Cryptography II
Decentralization
dapp, decentralized app
https://www.blockaid.io
Blockchain
https://etherscan.io https://goerli.etherscan.io
OpenZeppelin
Think of blockchains as a ledger or record book
A proof of ledger even
Immutable ledger
So BTC would be proof of payment
Distributed P2P network
Byzantine Fault Tolerance
consensus protocol
orphaned blocks
Cryptocurrency
Ecosystem includes: nodes, miners, mines, mining pools
proof-of-work (POW), used by BTC
proof-of-stake (POS), used by ETH (or currently at POW and plans to move to POS)
field programmable gate arrays (FPGAs)
ICO initial coin offering
- Bitcoin can process about 7 tps (transaction per second)
- Ethereum can process aorund 15-30 tps
- PayPal’s tps is 193
- Visa is 1,700 tps
So scalability is an issue
Bitcoin (BTC)
first cryptocurrency
invented by Satoshi Nakamoto, released in around 2008
limited supply of 21 million coins
Bitcoin’s Monetary Policy - halving, block frequency
Ethreum (ETH)
focuses on smart contracts
Ethereum 2.0 was built to reduce energy consumption and increase transaction speed
Ether.js
Hardhat, development environment, deployment tool
Polygon / Matic Network
https://polygonscan.com
MATIC
Finality variant ensures that once a transaction is confirmed, it cannot be altered or reversed
Others
- Solana (SOL)
- Ripple (XRP)
- Cardano (ADA)
- Dogecoin (DOGE)
- USD Coin (USDC), stablecoin, always worth $1
Polygon can compete and complement Ethereum
Non-Fungible Token (NFT)
“People Are Spending Millions of Dollars on Loot for Games That Don’t Exist”
https://mintofdestiny.xyz
ERC-721, this means each token is unique, represents different assets with distinct values
OpenSea
NFT is just a digital asset
NFTs are unique and not interchangeable
Think collectibles, art, etc. Any unique item where each token has a different identifier and metadata
Smart Contracts
Solidity
Libra
Tokenization
real world assets (RWAs)
apparently BlackRock and Fidelity (along with startups like Tzero, Securitize, and Polymath) are using blockchaint to tokenize assets
physical asset oracle problem / blockchain oracle problem
“If Alice tokenizes her car, and Bob buys the token; how can Bob be sure he will receive the car?”
Fungible
ERC-20
Fungible tokens are identical and interchangeable
Versatile
ERC-1155
Supports both non-fungible and fungible tokens within the same contract
A single contract to handle multiple token types
Think games
Mining
To mine, you need: hardware, software, wallet (hardware or software)
CPUs vs GPUs vs ASICs (application-specific integrated circuit)
Nonce
Golden nonce
Nonce range
Picking transactions
Mempools
Wallets
MetaMask
good for ETH
cybersecurity
crypto
]