Let’s understand this with a banking system example. You have microservices like customer service, account service, and transaction service. The service mesh will ensure secure and reliable communication between these services. It can handle encryption, authentication, and authorization for inter-service communication, making sure that only authorized services can communicate with each other. The API gateway can expose endpoints for clients to perform operations like creating a new account, transferring funds, or retrieving transaction history. It provides a single entry point for all these operations, abstracting the underlying microservices from the clients. Some of the functionality overlap but they are not the replacements to each other.