What is API Gateway?
API Gateway Definition: A service or appliance managing and securing API calls by routing requests, enforcing policies, and controlling access to backend services.
Understanding API Gateway
An API Gateway serves as the traffic cop for all the application programming interfaces (APIs) in your environment, providing a single entry point that handles authentication, rate limiting, monitoring, and other critical security functions. This architectural pattern became essential as organizations moved from monolithic applications to microservices and API-driven architectures, where dozens or hundreds of services might be exposed. Without a gateway, each service would need to implement its own security controls, inevitably leading to inconsistencies and vulnerabilities. Modern API gateways go beyond basic proxying to provide sophisticated traffic management, request transformation, response caching, and analytics capabilities. They're particularly valuable for enforcing consistent security policies across all APIs regardless of how they were implemented or which teams developed them. Organizations typically deploy API gateways as part of a broader API management strategy that includes developer portals, lifecycle management tools, and monitoring capabilities.