It is not very popular or used nowadays.

OAuth2 doesn't specify how to encrypt the communication, it expects you to have your application served with HTTPS.

/// tip

In the section about **deployment** you will see how to set up HTTPS for free, using Traefik and Let's Encrypt.

///

## OpenID Connect { #openid-connect }

## Let's Encrypt

Avant Let's Encrypt, ces certificats HTTPS étaient vendus par des tiers de confiance.

Le processus d'acquisition d'un de ces certificats était auparavant lourd, nécessitait pas mal de paperasses et les certificats étaient assez chers.

Mais ensuite, <a href="https://letsencrypt.org/" class="external-link" target="_blank">Let's Encrypt</a> a été créé.

* Nginx
* HAProxy

## Let's Encrypt { #lets-encrypt }

Antes de Let's Encrypt, estos **certificados HTTPS** eran vendidos por terceros.

El proceso para adquirir uno de estos certificados solía ser complicado, requerir bastante papeleo y los certificados eran bastante costosos.

Pero luego se creó **<a href="https://letsencrypt.org/" class="external-link" target="_blank">Let's Encrypt</a>**.

     *            The string. Must not be {@literal null}.
     * @param ctype
     *            The array of character types. Must not be {@literal null} or empty.
     */
    public Tokenizer(final String str, final byte[] ctype) {
        assertArgumentNotNull("str", str);
        assertArgumentNotEmpty("ctype", ctype);

        this.str = str;
        this.ctype = ctype;
    }

    /**
     * Sets up the character type array.

//
// ## SSE-C
//
// SSE-C computes the key-encryption-key from the client-provided key, an
// initialization vector (IV) and the bucket/object path.
//
//  1. Encrypt:
//     Input: ClientKey, bucket, object, metadata, object_data
//     -              IV := Random({0,1}²⁵⁶)
//     -       ObjectKey := SHA256(ClientKey || Random({0,1}²⁵⁶))

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//DBFLUTE//DTD LastaDi 1.0//EN"
	"http://dbflute.org/meta/lastadi10.dtd">
<components>
	<component name="scoreUpdater" class="org.codelibs.fess.score.ScoreUpdater">
	</component>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//DBFLUTE//DTD LastaDi 1.0//EN"
	"http://dbflute.org/meta/lastadi10.dtd">
<components>
	<include path="convention.xml"/>
    <component name="pagerCreator" class="org.codelibs.fess.mylasta.creator.PagerCreator"/>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//DBFLUTE//DTD LastaDi 1.0//EN"
	"http://dbflute.org/meta/lastadi10.dtd">
<components>
	<include path="convention.xml" />
	<include path="lastaflute_core.xml"/>
	<include path="fess.xml" />

	<include path="crawler_opensearch.xml" />
	<include path="fess_thumbnail.xml"/>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//DBFLUTE//DTD LastaDi 1.0//EN"
	"http://dbflute.org/meta/lastadi10.dtd">
<components namespace="fessCrawler">
	<include path="crawler/container.xml" />

	<component name="contentLengthHelper"
		class="org.codelibs.fess.crawler.helper.ContentLengthHelper" instance="singleton">
	</component>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//DBFLUTE//DTD LastaDi 1.0//EN"
	"http://dbflute.org/meta/lastadi10.dtd">
<components namespace="fessCrawler">
	<include path="crawler/container.xml" />

	<component name="intervalController"
		class="org.codelibs.fess.crawler.interval.impl.DefaultIntervalController"
		instance="prototype">
	</component>