> For the complete documentation index, see [llms.txt](https://docs.ionos.com/cloud/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ionos.com/cloud/~/revisions/AMiYziCllTKB2y2lmONY/serverless/api-gateway/api-gateway-faq.md). # FAQs ### What is an API Gateway? An API Gateway is a centralized service that acts as an entry point for APIs, providing security, rate limiting, routing, and monitoring features. It helps ensure secure and efficient communication between clients and backend services. ### What are the key features of an API Gateway? Key API Gateway features include API traffic management, protocol translation, load balancing, and a developer portal. These features provide efficient management of incoming requests, seamless communication between clients and backend services, increased productivity, and a better experience for developers. ### How do API Gateways work? API Gateways act as a buffer between clients and backend services. They can perform various complex operations, such as authentication, authorization, request transformation, response aggregation, and more, simplifying the communication process for clients and backend services. By analyzing request paths and applying routing rules, API Gateways ensure incoming requests are directed to the appropriate backend service or microservice within the ecosystem, enabling efficient request handling. API Gateways analyze backend service responses before relaying them to clients, allowing for additional processing, transformation, and data aggregation to optimize the response format and content for client consumption. ### Is API Gateway a paid service? Yes, the price depends on the number of requests and data transfers. ### Can I use the API Gateway to monitor API performance? Yes, the API Gateway in IONOS offers monitoring and analytics features that enable users to track API usage, performance metrics, and error rates and gain insights to identify performance bottlenecks and optimize API performance. ### What should I do if an API request fails? Check if the API service is running in your environment. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.ionos.com/cloud/~/revisions/AMiYziCllTKB2y2lmONY/serverless/api-gateway/api-gateway-faq.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.