Which component acts as a proxy to control access to a RESTful Web Service?

• A. A proxy for the web service to control access to it
• B. The web service API (definition file)
• C. The web service interface implementing the API
• D. The web service implementation itself

Answer: (A)

When you need to control who and how clients access a RESTful service, a proxy placed in front of the service acts as the gatekeeper. The API proxy receives requests, enforces security policies, authentication, authorization, rate limiting, and other controls, and then forwards the approved requests to the actual service. This setup lets you manage access and policies centrally without altering the backend implementation.

The web service API definition describes the contract and interface but doesn’t perform request handling or enforcement. The interface implementing the API contains the actual behavior of the API, but it’s behind the proxy and not responsible for controlling external access by itself. The web service implementation is the business logic that carries out the service’s work after a request has passed through the proxy.

So, the component that acts as the proxy to control access is the front-end API proxy.