A ledger is a record of changes. A node is a computer participating in the network. Consensus lets participating nodes coordinate a shared history under stated rules and failure assumptions. Start with the disagreement the record must resolve, rather than choosing a fashionable protocol.
Our fictional Harbour dispatch group contains a supplier, a carrier, a warehouse and a buyer. They share dispatch authorizations for individual crates.
Their training ledger starts with crate C7 available. A dispatch request changes available to allocated.
Two competing requests cannot both consume the same available crate. This is an orderingEstablishing the sequence in which requests are considered or recorded.
Example: R1 precedes R2 in the paper sequence. problem with a simple business consequence: two teams could act on different allocations. All case facts and observations in this course are invented for practice.
Apply the supplied facts
Harbour receives request R1 allocating C7 to route North and request R2 allocating C7 to route South. Each assumes C7 is available.
Write the disagreement and one outcome the shared record must produce. Record your response in worksheet section problem.
Model response and reasoning
The record must choose one effective allocation of C7 and show the competing request as unsuccessful.
Both requests consume the same starting availability. Accepting both would contradict the supplied rule, even if both were signed.
Check: Name C7, the conflicting allocations and the single-allocation condition.
Source
Blockchain Technology Overview. The exercise inputs and model choices are fictional teaching examples.