HTTP/2

In a monolithic architecture, components communicate via in-memory method calls, which are instantaneous and highly reliable. When moving to a microservices architecture, however, these components are separated by network boundaries. Communication becomes an out-of-process network call (Inter-Process Communication, or IPC). For years, REST (Representational State Transfer) over HTTP/1.1 with JSON payloads has been the default standard for building web APIs. While REST is excellent for public-facing web services and client-to-server interaction, it introduces significant bottlenecks when used for high-frequency, low-latency, internal service-to-service communication.