A practical starting point.
Use an API firewall review to decide which request properties can be evaluated before expensive or sensitive work begins. Allowed methods, accepted content types, bounded bodies, and endpoint-specific resource policies are useful starting points. The important question is not what a control is called, but which decision it can make reliably.
Validate the contract
Define supported methods, fields, types, and sizes. Decide how unknown properties and unsupported versions should be handled.
Bound expensive work
Separate request rate, concurrent work, payload size, and total consumption. Match the boundary to the resource being protected.
Roll out deliberately
Review representative would-be denials before enabling a new blocking rule. Keep a versioned policy and a narrow rollback path.
Turn the concept into a review.
Locate the decision
Map client, gateway, application, and worker responsibilities. Do not assume the gateway is the only route into the application or that internal callers need no checks.
Protect legitimate clients
Define retry behavior, cancellation, queue limits, and error handling. Explain how well-behaved clients can recover without duplicating costly operations.
Review exceptions
Temporary allow rules should have a responsible owner, an explicit scope, and a review date. Observe whether a rule blocks the intended behavior without silently creating another bypass.
Questions worth asking.
Does an API firewall replace a WAF?
Not automatically. Product capabilities overlap and vary. Compare the decisions each control can enforce in your architecture rather than relying on a category label.
Should every route have the same rate limit?
Usually the resource review should distinguish cheap reads from expensive exports, searches, or jobs. Validate any proposed thresholds using representative authorized traffic and capacity tests.
Go deeper in the journal.
API firewall vs WAF: choose the right control for the request
Understand where request filtering helps, what belongs in application authorization, and how to evaluate a layered deployment.
API rate limiting: protect capacity without breaking good clients
Move beyond one global request limit with endpoint budgets, bounded queues, and observable retry behavior.
API security checklist: build a stronger first line of defense
A practical path from endpoint inventory to access controls, resource limits, and a release process your team can repeat.