The anchor case
Every failure in this module, in one system, with people imprisoned on the output.
Post Office Horizon, Bates & Ors v Post Office Ltd (No 6: Horizon Issues) [2019] EWHC 3408 (QB). Read the Audit Store and transaction-correction-tool passages before you design any of this. It is not a technical text and it is the most persuasive document in this module.
The claimed integrity controls are exactly what a modern design review would applaud. Each transaction basket received a sequential number and a digital signature, such that "if the data in the basket were to change after the digital signature was generated, this would be apparent." Baskets were copied to an Audit Store where a further seal was applied. On paper: hash-chained, sealed, tamper-evident.
Given sequential numbering, per-basket digital signatures and a sealed audit store — what defeated it?
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