Reading assignment: Hashing

Blockchain and Bitcoin 101
#1247
  • The hashing algorithm used in Bitcoin is called SHA-256.
  • It is almost impossible to brute-force because it would take forever to guess the input that was required for the function to produce the hash, due to the length of the input and the amount of possibilities to try.
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#1248

What is the hashing algorithm called used in Bitcoin?

the algorithm used in bitcoin is called SHA-256.

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

The reason why its infeasible to brute force the algorithm is because its too time consuming and more luck than most of has is needed to do it in a timely fashion.

#1249

  1. SHA-256 (Secure Hashing Algorithm 256)

  2. Infeasible to find 2, that generating same output in form of hash function. The process can take very very long time.

#1250
  1. SHA 256
  2. The probability is so small of finding the inputs that would result in a collision
#1251
  1. SHA 256
  2. If you are dealing with a lot of data, it could take a very large, impractical number of tries before you determine the original input from the hash value.
#1252

1.) SHA256
2.) In order to brute-force you would need to backwards match a text character to its SHA256 Hash. Given the number of possible characters, scripts, languages, numbers, cases, symbols, emojis, :dizzy_face: etc… combinations one would have to just guess. The number of guesses possible are so many that it would take a lifetime, or a quantum computer, to make all the guesses possible fast enough to solve just the one hash and then changing that hash would change all the other hashes immediately notifying the ledger that something had changed, or was being attempted to be changed.

#1253
  1. SHA-256
  2. This algorithm is almousy impossible to brute force becouse input data lenght is that same as out put data lenght and you can’t find 2 inputs to produce the same out put in a hash function.
#1254
  1. SHA 256
  2. the algorithm is almost impossible to brute force due the low probability of finding the input to recreate the same hash output has an average probability of 2^127. The computational force required to “guess” the correct input in a timely manner would be greater than is currently possible. There is no known way to deduce the input from the output.
#1255

Hashing

  1. SHA-256
  2. To randomly guess/brute force the input/algorithm is just impractical and unrealistic with the current computational power.
#1256

What is the hasshing algorithm called used in bitcoin?
SHA 256
Why is this hashing algorithm really hard (almost impossible) to brute force?
Beacause of the hash pointer inside each block which makes it impossible to brute force.

#1257

  1. SHA-256

  2. Firstly, the hash changes completely with even the smallest change of the input data. Secondly, there are so many combinations that it is infeasible to brute force. Pre-image resistance, there are 2^127 different combinations, which is ridiculously secure since it would be so time consuming to find the right combination.

#1258

  1. SHA 256

  2. It is super hard to find the input value by only knowing the output with this algorithm. Unless some breakthrough technology comes about then it would take many lifetimes to brute force

#1259
  1. SHA-256
  2. It is infeasible for someone to deduce the input from the output using the brute force method because SHA-256 has 2^256.
#1260

1.- SHA-256
2.- Because in order to find the input you will need to try and compare your information between 1 and 2^128 – 1 times to brute force it and find the input.

#1261

The hashing algorithm is called Sha256.

Reverse engineering the Hashed 256 bit output of the function is virtually impossible, due to the only way being that you would have to repeatedly guess randomly, which would take dozens of lifetimes if you spent each life making one guess every second.

#1262

1. What is the hashing algorithm called used in Bitcoin?
It’s called sha 256

2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
It is infeasible to brute-force because it is:
1) Deterministic
Same output for same input
2) Pre-Image Resistance
it is infeasible (not impossible but very hard) to determine the original input from its hash value
3) Puzzle Friendly
*For every output “Y”, if k is chosen from a distribution with high min-entropy it is infeasible to find an input x such that H(k|x) = Y. *
Suppose you have an output value “Y”. If you choose a random value “k” from a wide distribution, it is infeasible to find a value x such that the hash of the concatenation of k and x will give the output Y.

#1263

[quote=“ivan, post:1, topic:8422, full:true”]
Answer the questions below.

  1. What is the hashing algorithm called used in Bitcoin?
    The hashing algorithm used in Bitcoin is called SHA-256.
  2. Why is this hashing algorithm really hard (almost impossible) to brute-force?
    This hashing algorithm is almost impossible to brute-force because given the supercomputers now available that can process 200 quadrillion computations per second. There are 3.1536B seconds in 100 years. That gives the number of computations on the order of 10^26. So, given that 256-bit data has 2^128 possibilities, that is 3.4x10^38, you can see that it’s not a fruitful endeavor.
#1264

  1. SHA-256

  2. A small change in the input will have a massive change in the hash output. This means that to brute-force you have to randomly give an input and then compare it to the output hash. with the amount of possible outputs this process is so time consuming it is almost impossible to do.

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#1265

sha-256

it would take a lifetime to figure out the possibilities 2^256

#1266
  1. Sha 256 is the hashing algorithm
  2. This algorithm is very impossible to brute force it is very to find 2 inputs in the data to produce the same output in a hash function.