service mesh
also: service-to-service mesh, microservices mesh
A service mesh is a dedicated infrastructure layer that manages communication between microservices in containerized applications, handling routing, security, and observability without changing application code.
A service mesh uses sidecar proxies deployed alongside each microservice to intercept and manage all network traffic between services. This decouples networking logic from application code, allowing operators to enforce policies consistently across services.
Common implementations include Istio and Linkerd. A service mesh provides features like automatic load balancing, circuit breaking, retry logic, and mutual TLS encryption between services.
Example: In a Kubernetes cluster running multiple microservices, a service mesh automatically encrypts communication between services, routes traffic based on rules, and collects metrics—all without requiring changes to the application itself.