Chapter 26:Blockchain Databases Database System Concepts,7th Ed. @Silberschatz,Korth and Sudarshan See www.db-book.com for conditions on re-use
Database System Concepts, 7th Ed. ©Silberschatz, Korth and Sudarshan See www.db-book.com for conditions on re-use Chapter 26: Blockchain Databases
Outline ■Overview Blockchain Properties Achieving Blockchain Properties via Cryptographic Hash Functions Consensus Data Management in a Blockchain ■Smart Contracts Performance Enhancement Emerging Applications Database System Concepts-7th Edition 26.2 @Silberschatz,Korth and Sudarshan
Database System Concepts - 7 26.2 ©Silberschatz, Korth and Sudarshan th Edition Outline ▪ Overview ▪ Blockchain Properties ▪ Achieving Blockchain Properties via Cryptographic Hash Functions ▪ Consensus ▪ Data Management in a Blockchain ▪ Smart Contracts ▪ Performance Enhancement ▪ Emerging Applications
History Blockchain technology's development was driven initially by cryptocurrencies. But cryptocurrency is just one application of blockchain Cryptocurrencies: ·Purely online Maintained by a decentralized distributed ledger ■Bitcoin One of the first successful cryptocurrencies,and the best known. Published under the pseudonym Satoshi Nakomoto Aims to be an anonymous,fully distributed and decentralized currency There are other blockchains that are more appropriate for blockchain- based enterprise data Database System Concepts-7th Edition 26.3 ©Silberscha乜，Korth and Sudarshan
Database System Concepts - 7 26.3 ©Silberschatz, Korth and Sudarshan th Edition History ▪ Blockchain technology’s development was driven initially by cryptocurrencies. • But cryptocurrency is just one application of blockchain ▪ Cryptocurrencies: • Purely online • Maintained by a decentralized distributed ledger ▪ Bitcoin • One of the first successful cryptocurrencies, and the best known. • Published under the pseudonym Satoshi Nakomoto • Aims to be an anonymous, fully distributed and decentralized currency • There are other blockchains that are more appropriate for blockchainbased enterprise data
Types of Blockchain ■Public Anyone can download the needed software and create a blockchain node No trust assumed among participating nodes Permissioned Permission to run a blockchain node is granted by a permissioning authority Some degree of relaxation of the assumptions of trustlessness and autonomy The type of blockchain influences the choice of algorithm used by which nodes agree on the next block to be added to the blockchain Database System Concepts-7th Edition 26.4 ©Silberscha乜，Korth and Sudarshan
Database System Concepts - 7 26.4 ©Silberschatz, Korth and Sudarshan th Edition Types of Blockchain ▪ Public • Anyone can download the needed software and create a blockchain node • No trust assumed among participating nodes ▪ Permissioned • Permission to run a blockchain node is granted by a permissioning authority • Some degree of relaxation of the assumptions of trustlessness and autonomy ▪ The type of blockchain influences the choice of algorithm used by which nodes agree on the next block to be added to the blockchain
Blockchain Properties and Structure Linked list of blocks Each block contains a pointer to the previous block plus a hash of the previous block Except,of course,for the first block,called the genesis block Tamper resistance The inclusion of the hash of the previous block makes tampering difficult Changing the contents of a block means changes all newer blocks as well Specific mathematical requirements for the hash function (see later) Replication prevents replacement of the entire blockchain without gaining majority control Database System Concepts-7th Edition 26.5 ©Silberscha乜，Korth and Sudarshan
Database System Concepts - 7 26.5 ©Silberschatz, Korth and Sudarshan th Edition Blockchain Properties and Structure ▪ Linked list of blocks • Each block contains a pointer to the previous block plus a hash of the previous block ▪ Except, of course, for the first block, called the genesis block ▪ Tamper resistance • The inclusion of the hash of the previous block makes tampering difficult ▪ Changing the contents of a block means changes all newer blocks as well • Specific mathematical requirements for the hash function (see later) • Replication prevents replacement of the entire blockchain without gaining majority control