Authentication
Authentication checks who a person or service is. It's often shortened to AuthN.
Another example
A passkey proves who a returning account owner is before starting a new session.
Main parts
- 01Identity or input
- 02Policy or transformation
- 03Stored result and audit evidence
Use it when
Use secure flows with rate limits and recovery. Add multi-factor options when the risk calls for them.
Do not use it when
Never invent your own password storage or reveal whether a sensitive account exists.
Name used in code
WebAuthn / OAuth / OIDC Before you ship
Check contracts and invariants, authorization, and input limits. Test retries, one-time effects, timeouts, and partial failures. Verify data integrity, compatibility, monitoring, recovery, and rollback.
Outcome: Design or review Authentication for this system while keeping data correct, secure, and easy to operate. User context: A passkey proves who a returning account owner is before starting a new session. Technical concept or control: Authentication. Why it fits: Use secure flows with rate limits and recovery. Add multi-factor options when the risk calls for them. Do not use it when: Never invent your own password storage or reveal whether a sensitive account exists. 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): No single official standard controls the whole term. Its meaning may change across teams, platforms, or frameworks. 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.
Check this request
Review the current use of Authentication. Definition: Authentication checks who a person or service is. It's often shortened to AuthN. Release checks: Check contracts and invariants, authorization, and input limits. Test retries, one-time effects, timeouts, and partial failures. Verify data integrity, compatibility, monitoring, recovery, and rollback. Before changing code, report the evidence you found, gaps, severity, and the smallest safe fix.