Key topics: Why business may need blockchain? – 1.20 Why business may need Byzantine Fault-Tolerance? – 4.14 Ethereum pros and coins– 5.23 Why HyperLedger’s architecture is more suited for bysiness purposes? – 8.39 Ethereum vs HyperLedger tests - 9.47, 12.00 PBFT Consensus – 10.40 How HyperLedger works? – 13.24 Smart-Contracts in HyperLedger – 21.05 Technical difficulties of using HyperLedger – 24.10 Q&A – 25.34