Reading assignment: Hashing

Blockchain and Bitcoin 101
#1508
  1. Bitcoin uses SHA - 256 (Secure Hashing Algorithm - 256)
  2. The hashing algorithm involves taking an input string of any length and using the algorithm to convert data to a fixed length output. Basically, regardless of the size of input data, the output will always have a fixed length of 256 bits. This hashing process makes it infeasible to determine the input based on the output hash. Although not impossible, it is extremely unlikely as the only way to find original input is through the “brute force method”. This involves picking a random input, hash it and compare the output with target hash. The odds, however, of achieving that with a 256 bit hash are massive.
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#1509

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
every single changing of input change the HASHE drastically. 2 in 256… possibilities

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#1510
  1. SHA 256
  2. toomany guessesrequired
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#1511
  1. SHA 256
  2. The number of possible unique values is 2 to the power of 256 thus impossible to predict the output. It’s like correctly predicting 256 coin tosses in a row
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#1512

What is the hashing algorithm called used in Bitcoin?
SHA-256 (Secure Hashing Algorithm 256)

Why is this hashing algorithm really hard (almost impossible) to brute-force?
Because the amount of numbers you need to guess is so large that it would take really long even for super fast computers to guess.

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#1513 
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?
   As it’s has so many combinations, and to test out (brute force) two 64 characters string  it’s impossible, at least with today's computer technology as it’s takes so long time many many years.
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#1514

  1. What is the hashing algorithm called used in Bitcoin?
    BTC hash algorithm is SHA-256

  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    because it will take a long time

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#1515

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

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

  3. SHA256

  4. Due to its extremely high min entropy that it is extremely infeasible (almost impossible) to brute force.

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#1516

1: Bitcoin uses the SHA 256 hashing algorithm

2: To brute-force the algo, you’d need to pick the solution from 2^256 combinations, and do it before a new block is added… computationally infeasable.

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#1517
  1. SHA-256
  2. Because of the colossal number of possibilities is very huge and it will take a large amount of time or possibly it will even consume your whole life trying, so at the end of the day its impractical.
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#1518
  1. The Bitcoin hashing algorithm is SHA-256 (secure hashing algorithm-256)
  2. Brute force is almost imposible as a result of 256 bits.
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#1519

  1. What is the hashing algorithm called used in Bitcoin?
    R: The hashing algorithm used in Bitcoin is SHA-256

  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    R: Brut forcing this algorithm would be really hard because if only one small thing is changed in the hashed content the hashing code is changed. This means creating random content then hashing it and comparing the two hash codes would take really long time and the hashed content could be outdated when it was guessed.

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#1520

SHA-256 is the secure hashing algorithm currently used in bitcoin.

Hashing is a mathematical function (algorithm) used to generate value(s) from a string of text, any length input to generate a fixed-length output; each input has only one output. In other words, hashing is a one-way function, meaning inserting a unique input (like a fingerprint) will generate a unique output, but an output cannot generate an input (in the case being discussed). Because the input is unique, any change to the input would generate a different unique output.

Bitcoin’s (cryptographic) hash function is a special class of hash functions which has various properties to ensure it is secure, make it ideal for cryptography These properties a cryptographic hash function needs are:
(1) Deterministic - a unique input generates the same output (hashes) every time.
(2) Quick Computation - should be capable of returning the hash of input quickly; fast process = efficiency.
(3) Pre-Image Resistance - property of a hash function making it computationally infeasible to find an input that maps to an output hash; hard to invert.
(4) Small Changes In The Input Changes the Hash - any change to input generates a different unique output hash.
(5) Collision Resistant - infeasible for two different inputs to generate the same output hash.
(6) Puzzle Friendly - algorithm will not show any pre-determinable correlation between input X and output Y; in a function such as H(K // X) = Y if K is chosen from a distribution with high minentropy, then it is infeasible to find X such that H(K // X) = Y

“brute force” is nothing more than “random guesses” under these conditions

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#1521

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

Why is this hashing algorithm really hard (almost impossible) to brute-force?
The number of possible hashvalues is so large that it is practically impossible
to brute force.

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#1522

1.The hashing algorithm used in bitcoin is SHA 256.

2 . The hash value is so long that it would take several lifetimes to guess.

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#1523

  1. SHA 256

  2. With brute-force you end up having to pick inputs at random, hash it and then compare. This becomes time consuming. Finding a match can take a lot of time.

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#1524

  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? - Huge computational possibilities due to the 256 bits and potentially e.g. the puzzle friendly with high entropy (large distribution values) makes the probable time to break the security a very very very long time and may not be worth the effort. Additionally, collision resistance is more probable than pre-image resistance with high entropy.

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#1527
  • What is the hashing algorithm called used in Bitcoin? SHA-256
  • Why is this hashing algorithm really hard (almost impossible) to brute-force? It uses mathematical equation so difficult that it is infeasible but not impossible to change the computation.
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#1528

  1. SHA 256

  2. Because SHA 256 hash has 2^256 different possibilities. It would simply take too long to find a collision for any brain or computer existing today (that will maybe change in the future with f.e. Q-computing!?).

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#1529

*Bitcoin uses sha-256
*hashing is one way computation, is not possible (infeasible) to get the source data from a hash result.

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