In a microservices architecture, a client might interact with more than one front-end service. Given this fact, how does a client know what endpoints to call? What happens when new services are introduced, or existing services are refactored? How do services handle SSL termination, authentication, and other concerns? An API gateway can help to address these challenges.
https://learn.microsoft.com/en-us/azure/architecture/microservices/design/gateway
