Why do microservices need an API gateway?

A microservices API gateway is a crucial component in microservices architectures as it provides a unified entry point that simplifies complexity, enhances security, and boosts performance. By managing incoming requests and responses, an API gateway handles tasks such as rate limiting, access quota management, caching, and routing, preventing the exposure of internal concerns to external clients and adding a layer of security against malicious attacks. It supports various communication protocols, allowing for flexibility in integrating different services, and reduces the complexity of microservices by centralizing authentication and authorization. The use of an API gateway facilitates innovation by enabling microservice mocking and virtualization, thus supporting the evolution of architecture without impacting client-side operations. However, implementing a gateway requires careful orchestration, and choosing between options like open-source, cloud, or on-premise solutions depends on factors such as flexibility, cost, and regulatory requirements. The API gateway works in tandem with service meshes to provide holistic management and connectivity, indicating that both can be utilized based on a business's specific needs. Tyk is highlighted as a flexible and user-friendly option for managing API gateways in microservices environments.