{"id":543,"date":"2020-12-18T10:26:15","date_gmt":"2020-12-18T09:26:15","guid":{"rendered":"https:\/\/mikadmin.fr\/blog\/?p=543"},"modified":"2021-04-23T21:30:33","modified_gmt":"2021-04-23T19:30:33","slug":"structure-de-ladresse-ipv4","status":"publish","type":"post","link":"https:\/\/mikadmin.fr\/blog\/structure-de-ladresse-ipv4\/","title":{"rendered":"Format de l’adresse IPv4"},"content":{"rendered":"<\/span> 2<\/span> min read<\/span><\/span>

Views: 370<\/p>\n

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Une adresse IPv4<\/span><\/strong> est compos\u00e9e de 32 bits<\/span><\/strong>, 4 octets<\/span><\/strong> de 8 bits<\/span><\/strong>.<\/p>\n\n\n\n

\"IPv4<\/figure><\/div>\n\n\n\n

Source : Wikip\u00e9dia<\/a><\/p>\n\n\n\n

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Conversion d’une adresse IP en binaire :<\/h2>\n\n\n\n
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Dans cet exemple, nous allons prendre comme exemple la fameuse adresse IPv4<\/span><\/strong> :<\/p>\n\n\n\n

192<\/span>.168<\/span>.1<\/span>.1<\/span><\/strong><\/p>\n\n\n\n

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Nous allons convertir cette derni\u00e8re en 4 \u00e9tapes<\/strong> une pour chaque octet<\/strong>.<\/p>\n\n\n\n

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Dans le syst\u00e8me binaire<\/span><\/strong>, la base est 2<\/strong>. Chaque position repr\u00e9sente une augmentation de la puissance de 2<\/strong> et ce qui donne donc pour r\u00e9f\u00e9rence :<\/p>\n\n\n\n

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128<\/td>64<\/td>32<\/td>16<\/td>8<\/td>4<\/td>2<\/td>1<\/td><\/tr>
27<\/sup><\/td>26<\/sup><\/td>25<\/sup><\/td>24<\/sup><\/td>23<\/sup><\/td>22<\/sup><\/td>21<\/sup><\/td>20<\/sup><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
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Nous nous appuyons donc sur le tableau ci-dessus :<\/p>\n\n\n\n

Premier octet<\/span><\/strong><\/p>\n\n\n\n

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192 = 128 + 64<\/strong> <\/p>\n\n\n\n

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128<\/td>64<\/td>32<\/td>16<\/td>8<\/td>4<\/td>2<\/td>1<\/td><\/tr>
1<\/td>1<\/td>0<\/td>0<\/td>0<\/td>0<\/td>0<\/td>0<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Ce qui nous donnes en notation binaire<\/strong> 11000000<\/strong><\/span> pour le premier octet<\/strong>.<\/p>\n\n\n\n

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Deuxi\u00e8me octet<\/span><\/strong><\/p>\n\n\n\n

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168 = 128 + 32 + 8<\/strong><\/p>\n\n\n\n

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128<\/td>64<\/td>32<\/td>16<\/td>8<\/td>4<\/td>2<\/td>1<\/td><\/tr>
1<\/td>0<\/td>1<\/td>0<\/td>1<\/td>0<\/td>0<\/td>0<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Ce qui nous donnes en notation binaire<\/strong> 10101000<\/span><\/strong> pour le second octet<\/a><\/strong>.<\/p>\n\n\n\n

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Troisi\u00e8me octet<\/span><\/strong><\/p>\n\n\n\n

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Nous activons simplement le dernier bit \u00e0 1<\/strong>.<\/p>\n\n\n\n

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128<\/td>64<\/td>32<\/td>16<\/td>8<\/td>4<\/td>2<\/td>1<\/td><\/tr>
0<\/td>0<\/td>0<\/td>0<\/td>0<\/td>0<\/td>0<\/td>1<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Ce qui nous donnes en notation binaire<\/strong> 00000001<\/span><\/strong> pour le troisi\u00e8me<\/strong> et le quatri\u00e8me octet de l’adresse IPv4<\/span>.<\/strong><\/p>\n\n\n\n

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R\u00e9sultat final :<\/strong><\/p>\n\n\n\n

192<\/td>168<\/td>1<\/td>1<\/td><\/tr>
11000000<\/span><\/strong><\/td>10101000<\/strong><\/span><\/td>00000001<\/span><\/strong><\/td>00000001<\/strong><\/span><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
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Conversion d’une adresse IP au format binaire en d\u00e9cimal :<\/h2>\n\n\n\n
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Il est temps \u00e0 pr\u00e9sent de faire l’inverse !<\/p>\n\n\n\n

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Notre exemple de notation binaire<\/strong> est le suivant : 01001110<\/span>.01111110<\/span>.01000010<\/span>.00000111<\/span><\/strong><\/p>\n\n\n\n

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Ici aussi nous allons d\u00e9composer la conversion en 4 \u00e9tapes<\/strong> :<\/p>\n\n\n\n

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Premier octet<\/span><\/strong><\/p>\n\n\n\n

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01001110<\/span> = 78<\/strong><\/p>\n\n\n\n

Il nous suffit donc d’entrer notre premier octet<\/strong> et d’ajouter les valeurs d\u00e9cimales. <\/strong><\/p>\n\n\n\n

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128<\/td>64<\/td>32<\/td>16<\/td>8<\/td>4<\/td>2<\/td>1<\/td><\/tr>
0<\/td>1<\/td>0<\/td>0<\/td>1<\/td>1<\/td>1<\/td>0<\/td><\/tr><\/tbody><\/table>
64 + 8 + 4 + 2<\/figcaption><\/figure>\n\n\n\n
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Deuxi\u00e8me octet<\/span> <\/strong><\/p>\n\n\n\n

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01111110<\/span> = 126<\/strong><\/p>\n\n\n\n

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128<\/td>64<\/td>32<\/td>16<\/td>8<\/td>4<\/td>2<\/td>1<\/td><\/tr>
0<\/td>1<\/td>1<\/td>1<\/td>1<\/td>1<\/td>1<\/td>0<\/td><\/tr><\/tbody><\/table>
64 + 32 + 16 +8 + 4 + 2<\/figcaption><\/figure>\n\n\n\n
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Troisi\u00e8me octet<\/span> <\/strong><\/p>\n\n\n\n

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01000010<\/span> = 66<\/strong><\/p>\n\n\n\n

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128<\/td>64<\/td>32<\/td>16<\/td>8<\/td>4<\/td>2<\/td>1<\/td><\/tr>
0<\/td>1<\/td>0<\/td>0<\/td>0<\/td>0<\/td>1<\/td>0<\/td><\/tr><\/tbody><\/table>
64 + 2<\/figcaption><\/figure>\n\n\n\n
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Quatri\u00e8me octet<\/span><\/strong><\/p>\n\n\n\n

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00000111<\/span> = 7<\/strong><\/p>\n\n\n\n

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128<\/td>64<\/td>32<\/td>16<\/td>8<\/td>4<\/td>2<\/td>1<\/td><\/tr>
0<\/td>0<\/td>0<\/td>0<\/td>0<\/td>1<\/td>1<\/td>1<\/td><\/tr><\/tbody><\/table>
4 + 2 + 1<\/figcaption><\/figure>\n\n\n\n

La notation d\u00e9cimale<\/strong> est donc 78.126.66.7<\/strong> !<\/p>\n\n\n\n

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R\u00e9sultat final :<\/strong><\/p>\n\n\n\n

78<\/td>126<\/td>66<\/td>7<\/td><\/tr>
01001110<\/span><\/strong><\/td>01111110<\/strong><\/span><\/td>01000010<\/span><\/strong><\/td>00000111<\/span><\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
<\/div>\n","protected":false},"excerpt":{"rendered":"

<\/span> 2<\/span> min read<\/span><\/span>Quel est le format d’une adresse IPv4 ? Continuer la lecture →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":628,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_themeisle_gutenberg_block_has_review":false,"footnotes":""},"categories":[2],"tags":[35,34,37,36,33,31],"class_list":["post-543","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-network","tag-base2","tag-binaire","tag-calcul","tag-decimal","tag-ipv4","tag-network"],"aioseo_notices":[],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/posts\/543","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/comments?post=543"}],"version-history":[{"count":0,"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/posts\/543\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/media\/628"}],"wp:attachment":[{"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/media?parent=543"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/categories?post=543"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mikadmin.fr\/blog\/wp-json\/wp\/v2\/tags?post=543"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}