# 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

-p:before{content:"\f231"}.fa-pinterest-square:before{content:"\f0d3"}.fa-pizza-slice:before{content:"\f818"}.fa-place-of-worship:before{content:"\f67f"}.fa-plane:before{content:"\f072"}.fa-plane-arrival:before{content:"\f5af"}.fa-plane-departure:before{content:"\f5b0"}.fa-play:before{content:"\f04b"}.fa-play-circle:before{content:"\f144"}.fa-playstation:before{content:"\f3df"}.fa-plug:before{content:"\f1e6"}.fa-plus:before{content:"\f067"}.fa-plus-circle:before{content:"\f055"}.fa-plus-square:b...

        }

        if (!hasBeenPackagedDuringThisSession(project)) {
            // fallback to loose class files only if artifacts haven't been packaged yet
            // and only for plain old jars. Not war files, not ear files, not anything else.
            return determineBuildOutputDirectoryForArtifact(project, artifact);
        }

        // The fall-through indicates that the artifact cannot be found;

                </mxCell>
                <mxCell id="85" value="&lt;span style=&quot;font-family: &amp;#34;roboto&amp;#34; ; font-size: 24px&quot;&gt;Plain response from: someapp.example.com&lt;/span&gt;" style="shape=hexagon;perimeter=hexagonPerimeter2;whiteSpace=wrap;html=1;fixedSize=1;strokeColor=#9673a6;strokeWidth=3;fillColor=#e1d5e7;" parent="1" vertex="1">

pkg go/doc/comment, type Parser struct, LookupSym func(string, string) bool #51082
pkg go/doc/comment, type Parser struct, Words map[string]string #51082
pkg go/doc/comment, type Plain string #51082
pkg go/doc/comment, type Printer struct #51082
pkg go/doc/comment, type Printer struct, DocLinkBaseURL string #51082
pkg go/doc/comment, type Printer struct, DocLinkURL func(*DocLink) string #51082

 *       considered "compiled comments."
 *   <li>An explicit {@code if/throw} (as illustrated below) is always acceptable; we still
 *       recommend using our {@link VerifyException} exception type. Throwing a plain {@link
 *       RuntimeException} is frowned upon.
 *   <li>Use of {@link java.util.Objects#requireNonNull(Object)} is generally discouraged, since

are hence enabled by default. This will be fixed in a future release.
[#38593](https://github.com/kubernetes/kubernetes/issues/38593)
* Federation control plane can be upgraded by updating the image
fields in the `Deployment` specs of the control plane components.
However, federation control plane upgrades were not tested in this
release [38537](https://github.com/kubernetes/kubernetes/issues/38537)

## Notable Changes to Existing Behavior

/// tip

This is how you would handle **passwords**. Receive them, but don't return them in the API.

You would also **hash** the values of the passwords before storing them, **never store them in plain text**.

///

The fields of `HeroCreate` are:

* `name`
* `age`
* `secret_name`

{* ../../docs_src/sql_databases/tutorial002_an_py310.py ln[7:22] hl[21:22] *}

    }
  }

  /**
   * Returns a {@link Collection} of all the permutations of the specified {@link Collection}.
   *
   * <p><i>Notes:</i> This is an implementation of the Plain Changes algorithm for permutations
   * generation, described in Knuth's "The Art of Computer Programming", Volume 4, Chapter 7,
   * Section 7.2.1.2.
   *

- Restores priority of static control plane pods in the cluster/gce/manifests control-plane manifests ([#89970](https://github.com/kubernetes/kubernetes/pull/89970), [@liggitt](https://github.com/liggitt)) [SIG Cluster Lifecycle and Node]


# v1.18.1