An API gateway is a central point for managing all traffic to a set of APIs or microservices. In a typical API gateway deployment, all external (Internet) traffic is routed through the API gateway to internal APIs or microservices. This centralization provides a powerful mechanism to implement cross-cutting functionality required by all backend APIs or microservices such as authentication, rate limiting, and analytics.
- API gateways focus on routing external traffic to internal APIs or microservices ("North/South" traffic)
- API gateways implement cross-cutting functionality needed by all APIs or microservices
Today's cloud-native architectures consist of dozens or hundreds of microservices, many of which are exposed directly to the Internet. Giving end users a central point to access these microservices is critical:
- Consolidates common functionality into a central point, reducing duplication
- Provides a single point of access, simplifying end client architecture and improving security