Homework on Hash Functions - Questions

Blockchain and Bitcoin 101
#4339

  1. Describe hash functions with your own words
    Hash functions are very complex computations that contain 1 unique input that will produce 1 unique output and are 1 way or linear. you can never go from output to input.

  2. How are hash functions used in cryptocurrencies like bitcoin? (Try to research this on your own, we will cover this later in the course but challenge yourself and see if you can find information on this already now).
    Hash functions are used for security, timestamp , and verification

  3. What does it mean when we say that hash functions need to be collision resistant? (We didn’t use the term “collision resistant” in the lecture, but you will easily find this on Google, we add this question intentionally to make you research information on your own, that’s how you learn best).

Collision resistant means there can only be 1 input for 1 output

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#4340

  1. Hash functions are mathematical sequences which are so complex that they cannot be reverse engineered. They transform any type of data into unique, alpha-numeric number sequences which act as a method for verifying that the original data hasn’t been manipulated after being pushed through the hash function.

  2. All transactions are turned into hashes so that the record is preserved. Then these hashes are inputed into the next block with the next transaction thus compounding the secure preservation of information that was inputed.

  3. Collision resistant means that two different inputs entered into a hash function won’t produce the same output.

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#4341
  1. Hash functions give data a unique digital fingerprint. You cannot get the input of the hash function from the output, as it would break the concept.
  2. It ensures that the mining of bitcoin is spread out over a period of time, and not all bitcoin are mined at once. It is also used for writing new transactions into the block chain.
  3. Collision resistant => When a hash function is collision resistant, it means it is very hard to find two inputs with the same output.
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#4342

1.) In Hash-Functions you create a Unique Output of a Unique Input. Its a one-way-function, you can only go from Input to Output, but you cant go from Output to Input. Its like a digital fingerprint. There are many Hash-Functions, SHA256 is the one that bitcoin uses.

2.) In Bitcoin, Hash-Functions are part of the Block-Hashing-Algorithm. The Inputs for the function are all of the most recent not yet confirmed transactions. There are also additional Inputs related to timestamp and informations of the previous block. Than the Miners start to hash this whole information to a Hash that starts with a certain numbers of Zero. This can take a lot of time to solve the block.

3.) Collision Resistant means that you cant Hash two different Inputs that create the same Output.

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#4343

  1. It is an irreversibel relation between input and output.

  2. It is used through miners to create new transactions into the blockchain

  3. A function is Collision resistance when different inputs have very low chance to share the same output.

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#4344
  1. A Hash function is the action of taking and input strand of any length and putting out an output of fixed length. For example, a transaction can be used as an input which is run through a hashing algorithm, which gives an output of a fixed length.
  2. In cryptocurrency like Bitcoin, it uses the Secure Hash Algorithm called SHA-256. In this case, be it big or small input, the output will always have a fixed 256-bits length. This is extremely important when dealing with a huge amount of data and transactions. This can be understood as if you have the Hash (output) you automatically can keep track, regardless the input size, volume, etc,.
  3. It means that it is practically impossible to find two inputs that hash to the same output.
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#4345

1.) Hash functions are part of the block hashing algorithm. They take an input of arbitrary size and perform a very complex series of mathematical operations on them, culminating in an alphanumeric base-16 output of fixed size (256 bits in the case of Bitcoin). Because of the complexity of these operations, it is impossible to deduce anything about the original input from the hash output.

2.) In Bitcoin, hash functions are used to allow miners to write new transactions into the blockchain. The hash function takes as input all recent transactions that have yet to be confirmed, as well as a time stamp and a connection to the previous block. Their output is a digital fingerprint of their input, in the form of a 256-bit alphanumeric base-16 hash.

3.) When we say that hash functions need to be collision-resistant, we mean that it needs to be difficult for the function to find two different inputs that produce the same hash.

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#4346
  1. Hash functions are one way functions for which each input produces a different and unique output. It is not possible to deduce the input from the output. That’s why they are one way
    2.The hash function is used to calculate a public address from the private keys
    3.Collision resistance is the property of a hash function that it is computationally infeasible to find two colliding inputs.
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#4347

  1. A hash is a mathematical algorithm that guarantees the integrity of a file.

  2. Hash functions are used to write new transactions on the blockchain.

  3. A collision is an identical hash and making hashes that don’t resemble one another lest they are based on the same input is the resistance part of it.

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#4348

  1. The numeric strings wherein data is interpreted to code by mathematical algorithms/equations are called hashes. The algorithm produces the " hash."

  2. Hash functions produce the safety, security, and value of cryptocurrencies like bitcoin (according to Burniske and Tatar) are “concepts as a stake of hardware, software, operating systems (OS), applications and end users in relation to a personal computer.” Translated data as proof of work are chained and linked in blocks. The miners use proof of work to compete with one another for the privilege to add blocks of transactions to Bitcoin blockchain. Competition for financial reward keeps blockchain secure. The hash function codes are so large from sets of possible numbers that it is impossible to break the codes making blockchain currencies secure.

  3. Hash functions need to be collision resistant so that the blockchain is secure and safe from hacking.
    Collision resistance is a property of cryptographic hash functions where from the input of data to the output resulting from the proof of work does not have two answers, or there is not more inputs arriving to the same answer. Essentially, collision resistance means that it is extremely hard to discover the original data from the output arrived.

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#4349
  1. It’s a one way function where you can only go from inputs to outputs (not output back to input).
  2. Hash functions are used for PoW currencies in the mining operations
  3. Collision resistant means that no two different inputs will yield the same output.
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#4350

  1. Hash functions are functions that produce specific outputs for any given input. Any input changes, the output changes.

  2. They are used in mining. Miners need to use computational power to solve complicated hash functions, once they are solved and verified, the block is added to the chain, and the miners are rewards with BTC

  3. Collision resistance means the hash function cannot have two inputs that result in the same output. If this happens, the hash function is useless because transactions cannot be verified independently if two inputs result in same output.

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#4351
  1. Hash functions are a one way set of functions that produce a unique output. The direction cannot be reversed meaning that there is currently no way to deduce what inputs contributed to that unique output.
  2. Hash functions are used to write new transactions into the blockchain. Bitcoin uses the SHA-256 hash function. I don’t know if this is correct but I think of the hash function as the substance of the information like a cross between a message and instructions. The hash function makes everything else possible because of the integrity of the function and its irreversibility in the blockchain.
  3. Collision-free means that no two input hashes should map to the same output hash.
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#4352
  1. hash function is Mona Lisa portrait that you can never roll back and dismantle to chemical ingredients of paint, hours of work, humidity condition of the room or hall where it was painted in order to make two identical unique. You can always duplicate it and even cheat the best pro in art industry with that, but if it would have SHA-256 code since a moment of creation you would never be able to be successful to copy, unless you have a time machine)))
  2. hash functions are used in 2 areas
  • creation of address (The SHA-256 hash function is used up to 3 times in the address generation process)
  • Mining: Proof-of-Work ( Hashing is a key process in block creation. What’s more, it is also used in multiple steps, since the miner must associate the transactions with the block. To do this, use the hash function to create the Merkle tree)
  1. Collision resistance is important when you’re relying on hash functions to always map two inputs to two different values
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#4353

  1. Describe hash functions with your own words

  2. How are hash functions used in cryptocurrencies like bitcoin? (Try to research this on your own, we will cover this later in the course but challenge yourself and see if you can find information on this already now).

  3. What does it mean when we say that hash functions need to be collision resistant? (We didn’t use the term “collision resistant” in the lecture, but you will easily find this on Google, we add this question intentionally to make you research information on your own, that’s how you learn best).

  4. Hash function is a function that gives a unique output for every input. You can not go from the output to input.

  5. the hash in Bitcoin is being used by resolving complex mathematical equations and a block is added in the blockchain
    3.Collision resistant means that it is impossible for two different inputs to have the same output

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#4354
  1. Describe hash functions with your own words

A hash function is a unique data input which calculates a unique data output
calculated output data can not be used to calculate the inital input data, it is a one-way function.

  1. How are hash functions used in cryptocurrencies like bitcoin? (Try to research this on your own, we will cover this later in the course but challenge yourself and see if you can find information on this already now).

Hash functions in Bitcoin is used to make and verify new transactions added to the blockchain.
Hash functions are used in Bitcoin mining as it is a one-way function to maintain the collision resistant nature of bitcoin.

  1. What does it mean when we say that hash functions need to be collision resistant? (We didn’t use the term “collision resistant” in the lecture, but you will easily find this on Google, we add this question intentionally to make you research information on your own, that’s how you learn best).

Collision resistance means it is very hard or impossible to find different inputs which calculates into same outputs.

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#4355

  1. Hash functions keeps the information in the blockchain secure and safe. Its a cryptocraphic translater. Information you put in comes out as a digital code. You cant calculate it backwards to find out the input.

  2. Creating public and private keys. In the mini g process.

  3. It means that its hard to find two inputs that generates the same output.

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#4356
  1. Describe hash functions with your own words
    Hash Functions are the single (digit) symbols/numbers/letters that when combined in a series acts like a unique ‘fingerprint’ for each unique input that gives a unique output. It can go from input to output but NEVER the reverse. Bitcoin uses SHA 256 as its’ Hash Function as it is secure, unlike the insecure and therefore no-longer utilized , MD5. The MD5 is insecure because it has been hacked when someone figured out how to go from Output to Input.

2. How are hash functions used in cryptocurrencies like bitcoin? (Try to research this on your own, we will cover this later in the course but challenge yourself and see if you can find information on this already now).
Hash Functions are used in cryptocurrencies like bitcoin in that it can input some text and can hash it. It is represented by a certain base number ( like base 16 or base 54) and this base number makes the hash more secure. Bitcoin uses a hexadecimal (base 16). Hence, each input will produce the same output and thereby functions as a Data Integrity Check.
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3. What does it mean when we say that hash functions need to be collision resistant? (We didn’t use the term “collision resistant” in the lecture, but you will easily find this on Google, we add this question intentionally to make you research information on your own, that’s how you learn best).
Hash functions need to be collision resistant means that if something is broken, ti can go from output to input. Hence, to break the Bitcoin, it would have to go to the initial input. Also, In cryptography, collision resistance is a property of cryptographic hash functions: a hash function H is collision-resistant if it is hard to find two inputs that hash to the same output; that is, two inputs a and b where a ≠ b but H ( a ) = H ( b ).[1]:136 The pigeonhole principle means that any hash function with more inputs than outputs will necessarily have such collisions;[1]:136 the harder they are to find, the more cryptographically secure the hash function is.

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#4357

1. Describe hash functions with your own words
Hash Functions are the single (digit) symbols/numbers/letters that when combined in a series acts like a unique ‘fingerprint’ for each unique input that gives a unique output. It can go from input to output but NEVER the reverse. Bitcoin uses SHA 256 as its’ Hash Function as it is secure, unlike the insecure and therefore no-longer utilized , MD5. The MD5 is insecure because it has been hacked when someone figured out how to go from Output to Input.

2. How are hash functions used in cryptocurrencies like bitcoin? (Try to research this on your own, we will cover this later in the course but challenge yourself and see if you can find information on this already now) .
Hash Functions are used in cryptocurrencies like bitcoin in that it can input some text and can hash it. It is represented by a certain base number ( like base 16 or base 54) and this base number makes the hash more secure. Bitcoin uses a hexadecimal (base 16). Hence, each input will produce the same output and thereby functions as a Data Integrity Check.
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3. What does it mean when we say that hash functions need to be collision resistant? (We didn’t use the term “collision resistant” in the lecture, but you will easily find this on Google, we add this question intentionally to make you research information on your own, that’s how you learn best).
Hash functions need to be collision resistant means that if something is broken, ti can go from output to input. Hence, to break the Bitcoin, it would have to go to the initial input. Also, In cryptography, collision resistance is a property of cryptographic hash functions: a hash function H is collision-resistant if it is hard to find two inputs that hash to the same output; that is, two inputs a and b where a ≠ b but H ( a ) = H ( b ).[1]:136 The pigeonhole principle means that any hash function with more inputs than outputs will necessarily have such collisions;[1]:136 the harder they are to find, the more cryptographically secure the hash function is.

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#4358

  1. Hash Functions are the mathematical processes that takes a input data, performs a operation and retunes with a fixed data size.

  2. in Bitcoin hash functions are used between transactions in the creation of the digital signature. this hash functions keep the blockchain network immutable, unchangeable and secure.#

  3. Collision Resistance is a property of a hash function, means that you will not find two different inputs having the same outputs.

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