{"id":126,"date":"2025-11-13T09:37:38","date_gmt":"2025-11-13T08:37:38","guid":{"rendered":"https:\/\/yb-isn.fr\/2025\/nsi\/?p=126"},"modified":"2025-11-20T09:23:22","modified_gmt":"2025-11-20T08:23:22","slug":"internet-et-reseau-rappels","status":"publish","type":"post","link":"https:\/\/yb-isn.fr\/2025\/nsi\/2025\/11\/13\/internet-et-reseau-rappels\/","title":{"rendered":"16- Internet et r\u00e9seau : rappels"},"content":{"rendered":"<p><!--more--><\/p>\n\n\n<div class=\"wp-block-esab-accordion esab-2fw0s3na\" data-mode=\"global\"><div class=\"esab__container\">\n<div class=\"wp-block-esab-accordion-child\"><div class=\"esab__head\" role=\"button\" aria-expanded=\"false\"><div class=\"esab__heading_txt\"><p class=\"esab__heading_tag\">Questionnaire<\/p><\/div><div class=\"esab__icon\"><div class=\"esab__collapse\"> <svg version=\"1.2\" viewBox=\"0 0 24 24\" width=\"24\" height=\"24\"><path fill-rule=\"evenodd\" d=\"m3.5 20.5c-4.7-4.7-4.7-12.3 0-17 4.7-4.7 12.3-4.7 17 0 4.6 4.7 4.6 12.3 0 17-4.7 4.6-12.3 4.6-17 0zm0.9-0.9c4.2 4.2 11 4.2 15.2 0 4.2-4.2 4.2-11 0-15.2-4.2-4.3-11-4.3-15.2 0-4.3 4.2-4.3 11 0 15.2z\"><\/path><path d=\"m11.4 15.9v-3.3h-3.3c-0.3 0-0.6-0.3-0.6-0.6 0-0.4 0.3-0.6 0.6-0.6h3.3v-3.3c0-0.3 0.3-0.6 0.6-0.6 0.3 0 0.6 0.3 0.6 0.6v3.3h3.3c0.3 0 0.6 0.2 0.6 0.6q0 0.2-0.2 0.4-0.2 0.2-0.4 0.2h-3.3v3.3q0 0.2-0.2 0.4-0.2 0.2-0.4 0.2c-0.4 0-0.6-0.3-0.6-0.6z\"><\/path><\/svg> <\/div><div class=\"esab__expand\"> <svg version=\"1.2\" viewBox=\"0 0 24 24\" width=\"24\" height=\"24\"><path fill-rule=\"evenodd\" d=\"m12 24c-6.6 0-12-5.4-12-12 0-6.6 5.4-12 12-12 6.6 0 12 5.4 12 12 0 6.6-5.4 12-12 12zm10.6-12c0-5.9-4.7-10.6-10.6-10.6-5.9 0-10.6 4.7-10.6 10.6 0 5.9 4.7 10.6 10.6 10.6 5.9 0 10.6-4.7 10.6-10.6z\"><\/path><path d=\"m5.6 11.3h12.8v1.4h-12.8z\"><\/path><\/svg> <\/div><\/div><\/div><div class=\"esab__body\">\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"778\" src=\"https:\/\/yb-isn.fr\/2025\/nsi\/wp-content\/uploads\/2025\/11\/image-2-1024x778.png\" alt=\"\" class=\"wp-image-159\" srcset=\"https:\/\/yb-isn.fr\/2025\/nsi\/wp-content\/uploads\/2025\/11\/image-2-1024x778.png 1024w, https:\/\/yb-isn.fr\/2025\/nsi\/wp-content\/uploads\/2025\/11\/image-2-300x228.png 300w, https:\/\/yb-isn.fr\/2025\/nsi\/wp-content\/uploads\/2025\/11\/image-2-768x583.png 768w, https:\/\/yb-isn.fr\/2025\/nsi\/wp-content\/uploads\/2025\/11\/image-2.png 1132w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n<\/div><\/div>\n<\/div><\/div>\n\n\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-background has-link-color wp-elements-1\" style=\"background:linear-gradient(135deg,rgb(216,244,179) 0%,rgb(17,184,81) 100%)\">1)&nbsp; D\u00e9finitions -historique<\/h2>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Le web ou world wide web est une application d\u2019internet parmi tant d\u2019autres. On parle de toile d\u2019araign\u00e9e mondiale. <\/p>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Il ne faut donc pas confondre web et internet.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-1.png\" alt=\"\" class=\"wp-image-72\"\/><\/figure>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Internet est un r\u00e9seau physique&nbsp;: r\u00e9seau de r\u00e9seaux C\u2019est un ensemble d\u2019\u00e9quipements (routeurs ,c\u00e2bles , fibres optiques ordinateurs switches\u2026) reli\u00e9s entre eux pour \u00e9changer des informations.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image.png\" alt=\"\" class=\"wp-image-70\"\/><\/figure>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">L\u2019information se pr\u00e9sente sous forme de bits.&nbsp;&nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-14.png\" alt=\"\" class=\"wp-image-131\"\/><\/figure>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Le bit est l\u2019unit\u00e9 d\u2019information \u00e9l\u00e9mentaire manipulable par un ordinateur, ayant la valeur 1 ou 0.<\/p>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">On parle alors de donn\u00e9es num\u00e9riques.<\/p>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Pour transmettre des donn\u00e9es il faut un canal (une ligne de transmission)entre des machines.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Quelques d\u00e9bits:<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"945\" height=\"520\" src=\"https:\/\/yb-isn.fr\/2025\/nsi\/wp-content\/uploads\/2025\/11\/image-1.png\" alt=\"\" class=\"wp-image-154\" srcset=\"https:\/\/yb-isn.fr\/2025\/nsi\/wp-content\/uploads\/2025\/11\/image-1.png 945w, https:\/\/yb-isn.fr\/2025\/nsi\/wp-content\/uploads\/2025\/11\/image-1-300x165.png 300w, https:\/\/yb-isn.fr\/2025\/nsi\/wp-content\/uploads\/2025\/11\/image-1-768x423.png 768w\" sizes=\"auto, (max-width: 945px) 100vw, 945px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Vous pouvez mesurer le d\u00e9bit de votre connexion et la latence :<a href=\"https:\/\/www.journaldunet.fr\/web-tech\/dictionnaire-du-webmastering\/1487601-test-debit-internet\/\">Mesure du d\u00e9bit<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">d\u00e9bits actuels : le 10\/12\/2024<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ci-dessous des mesures effectu\u00e9es sur mes \u00e9quipements.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-29.png\" alt=\"\" class=\"wp-image-233\"\/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Deux grandeurs importantes  le d\u00e9bit et la latence.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">La latence est le temps que met le message \u00e0 arriver. \u00ab\u00a0Vous ouvrez le robinet et vous mesurez le temps pour que l&rsquo;eau commence \u00e0 couler.\u00a0\u00bb<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Le d\u00e9bit est le nombre de bit par seconde. \u00ab\u00a0L&rsquo;eau commence \u00e0 couler et vous mesurez le nombre de litres qui s&rsquo;\u00e9coulent en 1 seconde\u00a0\u00bb<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Quelques rep\u00e8res historiques<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-30.png\" alt=\"\" class=\"wp-image-239\"\/><\/figure>\n\n\n\n<figure class=\"wp-block-embed is-type-wp-embed is-provider-sciences-num-riques-et-technologie wp-block-embed-sciences-num-riques-et-technologie\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"wp-embedded-content\" data-secret=\"XuVLLsUSpg\"><a href=\"https:\/\/yb-isn.fr\/snt\/?p=195\">Du t\u00e9l\u00e9graphe au t\u00e9l\u00e9phone filaire<\/a><\/blockquote><iframe loading=\"lazy\" class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; visibility: hidden;\" title=\"\u00ab\u00a0Du t\u00e9l\u00e9graphe au t\u00e9l\u00e9phone filaire\u00a0\u00bb &#8212; Sciences Num\u00e9riques et technologie\" src=\"https:\/\/yb-isn.fr\/snt\/?p=195&#038;embed=true#?secret=NqrpGWblHn#?secret=XuVLLsUSpg\" data-secret=\"XuVLLsUSpg\" width=\"600\" height=\"338\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe>\n<\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/yb-isn.fr\/snt\/?p=151\" data-type=\"link\" data-id=\"https:\/\/yb-isn.fr\/snt\/?p=151\">c\u00e2bles sous marins<\/a><\/p>\n\n\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-background has-link-color wp-elements-2\" style=\"background:linear-gradient(135deg,rgb(216,244,179) 0%,rgb(17,184,81) 100%)\">2)&nbsp; Adressage IP<\/h2>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Les adresses IP sont les num\u00e9ros qui permettent aux ordinateurs et aux objets connect\u00e9s de communiquer les uns avec les autres sur internet.<\/p>\n\n\n\n<marquee><b>Exercice \u00e0 traiter<\/b><\/marquee>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button\"><a class=\"wp-block-button__link wp-element-button\" href=\"https:\/\/capytale2.ac-paris.fr\/web\/c\/069a-4921774\">Exercice sur capytale<\/a><\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">regarder les 4 premi\u00e8res minutes.<\/p>\n\n\n\n<iframe loading=\"lazy\" src=\"https:\/\/www.youtube.com\/embed\/5o8CwafCxnU?start=0\" title=\"YouTube video player\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\" width=\"560\" height=\"315\" frameborder=\"0\"><\/iframe>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-2.png\" alt=\"\" class=\"wp-image-76\"\/><\/figure>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Certains  blocs d&rsquo;adresses priv\u00e9es commencent par 10, 172 ou 192.Les autres sont publiques.<\/p>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">La croissance du nombre d&rsquo;utilisateurs et de serveurs sur Internet s&rsquo;accompagne d&rsquo;un \u00e9puisement des adresses IPv4.<\/p>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">IPV4 permettait de distinguer (2<sup>32<\/sup>) 4 milliards d\u2019adresses<\/p>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">IPV6 permet de distinguer (2<sup>128<\/sup>)100 milliards de milliard de milliard de milliard d\u2019adresses.<\/p>\n\n\n\n<p class=\"has-cyan-bluish-gray-color has-text-color wp-block-paragraph\">Si chaque IP \u00e9tait un grains de sable de sable on aurait une masse tr\u00e8s sup\u00e9rieur \u00e0 celle de la terre!<\/p>\n\n\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-background has-link-color wp-elements-3\" style=\"background:linear-gradient(135deg,rgb(216,244,179) 0%,rgb(17,184,81) 100%)\">3)&nbsp; Adresse symbolique<\/h2>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Le syst\u00e8me DNS (Domain Name System) transforme une adresse symbolique plus facile \u00e0 retenir en adresse IP num\u00e9rique.<\/p>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Il est r\u00e9alis\u00e9 par un grand nombre d\u2019ordinateurs r\u00e9partis (de fa\u00e7on hi\u00e9rarchis\u00e9e)  dans le monde et constamment mis \u00e0 jour.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/www.youtube.com\/watch?v=5o8CwafCxnU&amp;t=249s\">https:\/\/www.youtube.com\/watch?v=5o8CwafCxnU&amp;t=249s<\/a><\/p>\n\n\n\n<iframe loading=\"lazy\" src=\"https:\/\/www.youtube.com\/embed\/5o8CwafCxnU?start=249\" title=\"YouTube video player\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\" width=\"560\" height=\"315\" frameborder=\"0\"><\/iframe>\n\n\n<div class=\"wp-block-image is-resized\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-3.png\" alt=\"\" class=\"wp-image-91\"\/><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">Le cache DNS est le stockage de l\u2019IP sur une machine ou un serveur pour acc\u00e9l\u00e9rer l\u2019acc\u00e8s \u00e0 site d\u00e9j\u00e0 visit\u00e9.<\/p>\n\n\n<div class=\"wp-block-image is-resized\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-4.png\" alt=\"\" class=\"wp-image-92\"\/><\/figure>\n<\/div>\n\n\n<h2 class=\"wp-block-heading has-black-color has-text-color has-background has-link-color wp-elements-4\" style=\"background:linear-gradient(135deg,rgb(216,244,179) 0%,rgb(17,184,81) 100%)\">4)&nbsp; Protocole TCP\/IP et routage<\/h2>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Le routage est le m\u00e9canisme par lequel des chemins sont s\u00e9lectionn\u00e9s dans un r\u00e9seau pour acheminer les donn\u00e9es d\u2019un exp\u00e9diteur jusqu\u2019\u00e0 un ou plusieurs destinataires. Les r\u00e9seaux informatiques ont mis beaucoup de temps \u00e0 d\u00e9ployer le routage dans toute sa dimension en raison des monopoles dans les t\u00e9l\u00e9communications.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-background has-link-color wp-elements-5\" style=\"background:linear-gradient(135deg,rgb(216,244,179) 0%,rgb(17,184,81) 100%)\">4.1)&nbsp; Protocole IP<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">L\u2019adresse de l\u2019\u00e9metteur et du destinataire sont transmises avec chacune des portions du message d\u00e9coup\u00e9 en paquets.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-5.png\" alt=\"\" class=\"wp-image-107\"\/><\/figure>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Le protocole IP  est insuffisant<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Il ne v\u00e9rifie pas les donn\u00e9es<\/li>\n\n\n\n<li>Ne num\u00e9rote pas les paquets<\/li>\n\n\n\n<li>Ne fait rien en cas de perte de donn\u00e9es<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-background has-link-color wp-elements-6\" style=\"background:linear-gradient(135deg,rgb(216,244,179) 0%,rgb(17,184,81) 100%)\">4.2)&nbsp; Protocole TCP<\/h3>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">Le protocole TCP assure le transport des paquets<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Num\u00e9rotant les paquets<\/li>\n\n\n\n<li>Classant les paquets<\/li>\n\n\n\n<li>Assurant l\u2019\u00e9mission d\u2019accus\u00e9s de r\u00e9ception<\/li>\n\n\n\n<li>Le renvoi de paquets si n\u00e9cessaire donc pas de perte de paquets<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-6.png\" alt=\"\" class=\"wp-image-114\"\/><\/figure>\n\n\n\n<h3 class=\"wp-block-heading has-black-color has-text-color has-background has-link-color wp-elements-7\" style=\"background:linear-gradient(135deg,rgb(216,244,179) 0%,rgb(17,184,81) 100%)\">4.3)&nbsp; Le routage des paquets<\/h3>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"http:\/\/yb-isn.fr\/snt\/wp-content\/uploads\/2022\/01\/image-7.png\" alt=\"\" class=\"wp-image-115\"\/><\/figure>\n\n\n\n<p class=\"has-vivid-red-color has-text-color wp-block-paragraph\">La communication entre deux r\u00e9seaux peut s\u2019\u00e9tablir \u00e0 travers un routeur.<br>Pour d\u00e9terminer le chemin que doit emprunter un paquet pour arriver \u00e0 destination, le routeur s\u2019appuie sur une table de routage.<br>Dans des petits r\u00e9seaux, cette table est statique et mise \u00e0 jour manuellement. Dans les r\u00e9seaux plus grands ces tables sont mises \u00e0 jour de fa\u00e7on dynamique \u00e0 l\u2019aide de protocoles sp\u00e9cifiques.<br>La table de routage n\u2019a pas besoin de d\u00e9finir tous les chemins du r\u00e9seau.<\/p>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_crdt_document":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-126","post","type-post","status-publish","format-standard","hentry","category-non-classe"],"_links":{"self":[{"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/posts\/126","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/comments?post=126"}],"version-history":[{"count":15,"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/posts\/126\/revisions"}],"predecessor-version":[{"id":164,"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/posts\/126\/revisions\/164"}],"wp:attachment":[{"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/media?parent=126"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/categories?post=126"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/yb-isn.fr\/2025\/nsi\/wp-json\/wp\/v2\/tags?post=126"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}