API Gateway

Question 1

Which of the following is typically NOT a responsibility of an API Gateway?

Accepted Answer

Business logic processing — An API Gateway should handle cross-cutting infrastructure concerns, not domain-specific business logic.

Question 2

An API gateway acts as…

Accepted Answer

A single routing entry point — It's the front door for an API/microservices system, receiving all requests and forwarding them to the right service.

Question 3

A key benefit of an API gateway in microservices is…

Accepted Answer

Hiding topology behind one endpoint — Clients call the gateway, not dozens of services directly; the gateway routes internally, decoupling clients from the service layout.

Question 4

Cross-cutting concerns commonly handled at the gateway include…

Accepted Answer

Auth, rate limiting, and TLS offloading — Centralizing auth, throttling, TLS, and observability at the gateway avoids duplicating them in every service.

Question 5

When an API gateway directs /users calls to the user-service and /orders calls to the order-service, that gateway function is called…

Accepted Answer

Routing by path, host, or headers — E.g. /users → user-service, /orders → order-service; the gateway maps incoming requests to backends.

Question 6

When the gateway fans out to three internal services and merges their results into one response for the client, this is called…

Accepted Answer

Combines results from multiple backend services — The gateway can fan out to several services and merge their responses, reducing client round-trips (a backend-for-frontend pattern).

Question 7

Putting authentication at the gateway means backend services can…

Accepted Answer

Skip re-implementing auth — Centralized auth means individual services focus on business logic, trusting the gateway's identity/authorization checks (often via passed tokens).

Question 8

A risk of the API gateway is that it can become…

Accepted Answer

A single point of failure — Since all traffic flows through it, the gateway must be replicated/scaled and monitored to avoid being a SPOF or bottleneck.

Question 9

SSL/TLS termination at the gateway…

Accepted Answer

Decrypts TLS at the gateway edge — Terminating TLS once at the gateway centralizes certificate management and offloads crypto from backend services.

Question 10

Rate limiting at the API gateway protects…

Accepted Answer

Downstream services from overload — Enforcing limits at the edge rejects abusive traffic before it reaches and overloads internal services.

API Gateway Architecture

Gateway or service?

Test your knowledge

Which of the following is typically NOT a responsibility of an API Gateway?

The short version

In more depth

API Gateway

Key Responsibilities

Interview Questions

References & Further Reading

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