{"id":476315,"date":"2023-08-09T07:28:31","date_gmt":"2023-08-09T07:28:31","guid":{"rendered":""},"modified":"2023-09-05T11:12:27","modified_gmt":"2023-09-05T11:12:27","slug":"cold-boot","status":"publish","type":"wiki","link":"https:\/\/oneproxy.pro\/fr\/wiki\/cold-boot\/","title":{"rendered":"D\u00e9marrage \u00e0 froid"},"content":{"rendered":"<p>Le d\u00e9marrage \u00e0 froid, \u00e9galement appel\u00e9 d\u00e9marrage dur, fait r\u00e9f\u00e9rence au processus de d\u00e9marrage d&#039;un ordinateur \u00e0 partir d&#039;un \u00e9tat \u00e9teint ou \u00ab\u00a0\u00e0 froid\u00a0\u00bb. Ce terme est souvent juxtapos\u00e9 \u00e0 \u00ab\u00a0d\u00e9marrage \u00e0 chaud\u00a0\u00bb, qui signifie red\u00e9marrer un ordinateur d\u00e9j\u00e0 en cours d&#039;ex\u00e9cution.<\/p>\n<h2>L&#039;\u00e9volution et les premi\u00e8res mentions du d\u00e9marrage \u00e0 froid<\/h2>\n<p>Le terme \u00ab d\u00e9marrage \u00e0 froid \u00bb est apparu aux d\u00e9buts de l\u2019informatique, lorsqu\u2019il \u00e9tait n\u00e9cessaire de d\u00e9marrer un ordinateur alors qu\u2019il \u00e9tait compl\u00e8tement hors tension. C\u2019\u00e9tait \u00e0 l\u2019\u00e9poque des ordinateurs centraux, qui \u00e9taient les pr\u00e9d\u00e9cesseurs des machines informatiques modernes. La premi\u00e8re mention d\u2019un \u00ab d\u00e9marrage \u00e0 froid \u00bb remonte aux manuels et guides informatiques des ann\u00e9es 1950 et 1960. Le terme \u00e9tait utilis\u00e9 pour le diff\u00e9rencier du \u00ab d\u00e9marrage \u00e0 chaud \u00bb, qui consistait en un red\u00e9marrage de l&#039;ordinateur alors qu&#039;il \u00e9tait encore sous tension.<\/p>\n<h2>Aller plus loin\u00a0: d\u00e9voiler les subtilit\u00e9s du d\u00e9marrage \u00e0 froid<\/h2>\n<p>Un processus de d\u00e9marrage \u00e0 froid d\u00e9marre lors de la mise sous tension d&#039;un ordinateur enti\u00e8rement \u00e9teint. Le processus commence par l&#039;alimentation \u00e9lectrique fournissant une alimentation initiale, qui d\u00e9marre la s\u00e9quence de d\u00e9marrage. Cela lance une s\u00e9rie de v\u00e9rifications mat\u00e9rielles, connues sous le nom d&#039;autotest \u00e0 la mise sous tension (POST). Le BIOS (Basic Input Output System), qui est un micrologiciel stock\u00e9 sur une puce de la carte m\u00e8re, supervise ce processus. Il v\u00e9rifie les composants mat\u00e9riels pour s&#039;assurer que tout fonctionne correctement.<\/p>\n<p>Si le POST r\u00e9ussit, le BIOS localise ensuite le logiciel du chargeur de d\u00e9marrage sur le lecteur de stockage, le charge dans la m\u00e9moire de l&#039;ordinateur et lui donne le contr\u00f4le de l&#039;ordinateur. Le chargeur de d\u00e9marrage charge ensuite le syst\u00e8me d&#039;exploitation en m\u00e9moire, qui prend en charge et termine le processus de d\u00e9marrage.<\/p>\n<h2>D\u00e9composer le processus de d\u00e9marrage \u00e0 froid<\/h2>\n<p>La structure interne du processus de d\u00e9marrage \u00e0 froid implique une s\u00e9rie d&#039;\u00e9tapes\u00a0:<\/p>\n<ol>\n<li>Mise sous tension\u00a0: il s&#039;agit de la phase initiale au cours de laquelle le bouton d&#039;alimentation de l&#039;ordinateur est enfonc\u00e9.<\/li>\n<li>Auto-test \u00e0 la mise sous tension (POST)\u00a0: le BIOS effectue une s\u00e9rie de tests pour garantir que tous les composants mat\u00e9riels fonctionnent correctement.<\/li>\n<li>Transfert de d\u00e9marrage du BIOS\u00a0: le BIOS identifie le p\u00e9riph\u00e9rique amor\u00e7able (comme un disque dur ou un SSD) et confie le processus de d\u00e9marrage au chargeur de d\u00e9marrage stock\u00e9 sur ce p\u00e9riph\u00e9rique.<\/li>\n<li>Fonctionnement du chargeur de d\u00e9marrage\u00a0: le chargeur de d\u00e9marrage localise et charge le syst\u00e8me d&#039;exploitation dans la m\u00e9moire de l&#039;ordinateur.<\/li>\n<li>D\u00e9marrage du syst\u00e8me d&#039;exploitation\u00a0: le syst\u00e8me d&#039;exploitation prend le relais, initialisant ses syst\u00e8mes et pr\u00e9parant l&#039;interaction de l&#039;utilisateur.<\/li>\n<\/ol>\n<h2>Principales caract\u00e9ristiques du d\u00e9marrage \u00e0 froid<\/h2>\n<p>Voici les principales caract\u00e9ristiques d\u2019un d\u00e9marrage \u00e0 froid\u00a0:<\/p>\n<ul>\n<li>Il d\u00e9marre l&#039;ordinateur \u00e0 partir d&#039;un \u00e9tat compl\u00e8tement hors tension.<\/li>\n<li>Cela implique une v\u00e9rification compl\u00e8te du mat\u00e9riel lors du POST.<\/li>\n<li>Il initialise tout le mat\u00e9riel et les logiciels du syst\u00e8me \u00e0 partir de z\u00e9ro.<\/li>\n<li>Il permet d&#039;acc\u00e9der aux param\u00e8tres du BIOS.<\/li>\n<li>Il efface la m\u00e9moire volatile (RAM), \u00e9liminant ainsi tous les restes de donn\u00e9es des op\u00e9rations pr\u00e9c\u00e9dentes.<\/li>\n<\/ul>\n<h2>Diff\u00e9rencier les types de d\u00e9marrage<\/h2>\n<p>Il existe principalement deux types de processus de d\u00e9marrage\u00a0: le d\u00e9marrage \u00e0 froid et le d\u00e9marrage \u00e0 chaud.<\/p>\n<table>\n<thead>\n<tr>\n<th><\/th>\n<th>D\u00e9marrage \u00e0 froid<\/th>\n<th>D\u00e9marrage \u00e0 chaud<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u00c9tat de d\u00e9part<\/td>\n<td>\u00c9tat non aliment\u00e9<\/td>\n<td>\u00c9tat d\u00e9j\u00e0 en cours d&#039;ex\u00e9cution<\/td>\n<\/tr>\n<tr>\n<td>POSTE<\/td>\n<td>R\u00e9alis\u00e9<\/td>\n<td>Saut\u00e9<\/td>\n<\/tr>\n<tr>\n<td>R\u00e9initialisation du syst\u00e8me<\/td>\n<td>Complet<\/td>\n<td>Partiel<\/td>\n<\/tr>\n<tr>\n<td>RAM<\/td>\n<td>Effac\u00e9<\/td>\n<td>Inchang\u00e9<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Utilisations pratiques et r\u00e9solutions de probl\u00e8mes<\/h2>\n<p>Le processus de d\u00e9marrage \u00e0 froid est la m\u00e9thode standard pour d\u00e9marrer un ordinateur. Cependant, il est \u00e9galement utilis\u00e9 lorsqu&#039;un syst\u00e8me ne r\u00e9pond pas ou lorsque des modifications mat\u00e9rielles ou logicielles importantes ont \u00e9t\u00e9 apport\u00e9es, n\u00e9cessitant une initialisation compl\u00e8te du syst\u00e8me.<\/p>\n<p>En termes de probl\u00e8mes, l&#039;un des probl\u00e8mes les plus courants est celui o\u00f9 un ordinateur ne d\u00e9marre pas, ce qui peut \u00eatre d\u00fb \u00e0 des pannes mat\u00e9rielles ou logicielles. Dans ces cas, la solution implique g\u00e9n\u00e9ralement le remplacement du mat\u00e9riel ou la r\u00e9installation du logiciel.<\/p>\n<p>Un autre probl\u00e8me concerne l&#039;attaque par d\u00e9marrage \u00e0 froid, une m\u00e9thode avanc\u00e9e d&#039;extraction des cl\u00e9s de chiffrement d&#039;un ordinateur en cours d&#039;ex\u00e9cution en le red\u00e9marrant sans permettre \u00e0 la m\u00e9moire de s&#039;effacer.<\/p>\n<h2>Analyse comparative et distinctions<\/h2>\n<p>Voici une comparaison entre Cold Boot, Warm Boot et Hybrid Boot (une fonctionnalit\u00e9 de Windows 8 et versions ult\u00e9rieures)\u00a0:<\/p>\n<table>\n<thead>\n<tr>\n<th><\/th>\n<th>D\u00e9marrage \u00e0 froid<\/th>\n<th>D\u00e9marrage \u00e0 chaud<\/th>\n<th>D\u00e9marrage hybride<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u00c9tat de d\u00e9part<\/td>\n<td>\u00c9tat non aliment\u00e9<\/td>\n<td>\u00c9tat d\u00e9j\u00e0 en cours d&#039;ex\u00e9cution<\/td>\n<td>D\u00e9marrage rapide avec hibernation partielle<\/td>\n<\/tr>\n<tr>\n<td>POSTE<\/td>\n<td>R\u00e9alis\u00e9<\/td>\n<td>Saut\u00e9<\/td>\n<td>Saut\u00e9<\/td>\n<\/tr>\n<tr>\n<td>R\u00e9initialisation du syst\u00e8me<\/td>\n<td>Complet<\/td>\n<td>Partiel<\/td>\n<td>Partiel<\/td>\n<\/tr>\n<tr>\n<td>RAM<\/td>\n<td>Effac\u00e9<\/td>\n<td>Inchang\u00e9<\/td>\n<td>Inchang\u00e9<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>L&#039;avenir des processus de d\u00e9marrage<\/h2>\n<p>L\u2019avenir des processus de d\u00e9marrage implique probablement des temps de d\u00e9marrage plus rapides et des syst\u00e8mes plus s\u00e9curis\u00e9s. Des technologies telles que les SSD et l&#039;UEFI (Unified Extensible Firmware Interface) contribuent \u00e0 ces avanc\u00e9es, r\u00e9duisant consid\u00e9rablement les temps de d\u00e9marrage. Des mesures de s\u00e9curit\u00e9, telles que le d\u00e9marrage s\u00e9curis\u00e9 et le TPM (Trusted Platform Module), sont mises en \u0153uvre pour emp\u00eacher tout acc\u00e8s non autoris\u00e9 au syst\u00e8me.<\/p>\n<h2>D\u00e9marrage \u00e0 froid et serveurs proxy<\/h2>\n<p>Les serveurs proxy ne sont pas directement li\u00e9s au processus de d\u00e9marrage \u00e0 froid car ils font partie de l&#039;infrastructure r\u00e9seau. Cependant, lorsqu&#039;un ordinateur subit un d\u00e9marrage \u00e0 froid, les param\u00e8tres r\u00e9seau (y compris ceux d&#039;un serveur proxy s&#039;il est utilis\u00e9) sont initialis\u00e9s et charg\u00e9s pendant le processus de d\u00e9marrage. Si un syst\u00e8me s&#039;appuie sur un proxy pour l&#039;acc\u00e8s au r\u00e9seau, toute modification importante de la configuration r\u00e9seau du syst\u00e8me peut n\u00e9cessiter un d\u00e9marrage \u00e0 froid.<\/p>\n<h2>Liens connexes<\/h2>\n<p>Pour plus d&#039;informations sur le d\u00e9marrage \u00e0 froid, vous pouvez consulter ces ressources\u00a0:<\/p>\n<ul>\n<li><a href=\"https:\/\/www.computerhope.com\/jargon\/c\/coldboot.htm\" target=\"_new\" rel=\"noopener nofollow\">Espoir informatique\u00a0: d\u00e9marrage \u00e0 froid<\/a><\/li>\n<li><a href=\"https:\/\/www.techopedia.com\/definition\/3851\/cold-booting\" target=\"_new\" rel=\"noopener nofollow\">Techopedia\u00a0: D\u00e9marrage \u00e0 froid<\/a><\/li>\n<li><a href=\"https:\/\/en.wikipedia.org\/wiki\/Booting\" target=\"_new\" rel=\"noopener nofollow\">Wikip\u00e9dia\u00a0:\u00a0d\u00e9marrage<\/a><\/li>\n<\/ul>","protected":false},"featured_media":467902,"menu_order":0,"template":"","meta":{"_acf_changed":false,"content-type":"","inline_featured_image":false,"footnotes":""},"class_list":["post-476315","wiki","type-wiki","status-publish","has-post-thumbnail","hentry"],"acf":{"faq_title":"Frequently Asked Questions about <mark>An Extensive Examination of Cold Boot<\/mark>","faq_items":[{"question":"What is a cold boot?","answer":"<p>A cold boot, also known as a hard boot, refers to the process of starting a computer from a powered-off, or \"cold,\" state. It involves a series of checks and initializations performed by the computer's BIOS and boot loader.<\/p>"},{"question":"What is the origin of the term cold boot?","answer":"<p>The term \"cold boot\" originated during the early days of computing, when mainframe computers were prevalent. The term was used to differentiate it from the \"warm boot,\" which was a restart of the computer while it was still powered.<\/p>"},{"question":"What is the process involved in a cold boot?","answer":"<p>A cold boot process involves the initial power-on, a series of hardware checks conducted by the BIOS known as the Power-On Self Test (POST), locating and loading the boot loader software by the BIOS, and finally, the loading and initializing of the operating system.<\/p>"},{"question":"What are the key features of a cold boot?","answer":"<p>The key features of a cold boot include starting the computer from a completely unpowered state, a comprehensive hardware check during the POST, initializing all system hardware and software from scratch, accessing BIOS settings, and clearing out the volatile memory (RAM).<\/p>"},{"question":"How does a cold boot compare to a warm boot?","answer":"<p>A cold boot starts the computer from a completely unpowered state and involves a comprehensive system reset, while a warm boot restarts a computer that's already running and only involves a partial system reset.<\/p>"},{"question":"What problems might arise during a cold boot and how can they be solved?","answer":"<p>Common problems during a cold boot can include a computer failing to start due to hardware or software failures, which usually require hardware replacement or software reinstallation. Another issue is a cold boot attack, where encryption keys are extracted from a running computer by rebooting it without allowing the memory to clear.<\/p>"},{"question":"How does the future look for booting processes?","answer":"<p>The future of booting processes involves faster boot times and more secure systems. This is thanks to technologies like SSDs and UEFI, which significantly reduce boot times, and security measures like secure boot and TPM to prevent unauthorized system access.<\/p>"},{"question":"How is a cold boot related to proxy servers?","answer":"<p>While proxy servers aren't directly related to the cold boot process, network settings (including those of a proxy server) are initialized and loaded during the boot process. If a system relies on a proxy for network access, any significant changes in the system's network configuration may necessitate a cold boot.<\/p>"}]},"_links":{"self":[{"href":"https:\/\/oneproxy.pro\/fr\/wp-json\/wp\/v2\/wiki\/476315","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/oneproxy.pro\/fr\/wp-json\/wp\/v2\/wiki"}],"about":[{"href":"https:\/\/oneproxy.pro\/fr\/wp-json\/wp\/v2\/types\/wiki"}],"version-history":[{"count":0,"href":"https:\/\/oneproxy.pro\/fr\/wp-json\/wp\/v2\/wiki\/476315\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/oneproxy.pro\/fr\/wp-json\/wp\/v2\/media\/467902"}],"wp:attachment":[{"href":"https:\/\/oneproxy.pro\/fr\/wp-json\/wp\/v2\/media?parent=476315"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}