Homework on Hash Functions - Questions

Blockchain and Bitcoin 101
#4019

  1. Describe hash functions with your own words
    Creates an output 0-256 from input that is linear and creates a unique Hash tht is impossible to reverse engineer to know the 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 to solve a problem… ie unique output where the 1st miner to solve wins the next distribution of BTC which is 1/2 every 4 years on avg

  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 resistance is a property of cryptographic hash functions : a hash function is collision resistant if it is hard to find two inputs that hash to the same output; that is, two inputs a and b such that H ( a) = H ( b ). Every hash function with more inputs than outputs will necessarily have collisions.

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#4020
  1. Hash functions are one way encryption of the value, a slightest change in the input value will generate a different output
  2. Bitcoin uses hash algorithm in its consensus mechanism, so to validate a transaction it nodes will check the hashed value and if it matches the previous hashed in the current chain it will be added in the block.
  3. Algorithm will be identified as collision resistant if the value of 2 distinct input will never be the same on its output/hashed value. No two distinct input should have same output.
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#4021
  1. Functions that cannot be inverse engineered and give unique results
  2. Hash functions are send to miners to validate blocks of transactions. Every block hash functions have parts of the previous block.
  3. It’s very hard (almost impossible) to find two inputs resulting in the same result.
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#4022

  1. Describe hash functions with your own words
    Hash functions are one-way functions that give you an output of a digital fingerprint for the input. The key to hash functions is that you can go from input to output, but you cannot reverse the function from output to input.

  2. How are hash functions used in cryptocurrencies like bitcoin?
    Cryptographic hash functions allow for the creation and implementation of private and public keys as well as further offspring of those two such as addresses and wallets. Hash functions and keys are what allow for transactions to work and be recorded as legitimate transactions recorded in the blockchain.

  3. What does it mean when we say that hash functions need to be collision-resistant?
    Hash functions that are collision resistant mean that it has a very low possibility / almost impossible chance of giving the same output for two different inputs. This is important because each input must have a unique output for the cryptography to be useful.

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#4023

  1. Describe hash functions with your own words.Is a digital fingerprint of any amount of input date. Output has defined length. Function is one way.

  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 function is used to hash blockchain block headers. Node with the fastest result under defined difficulty get bitcoin for newly mined block. Hash function is the cornerstone of consensus mechanism proof of work.

  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 resistance means that you are not able to find two different inputs with the same output.

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#4024

  1. Hash functions take an input and create an output “hash”. These are one way.

  2. Hash functions are used to create a one-way transaction or data input. They are also used in mining, so when someone mines bitcoin, it can not be reversed and be un-mined.

  3. Collision Resistant means that there aren’t two separate inputs that can equal the same output. It is important so that only one hash function can equal one output.

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#4025

1 Hash functions are translators of a specific input, which will be converted into a unique output that shall only be created with that specific input. Hashing functions must be non-reversible

2 Hash functions are part of block hashing algorithms, which are used to write new transactions into a blockchain. New blocks carry parts of the previous hash in order to make blockchain data unchangeable

3 Two different inputs shall only with extremely low chances create the same output

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#4026
  1. A hash function converts a data set, large or small into a unique encrypted alpha numeric key that can then be verified throughout the transactional history to ensure the data hasn’t been tampered with without the need of seeing or verifying the data itself.
  2. Hash functions are used in crypto for a few different applications. One example is how the sensitive personal data associated with a bitcoin wallet address is encrypted through a hash function to give us our unique alpha numeric wallet keys. Another example is how miners have to complete a hashing algorithm for a chance at being rewarded tokens for the completion of the algorithm.
  3. When a hash function is referred to as collision resistant it means that it is very hard to find two data set inputs that equal the same alpha numeric output.
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#4027

Hash functions compute input giving result which is an unique fingerprint of that input.
2.
Bitcoin uses hash algorithm SHA256 which generate random numbers in a way that requires a predictable amount of CPU effort.
3.
To be collision resistant means to be hard to find two inputs that hash to the same output.

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#4028

  1. Describe hash functions with your own words
    Hash functions are mathematical functions with special properties, which are: very complex, non reversible (you cant get to know the inuput value from the output value) and singular (1 input gets only 1 output)

  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).
    In bitcoin, hash functions are used to write transactions on a new block. Miners use the inputs and try to get a hash with the biggest amounts of zeros, which needs a huge computational work to process it. The one who gets more zeros is the miner that solves the block, and gets a reward for it.
    Something like this, but much more complicate

  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).
    They need to be collision resistant to avoid errors on the results.
    Collision resistant means that the function cant créate the same hash for 2 different inputs. If it wasnt collision resistant, you could have 1 output from 2 different inputs, therefore 1 of the functions could potentially dissapear.

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#4029

1 - Hash function is a mathematical algorithm that converts any input data to a hash that can be ah hexadecimal number. This hash is unique to each data input. If just a single coma or space is changed in the original data, the output hash will be different.

2 - Hash functions are used in the mining process that write new transaction in the blockchain.

3 - It is mathematically possible that two different inputs result in the same hash, called hash collision, however it is important that this possibility is very low creating collision resistance.

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#4030

  1. Hash functions are strings of data, which range could vary up to 256-bit.

  2. A hash function in bitcoin is the process of having an input to formulate specific output. A hash function chops up the input into small section of string so that the algorithm can find the output in a expeditiously manner.

  3. It means when an input is entered, the hash function will not produce the same exact output.

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#4031

  1. Hash function is a one way linear function that when a unique input is enter, it gives out an unique output.

  2. the Hash function used in cryptocurrencies like bitcoin is a 256 SHA ( Secure Hash Algorithm 256) using the alphanumerical charactoers of 0,1,2,3,4,5,6,7,8,9, a,b,c,d,e and f. with an unique input, it puts out an unique output and the out put of a hash can not be crack

  3. collision resistant mean that for every unique input there is only an unique output. only if the input a = input b that the output will be the same.

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#4032
  1. Hash function turns a piece of data into a digital finger print of the data
  2. Blockchain uses hashes and hashes of hashes to ensure that previous data has not been modified
  3. Collision resistance in hash function means that it is unfeasible to find which 2 inputs produce the same output hash.
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#4033
  1. Describe Hash Functions with your own words

It’s a type of function that goes just in one way and can not be reversed. Also hash functions permit just one result (output) for a specific original data (Input). This data can be digits, letters, media, etc. with different sizes and forms because all of them will be translated into a computing language that gives a specific alphanumeric code.

  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 are used in bitcoin to create a specific SHA-256 (Hash) with the transactions that are made. This hash has to have certain zeros at the beginning in order to be able to pack all the transactions into a block. After that the block has to be uploaded into the network to be verified for other miners. So hash functions are made to add new blocks into the network and they’re used to secure the network transactions by encrypting them.

  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).

It means that it is almost impossible to find two different inputs that give the same output. Also sirve like a proof that a hash it’s secure which means it’s extremely difficult to hack that hash function.

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#4034

A hash function works by giving an input of data which is converted to binary code and given an output which is a unique digital fingerprint. If anything is changed in the original input you will get a different output or a different unique digital fingerprint.

They are used in the process of mining, computers will try to find the correct input to match the unique digital output fingerprint – once this is done they computer that finds it will get the block reward.

Collision resistant means that it’s possible for 2 different inputs to = the same output but this is very unlikely.

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#4035

  1. Describe hash functions with your own words
    Is a function that when an input is plugged in an output is produced.

  2. How are hash functions used in cryptocurrencies like bitcoin?
    They are used to create a unique transaction that becomes data which becomes a hash that used to in mining.

  3. What does it mean when we say that hash functions need to be collision resistant?
    a resistant property of hash function that it is very unlikely to have the same output from the same two inputs.

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#4036

  1. Hash functions are used to create a theoretically unique fingerprint of a message so that one can tell if the message is altered from its original form. In short, any change in the original input will result in a drastically different output.

  2. Hash functions are used in the process of mining. In Proof of Work system, miners are the users or entities that facilitate the network’s operations by using their computers’ processing power to solve complex mathematical puzzles (hash functions) in order to validate and verify the authenticity of the transactions. This is done to add new transactional data in the form of blocks to the blockchain. Once this is achieved the miner which solves the function is rewarded with Bitcoin.

  3. Collision resistant means it is difficult to find two inputs that hash to the same output

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#4037

1Hash functions are a one way linear equation
2. They are used as a basis for making sure mining can’t be achieved easily or by anyone except miner. They are used to mine new transactions on the blockchain… due to the length of all of said outputs in the chain it is then extremely tough to run the numbers down to under 256
3 it means that it is almost impossible that 2 inputs can make the same output, and that outputs cant be reverse engineered

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#4038
  1. hash functions can not be reversed. It is a fingerprint.
  2. hash functions must be complex, It goes only one way, from input to output.
    3 collision resistant implies security. the more collision resistant the more secure they are.
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