This document discusses Istio, an open platform for connecting, managing, and securing microservices. It provides features like circuit breaking, fault injection, canary deployments, rate limiting, service metrics, tracing, and mutual TLS without requiring code changes. Istio uses interceptors and Mixer to enforce policies across traffic in a Kubernetes cluster. The document outlines some capabilities of Istio and also notes it is still in alpha stage with some known issues around documentation and debugging.