BUILDING ON BLOCKCHAIN II JOSIAH YAHAYA

Types of Blockchains 1. Public Blockchain 2. Private Blockchain 3. Consortium Blockchain 4. Hybrid Blockchain

Public Blockchain A public blockchain is a non-restrictive, permission-less distributed ledger system. Anyone who has access to the internet can sign in on a blockchain platform to become an authorized node and be a part of the blockchain network. Examples: 1. Bitcoin 2. Ethereum 3. Binance Smart Chain

Private Blockchain A private blockchain is a restrictive or permission blockchain operative only in a closed network. Private blockchains are usually used within an organization or enterprises where only selected members are participants of a blockchain network. Examples: 1. Multichain and Hyperledger projects (Fabric, Sawtooth) 2. Corda

Consortium Blockchain A consortium blockchain is a semi-decentralized type where more than one organization manages a blockchain network. This is contrary to what we saw in a private blockchain, which is managed by only a single organization. Examples: 1. Energy Web Foundation 2. R3

Hybrid Blockchain A hybrid blockchain is a combination of the private and public blockchain. It uses the features of both types of blockchains that is one can have a private permission-based system as well as a public permission-less system. Examples: 1. Dragonchain

Ethereum Ethereum is a decentralized platform powered by open-source blockchain technology with smart contract functionality. It is most popularly known for its cryptocurrency, ether (ETH) but it also hosts countless decentralised applications.

Ethereum Vs Bitcoin Ethereum Bitcoin Ethereum can be considered more efficient simply because it hosts an electronic and programmable network with a variety of applications. The bitcoin blockchain was created solely for the bitcoin cryptocurrency. ETH has no limited supply, although the time invested to mine one block does put a limit to how much ether can be mined in a year. Bitcoin has a limited supply. There can be at max 21 million bitcoins in the world. Ethereum used PoW initially, but as of 2018, it has moved on to Proof-Of-Stake. Bitcoin uses PoW solely to create new blocks.

Consensus Protocols 1. Proof-Of-Work (PoW) 2. Proof–Of-Stake (PoS) 3. Delegated Proof-Of-Stake(DPoS) 4. Leased Proof-Of-Stake (LPoS) 5. Proof Of Elapsed Time (PoET) 6. Practical Byzantine Fault Tolerance (PBFT)

Creating smart contracts 1. Setting up local blockchain 2. Understanding Metamask 3. Using Remix 4. Writing a simple smart contract 5. Deploying smart contract to testnet