# Ztunnel

This document provides an overview of the architecture and design decisions around Ztunnel, the node-proxy component in ambient mode.

## Background and motivation

Motivations to implement ztunnel generally came from two areas.

First, and most importantly, it serves as a means to implement the real goal: waypoints.

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  repeated APIResourceDiscovery resources = 2;

  // freshness marks whether a group version's discovery document is up to date.
  // "Current" indicates the discovery document was recently
  // refreshed. "Stale" indicates the discovery document could not
  // be retrieved and the returned discovery document may be
  // significantly out of date. Clients that require the latest

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      "Legal Entity" shall mean the union of the acting entity and all

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      "Licensor" shall mean the copyright owner or entity authorized by
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      "Legal Entity" shall mean the union of the acting entity and all

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# Architecture of Istiod

This document describes the high level architecture of the Istio control plane, Istiod.
Istiod is structured as a modular monolith, housing a wide range of functionality from certificate signing, proxy configuration (XDS), traditional Kubernetes controllers, and more.

## Proxy Configuration

	analysisCmd.PersistentFlags().BoolVar(&ignoreUnknown, "ignore-unknown", false,
		"Don't complain about un-parseable input documents, for cases where analyze should run only on k8s compliant inputs.")
	analysisCmd.PersistentFlags().StringVarP(&revisionSpecified, "revision", "", "default",
		"analyze a specific revision deployed.")
	return analysisCmd
}

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