API Gateway

An API gateway is a single entry point that sits in front of a set of backend services and routes each client request to the right one. Clients call one address instead of knowing about every microservice.

Gateways also handle shared concerns in one place: authentication, rate limiting, SSL termination, caching, request and response transformation, and logging. Examples include Amazon API Gateway, Azure API Management, Kong, Apigee and NGINX. A load balancer only spreads traffic across copies of a service; an API gateway understands APIs and routes by path, method and user.