Cryptographic Hashing

Outcome: Design or review Cryptographic Hashing for this system while keeping data correct, secure, and easy to operate. User context: Before installing a downloaded file, an engineer compares its SHA-256 fingerprint with one published through a trusted channel. They must match. Passwords need a special salted password-hashing or key-derivation function, because plain SHA-256 is not enough. Technical concept or control: Cryptographic Hashing. Why it fits: Use this term for data-integrity fingerprints, content addresses, or security methods that require a cryptographic hash. Do not use it when: Do not call hashing encryption, promise that fingerprints are always unique, or store passwords with a fast general hash. Engineering requirements: Define inputs, outputs, contracts, and rules that must always hold. Set authorization and input checks. Define failures, timeouts, retries, one-time effects, data moves, and compatibility limits. Operations: Add useful signals and logs that hide sensitive data. Set capacity limits and write an operator guide. Test recovery and rollback. Acceptance criteria: Contract and failure-path tests pass. Data and authorization rules still hold during retries and partial failures. Check performance limits, monitoring, recovery, and rollback. Evidence and limits (evidence boundary): The standard covers only the listed scope. It does not choose the visual style, product decision, or Vibulary example. Unknowns to confirm: Where the code runs, data stores, traffic shape, consistency needs, and the security boundary. Also confirm the compatibility period, service goals, and rollback limits.