Why: What is Bitcoin? How was it born?
How to build and query: Merkle Tree (Merkle tree) algorithm query (not for querying nodes, but for querying disordered nodes), new creation, update
Implementation:
System Video: Personal Space of Deep Blue Shuo Block_哔哩哔哩_Bilibili
Core Technology
- distributed storage
- consensus mechanism
- smart contract
- Cryptography
summary:
The blockchain is a product for the promotion of Bitcoin, which mainly solves the problem of people earning interest in the middleman during the transaction process. With Bitcoin, there are no middlemen, and complete transaction freedom is realized
The blockchain data structure is a blockchain table + hash tree. There are multiple blocks in the blockchain table, and each block stores a hash value. The hash tree is actually a binary tree + hash pointer, which stores specific transaction records.
When creating a hash tree, first hash the specific transaction records of each block to generate node(0,n), then perform hash splicing between every two nodes, and then hash to generate a parent node, and finally there will be a hash root node.
Data blocks L1, L2, L3, and L4 are hashed to generate hashL1-L4, then generate Hash0-1, and finally generate Top Hash.
Features of blockchain
Blockchain usage scenarios
Real-world applications of blockchain
Bidding: put the process on the chain to prevent corruption
Supply chain management: put the production, distribution, sales and other link data on the chain, and consumers can trace the source according to the QR code
Smart manufacturing: linking contract, manufacturing, supply and other links in series
Electronic contracts: guarantee that the contract will not be lost or re-signed
Automatic account distribution: distribute according to the agreed share of the matter, to prevent malicious fraud after the event is completed
Cross-border trade: Use distributed ledgers to quickly reach an agreement among all parties, reducing costs and increasing efficiency
People's livelihood
Drug Traceability: Preventing Counterfeit Drugs
Charity Tracker: How donated money is used
Medical care: electronic medical records, sharing medical records among hospitals