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Ethereum
blockchain app platform
Blockchain
★ Addresses (Accounts)
○ createKey() -> (privateKey, pubKey)
○ verifySignature(pubKey, makeSignature(privateKey, data)) -> True
★ Blocks
○ Every ~15s
○ Transactions
○ Prevent double spending
○ Mining
■ Difficulty
■ hash(serialized(transactions)+nonce) -> N bits, 00000....difficulty...101011011101
■ rewards coins
■ limited supply of coins
○ P2P (every node has the full blockchain containing the history of all transactions)
■ Simplified wallet apps which only have private key for making transaction, delegating
transaction processing to blockchain access service provider
Bitcoin
★ Limited transaction language
Ethereum
★ smart contracts
○ pay transaction and computation with ethers
○ apps with state stored on blockchain
○ solidity - looks like javascript, turing complete transaction language
○ ethereum virtual machine (EVM)
○ mining epoch (GPU, no ASIC)
○ apps
■ alternative cryptocurrences
■ dapps
Ethereum
★ pros-cons of transaction languages
★ DAOs
★ market capitalization
○ btc: $~9B $600/btc
○ eth: $~0.9B $11/eth
Demo
★ Geth
★ Ethereum wallet
★ Mining pool, etherminer on GPU
★ Create, use contract
Q/A

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Ethereum @ descon 2016

  • 2. Blockchain ★ Addresses (Accounts) ○ createKey() -> (privateKey, pubKey) ○ verifySignature(pubKey, makeSignature(privateKey, data)) -> True ★ Blocks ○ Every ~15s ○ Transactions ○ Prevent double spending ○ Mining ■ Difficulty ■ hash(serialized(transactions)+nonce) -> N bits, 00000....difficulty...101011011101 ■ rewards coins ■ limited supply of coins ○ P2P (every node has the full blockchain containing the history of all transactions) ■ Simplified wallet apps which only have private key for making transaction, delegating transaction processing to blockchain access service provider
  • 4. Ethereum ★ smart contracts ○ pay transaction and computation with ethers ○ apps with state stored on blockchain ○ solidity - looks like javascript, turing complete transaction language ○ ethereum virtual machine (EVM) ○ mining epoch (GPU, no ASIC) ○ apps ■ alternative cryptocurrences ■ dapps
  • 5. Ethereum ★ pros-cons of transaction languages ★ DAOs ★ market capitalization ○ btc: $~9B $600/btc ○ eth: $~0.9B $11/eth
  • 6. Demo ★ Geth ★ Ethereum wallet ★ Mining pool, etherminer on GPU ★ Create, use contract
  • 7. Q/A