Can you explain what is meant by API Gateway and how it functions in distributed system architecture?

API Gateway is a component in distributed system architecture that acts as a single entry point for all client requests to multiple microservices. It receives requests from clients, routes them to the appropriate services, aggregates the results, and returns a unified response.

Main functions of API Gateway:

• Authentication and authorization of requests
• Routing requests to the necessary microservices
• Data aggregation from multiple services
• Rate limiting
• Caching responses
• Logging and monitoring

This approach simplifies client interaction with the system, hiding the complexity of the internal architecture and increasing security and manageability.