blockchain and cryptocurrency

public blockchain

• anyone can write to it

• every node has a copy of the blockchain

• best security and trust between peers

• openness has made some companies nervous

private blockchain

• controversial in their existence

• controlled network of nodes

• mining is easier as less competition

• ideal for regulated industries

database vs blockchain

• blockchain:

  • is decentralized system consisting of many mining nodes

  • each node contains a copy of the blockchain

  • data becomes immutable once enetered into a block

  • each node competes to solve the hashing puzzle

• database

  • fast storage

  • high performance

  • data can be updated or deleted as necessary

  • replication across databases is easy

  • easier to manage and maintain

Which aspect of blockchain involves solving a complex mathematical puzzle with proof of work when calculating the block address needed to add a block to a blockchain?

block mining

What are the two common options for implementing a blockchain?

hyperledger and ethereum

blockchain

distributed database that is shared among the nodes of a computer network

smart contracts

programs stored on a blockchain that run when predetermined conditions are met; they typically are used to automate the execution of an agreement so that all participants can be immediately certain of the outcome, without an intermediary’s involvement or time loss

Which combination of ciphers and keys is used in bitcoin mining?

Elliptic curve ciphers (ECC), 256-bit private key, 512-bit public key

There are different parts involved in Bitcoin transactions. Which part of the transaction involves the Bitcoin receiver sending their public key to the sender, and the sender then uses their private key to create a signature for the transaction, and also adds a public key?

The IN element of the Bitcoin transaction involves the receiver sending a public key to the sender, and the sender then uses their private key to create a signature for the transaction, and also adds a public key.

genesis record

the first transaction created in bitcoin

public blockchain

a type of blockchain bitcoin transactions where all the transactions are viewable

private blockchain

a type of blockchain bitcoin transactions that takes place within a private space where all the transactions are restricted to only the concerned parties

gas

the unit used in ethereum to measure the amount of work that is required to perform a single Keccak-256 hash

hashing

• easy to compute the hash value

• infeasible to generate a message that has a given hash

• infeasible to modify a message without changing the hash

• infeasible to find two different messages with the same hash

Which combination of cryptographic algorithms are used in hash functions?

MD5 and SHA are the two most common hashing methods used in hash functions.

Hashed Message Authentication Codes (HMAC)

specific type of message authentication code involving a cryptographic hash function and a secret cryptographic key