perAPIkey

perAPIkey is a governance approach in API management that applies usage policies and access controls at the level of individual API keys. By tying limits and permissions to a specific key, providers can tailor access to different customers, applications, or plans and monitor activity on a per-key basis.

Core features include per-key rate limits (requests per minute or hour), quotas for a time window, and scoped permissions that restrict which endpoints or data a key can access. Many implementations provide per-key analytics, alerts for anomalies, and automated revocation or suspension of a key if a policy is violated.

Implementation typically occurs at an API gateway, reverse proxy, or service mesh. A central policy store defines rules per key; requests are audited and counters incremented, with limits checked before routing. Dynamic policy changes and key rotation support are common, reducing redeployment needs.

Security and privacy considerations include protecting keys in transit and at rest, using HTTPS, avoiding embedding keys in client-side code, following least-privilege principles, rotating keys regularly, and maintaining audit logs for compliance and abuse detection.

Use cases include multi-tenant SaaS, partner integrations, tiered pricing, and abuse mitigation. perAPIkey governance enables fair use, revenue optimization, and precise audience targeting by enabling different limits and permissions per customer or application.

Limitations include added operational complexity, potential performance overhead, and the need for robust key lifecycle management. Key leakage, policy drift, and propagation delays across regions must be managed through careful design and monitoring.

See also: API key, rate limiting, quota management, API gateway.