• Unit 8: Reaching Consensus

    Bitcoin transactions are signed, broadcast to the network, determined to be valid or invalid by nodes, and via the mining process, join the blockchain. This system is very carefully crafted to prevent fraud on the network without a central authority. How does a decentralized system decide who's transactions are valid? What happens if the same Bitcoin is sent to different people at the same time? How does the network come to an agreement on conflicting data? How is this process updated or changed? These questions are answered in this unit as you'll learn more about the mining process and the details of how consensus is achieved and maintained. 

    Completing this unit should take you approximately 3 hours.

    • 8.1: Elements of Valid Transactions

    • 8.2: The Mining Process

    • 8.3: Consensus

    • 8.4: Updating Consensus

    • 8.5: Exercise: Create a Valid Transaction via Your Testnet Node

    • Study Session Video Review

    • Unit 8 Assessment

      • Receive a grade