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#688

  1. SHA256

  2. Because there are too many possibilities to just random guess a human and it would take 3+ lifetimes to go through all the possible options trying 24 a day. Plus the output is Pre-Image resistant, meaning you cant tell from the output what the input would have been.

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#689
  1. Bitcoin uses SHA-256
  2. SHA-256 is so hard to brute force because of how long (multiple lifetimes) it would take to attempt to randomly guess match hash outputs to the respective inputs to break the “pre-image resistance.”
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#690

  1. SHA-256

  2. So many variables and 1 small change creates such massive change.

#691
  1. BTC use SHA-256 secure hashing algoritm
  2. The variable lenght input gives always a 256 bit lenght output . In thes algoritm is impossible to get the same output for two different inputs .
#692

It is called SHA(Secure Hash Algorithm)-256 in short SHA-256

Cause he would take too long time thanks to his structure, requires too many tries to force.

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#693
  1. SHA 256 (256 Bits)
  2. Because the likelihood to get the right hash is 2^128 - 1
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#694
  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?

It would take a very long time to do it because there are 2^256 possibilities and you would have to be unbelievably lucky to get the answer quickly. Most likely it would take lifetimes to do it making the process less efficient.

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#695
  1. The hashing algorithm in bitcoin is called SHA-256
  2. The hashing algorithm is really hard (almost impossible) to brute-force because of the almost infinite possible inputs to then find the output.
4 Likes
#696
  1. What is the hashing algorithm called used in Bitcoin?

Secure Hashing Algorithm 256 - SHA-256

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

The hashing algorithm is hard to brute force due to pre-image resistance. The only way to break the hash is to guess the input. Due to the vastly large amount of point values that exist within the function, trying to find the perfect match of input and point value to equal your output is mathematically infeasible.

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#697

  1. SHA-256 (Secure Hashing Algorithm 256)

  2. It has Pre-Image Resistance. Given H(A) it is infeasible to determine A,where A is the input and H(A)
    is the output hash.

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#698
  1. SHA - 256 ( Secure Hashing Algorithm 256)

2.It contains Pre-Image resistance. Given H(A) it is infeasible to determine A, where A is the input and H(A) is the output hash.

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#699

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?

It is unlikely someone would find the 2 inputs that mach the output in the hash function.

#700

  1. SHA-256

  2. a) It is almost impossible to reconstruct the initial data from the hash value. A brute-force attack would need to make 2^ 256 attempts to generate the initial data.
    b) Having two messages with the same hash value (called a collision) is extremely unlikely. With 2^ 256 possible hash values (more than the number of atoms in the known universe), the likelihood of two being the same is infinitesimally, unimaginably small.
    c) A minor change to the original data alters the hash value so much that it’s not apparent the new hash value is derived from similar data; this is known as the avalanche effect.

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#701
  1. SHA-256
  2. Because it defines the difficulty target. If it was easy there would be more collisions and orphaned blocks.
#702

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

  2. This hashing algorithm is really hard (Infeasible) to brute-force because of the average time it takes to randomly pick up random inputs, hash it, compare to outputs, and repeat until you find a match. This process will basically take more than a lifetime (on average).

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#703
  1. SHA256
  2. only Chuck Norris could do that because he is richer than the whole world and immortal:)