Service Mesh
In plain terms
An infrastructure layer that manages service-to-service communication.
Going deeper
A service mesh (like Istio) handles routing, retries, encryption, and observability between microservices via sidecar proxies, so application code doesn't have to. It centralizes networking concerns.
Under the hood
Splits a control plane (policy/config) from a data plane (sidecar proxies); adds powerful traffic control and mTLS but real latency and operational complexity.
Examples
Istio, Linkerd, Consul Connect, Envoy proxies, mutual TLS between services.
Think of it like...
Like a city's road system with traffic lights and toll booths managing how every building communicates, so the buildings don't each hire their own traffic cops.