What is API Gateway Security?

API Gateway security applies authentication, authorization, rate limiting, and threat filtering at the first point where API traffic enters the system. The goal is to evaluate trust and limits before requests reach backend services.

A gateway can centralize token validation, mTLS, IP allowlists, WAF rules, JSON schema checks, bot filtering, and suspicious-traffic logging. That does not make backend services exempt from security; service-level authorization should still run even after a request passes the gateway.

Risks It Helps Control

Access attempts with invalid or expired tokens
Credential stuffing and automated login traffic
Excessive requests that consume capacity or increase cost
Unexpected payload formats and basic injection attempts
Sensitive endpoints accidentally exposed to the public

Implementation Notes

API Gateway, rate limiting, and OAuth2 should be designed together for consistent edge security. Gateway logs alone are not enough; service logs, correlation IDs, and alerting rules need to be connected to the same flow.

Security policy should vary by customer plan, endpoint sensitivity, and business impact. Applying one limit or one WAF rule to every endpoint can create both unnecessary blocks and uncovered risks.