All requests from client applications first reach the API gateway, which then forwards them to respective backend services. The API gateway acts as a facade to the backend services, allowing API providers to abstract API implementations and evolve backend architecture without impacting API consumers. The gateway enables consistent configuration of routing, security, throttling, caching, and observability. Specifically, the gateway acts as a facade to backend services by accepting API calls and routing them to appropriate back-ends. It verifies API keys and other credentials such as JWT tokens and certificates presented with requests. It enforces usage quotas and rate limits, and transforms requests and responses as specified in policy statements If configured, caches responses to improve response latency and minimize the load on backend services. Furthermore, the API gateway emits logs, metrics, and traces for monitoring, reporting, and troubleshooting.