Introduction to Bitcoin and Existing Concepts

• History

• Bitcoin As A State Transition System

• Mining

• Merkle Trees

• Alternative Blockchain Applications

• Scripting

Bitcoin As A State Transition System

APPLY(S,TX) -> S' or ERROR

APPLY({ Alice: $50, Bob: $50 },"send $20 from Alice to Bob") = { Alice: $30, Bob: $70 }

APPLY({ Alice: $50, Bob: $50 },"send $70 from Alice to Bob") = ERROR

密碼學貨幣的帳是一個狀態轉移系統

Ethereum

• Ethereum Accounts

• Messages and Transactions

• Ethereum State Transition Function

• Code Execution

• Blockchain and Mining

Ethereum Accounts

In Ethereum, the state is made up of objects called "accounts", with each account having a 20-byte address and state transitions being direct transfers of value and information between accounts. An Ethereum account contains four fields:

The nonce, a counter used to make sure each transaction can only be processed once
The account's current ether balance
The account's contract code, if present
The account's storage (empty by default)

Ethereum Accounts

externally owned accounts, controlled by private keys, andcontract accounts, controlled by their contract code. 

Ethereum Accounts

Note that "contracts" in Ethereum should not be seen as something that should be "fulfilled" or "complied with"; rather, they are more like "autonomous agents" that live inside of the Ethereum execution environment, always executing a specific piece of code when "poked" by a message or transaction, and having direct control over their own ether balance and their own key/value store to keep track of persistent variables.

Messages and Transactions

Applications

• Token Systems

• Financial derivatives

• Identity and Reputation Systems

• Decentralized File Storage

• Decentralized Autonomous Organizations

• Further Applications

應用有三類

Financial

和金融有關的

Semi-financial

和金融有點關的

Not Financial

和金融無關的

• sub-currencies
• financial derivatives
• hedging contracts
• savings wallets
• wills
• employment contracts

自動執行的困難計算問題懸賞

• online voting
• decentralized governance