I'm aiming at applying an api pattern as can be described for instance on https://medium.com/design-microservices-architecture-with-patterns/api-gateway-pattern-8ed0ddfce9df
As it mentions, "since API Gateway handle client request in centralized placed, its best practice to implement cross cutting functionality on the API Gateways" such as authentication and authorization.
I'm wondering about MITM attacks.
We can make sure microservices are only called by the gateway when whitelisting only the gateway IP, that would be a network safety. But I think this network-level protection shouldn't exclude application-level protection. Only another security at application level (mutual TLS?) would protect the microservices from MITM attacks.
So as a conclusion for a most-perfectly-safe application platform, is api offloading pattern really recommended? And if mitm is a real risk then what's best to add to the pattern to make it real safe?