Demythifying Blockchain Terminology

About Blockchain:

• Two main public implementations of blockchain are bitcoin and ethereum. For enterprises and private networks the main two implementations are HyperledgerFabric (more info here) and Ethereum
  • Quorum: is an Ethereum-based distributed ledger protocol / platform that supports block chain transactions and contract privacy.
• Consortium: network consensus / multiple organizations maintaining the network. There is a consortium Leader in private blockchain which sets up the initial ether.
• Participants validate and store transactions.
  • Data is stored in a ledger, ledger can be updated only by network consensus. Accounts can vote only once.
    • Distributed consensus is not a new topic. Products like HDFS, MQ, ZooKeeper / Kafka, Elasticsearch, etc already have implemented this form of data integrity. This approach addresses teh following challenges:
      • Crash Fault Tolerance (CFT) algorithms
      • Byzantine Fault Tolerance -BFT- (plus Practical BFT)
      • Impossibility Triangle (Consistency Availability Partition Tolerenace -CAP- Theorem
      • Distributed Consensus Algorithm:
        • ZooKeeper uses the Paxos Algorithm.
        • R3 Corda and HyperLedger Fabric use the Raft algorithm, now moving to BFT.
• Everyone in the network has an individual identical copy.

• After a contract is mined (think like deployed and instantiated), you can interact with it.
  • «Gas» is what miners are paid for transactions.
  • MetaMask: chrome extension to transfer ether between accounts.
  • Bitcoin transactions are monetary, in Ethereum is executable code as well.
• Blockchain forms a chain between two blocks using hashes (similar to a single linked list, where first node is called «genesis block» and «root node» in a linked list)

• Distributed Applications (DAPPs): development and deployment approach in blockchain as per below images.

• There are different types of clients for blockchain networks including full nodes, light nodes, and remote clients.
  • Ligth nodes don’t download the full blockchain, only the headers to validate the authenticity of the transactions.
  • The minimal setup is one transaction node (full node) and 2 validators (light node).

About Dev Tools:

• To build smart contracts the following languages are mainly used: Solidity for Ethereum, Kotlin for Corda and Go for Hyperledger Fabric.
  • There are other alternatives to Solidity, e.g.: serpent, viper. Soidity is also supported by Bitcoin.
  • These languages compile to ethereum bytecode to run in ethereum nodes
• There are many tools for Smart Contract development, incl.:
  • Truffle: set of tools to build, test and assist in smart contract and Dapp development.
  • TestRPC: in memory blockchain.
  • Ganache/Infura: personal ethereum blockchain to develop locally.
  • Hyperledger Besu is a popular Ethereum client
  • Remix: testing, debugging and deploying of smart contracts in the browser.
• There are many libraries to interact with an ethereum network, incl.: web3js, nethereum, truffle, etc

About Smart Contract Development

• Contracts have data and methods
• Contrats can interact with people and people between people
• Any participant of the network can call contract functions and change state as per example below.

Thanks for reading,

Javier Caceres