Reading assignment: Hashing

Blockchain and Bitcoin 101
#4659
  1. SHA-256
  2. Because each input has it’s own unique hash
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#4660
  1. Secure Hash Algorithm or SHA-256
  2. To successfully mine and verify a new block, a computer must solve a series increasingly difficult hashes to arrive at a number that is equal or less than the target block’s header. This target number can be anywhere between 1-256, and if the computation for any given hash is wrong, software must start once again from scratch in order to hopefully arrive at a “winning” number. This is similar to winning a lottery.
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#4661
  1. It’s called SHA-256 (Secure Hash Algorithm)
  2. Due to large computation involved in the possible input to match the hash.
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#4662
  1. SHA-256
  2. In order for a miner to solve the algorithm, they need to take the hash of the block with the nonce, arbitrary values, hash it again, and compare results with the difficulty level. If their results are below the difficulty level, it is accepted and the new block is appended to the blockchain. If not, they take the hash again and repeat the process with a new nonce each time until the results are less than the difficulty level.

There is a specified hash rate for each block to be mined to maintain a specific and predictable supply of Bitcoin. Miners are have an incentive to mine more or less as the difficulty level rises or decreases.

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#4663

  1. It is called the SHA-256

  2. Hashing Algorithms can be used to get an output, but the same algorithm cannot be reserved to get the input of the same output. ( I hope this is clear as mud).

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#4664

1 - SHA-256
2 - because of the the number of tries it would require to find the input that generated the output

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#4665
  1. SHA-256
  2. A hash is a cryptographic result of the BTC hashing algorithm which is solved in a linear, unidirectional manner. It does not allow reversal to calculate raw data.
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#4666

SHA 256
The hash algorithm is a universal translator for computers= receiving any types of data’s from letters to digits or even large media files (such as images) and translates these data’s into alphanumeric strings of different sizes. Sizes will depend according to hashes functions. (Usually 64 bit, 128 bit or 256 bit)
One way only
Every algorithm has specific features Bitcoin hash algorithms can only be solved to find the ultimate hash’s output, it can’t be reversed to calculate the initial input.
This one way only is made possible thanks to interlaced maths equations which do not allow the reversal. This hash makes it therefore almost impossible to force.

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#4667
  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 Input is converted in to a 256 byte encrypted hash. Even though output hash remains the same for input, it is practically impossible to guess the input based on the hash value as its 256 bytes.
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#4668

  1. Secured Hash Algorithm (SHA-256)

  2. The hashing algorithm is hard to brute force because the length of data is very long, it is also hard to get the input from the output, so this has to occur by random chance. The results can only be added if it is below the difficulty level, and the block will be added. If not, the machine will take the hash again and do it over and over again with a new nonce until it achieve a result less than the difficulty level

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#4669

Bitcoin’s blockchain uses SHA-256 to run it’s consensus mechanism. (Secure Hash Algorithm)

This hashing algorithm is almost impossible to brute-force. Although the possibilities are not endless, the number is so large (on avg 2^256 guesses), it’s outside of anything we’ve ever dealt with. In order to mine a block, the block’s header needs to be hashed linking it to the next block and so fourth. Hackers would be playing a constant game of catch up in that they would have to change the hash for each block and new blocks are added every 10 minutes.

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#4670

  1. SHA-256 (Secure Hash Algorithm).

  2. The hashing process in mining is considered a lottery as each hash provides a random number between 0 and 256. So the trial and error process of getting a hash value below the target makes it almost impossible to brute force as it isn’t based on the amount of work done.

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#4671
  1. sha-256.
  2. Because it’s almost impossible to know the input based on the output
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#4672
  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?
    -there are to many possibility’s which makes it not practical
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#4673
  1. SHA-256.
  2. Because you’d need to find an input that gives the same output. Discovering an input through an output in this scenario is nigh-impossible, so your computer has to attempt a myriad of different inputs to get a right answer (A.K.A guessing).
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#4674

sha-256
The total possibilities are so large that two parties are extremely unlikely to achieve the same result

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#4675

  1. SHA-256

  2. It is a 256 digit number that cannot be reversed to calculate the initial data.

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#4676

  1. Bitcoin uses the SHA-256 hashing algorithm.

  2. There are 2^256 potential SHA-256 hashes - a larger number than the number of atoms in the visible universe.

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#4677
  1. What is the hashing algorithm called used in Bitcoin?

Bitcoin uses a Secure Hash Algorithm (SHA) named “SHA-256”.

  1. **Why is this hashing algorithm really hard (almost impossible) to brute-force? Because it requires consensus among a large number of nodes, which is very difficult to do. Also, any if transaction is changed, every following transaction in the database will also need to be changed. This is a very difficult task. Additionally, the BTC algorithm produces new hashes, but cannot be used to calculate the original data which was changed by the hash function.
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#4678

Also, mining is considered a lottery because rewards are not based on work done. Each hash provides a random number between zero and a maximum 256 digit value.