CINXE.COM

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>Data link layer - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available";var cookie=document.cookie.match(/(?:^|; )enwikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"1388311d-f459-4b07-97ea-ba1724e17e59","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Data_link_layer","wgTitle":"Data link layer","wgCurRevisionId":1243885558,"wgRevisionId":1243885558,"wgArticleId":152949,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["Use American English from March 2019","All Wikipedia articles written in American English","Articles with short description","Short description matches Wikidata","Use mdy dates from March 2019","CS1 maint: location","Commons category link from Wikidata","OSI model","Link protocols"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Data_link_layer","wgRelevantArticleId":152949,"wgIsProbablyEditable":true, "wgRelevantPageIsProbablyEditable":true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgFlaggedRevsParams":{"tags":{"status":{"levels":1}}},"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":false,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":20000,"wgRelatedArticlesCompat":[],"wgCentralAuthMobileDomain":false,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q194134","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"],"GEHomepageSuggestedEditsEnableTopics": true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.makeCollapsible.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["ext.cite.ux-enhancements","site","mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips","ext.gadget.switcher","ext.urlShortener.toolbar","ext.centralauth.centralautologin","mmv.bootstrap","ext.popups", "ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints","ext.growthExperiments.SuggestedEditSession","wikibase.sidebar.tracking"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&modules=ext.cite.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.makeCollapsible.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.4"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Data link layer - Wikipedia"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//en.m.wikipedia.org/wiki/Data_link_layer"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=Data_link_layer&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//en.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://en.wikipedia.org/wiki/Data_link_layer"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="//login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Data_link_layer rootpage-Data_link_layer skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navigation </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-contents" class="mw-list-item"><a href="/wiki/Wikipedia:Contents" title="Guides to browsing Wikipedia"><span>Contents</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:Current_events" title="Articles related to current events"><span>Current events</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Visit a randomly selected article [x]" accesskey="x"><span>Random article</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About" title="Learn about Wikipedia and how it works"><span>About Wikipedia</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us" title="How to contact Wikipedia"><span>Contact us</span></a></li> </ul> </div> </div> <div id="p-interaction" class="vector-menu mw-portlet mw-portlet-interaction" > <div class="vector-menu-heading"> Contribute </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="Guidance on how to use and edit Wikipedia"><span>Help</span></a></li><li id="n-introduction" class="mw-list-item"><a href="/wiki/Help:Introduction" title="Learn how to edit Wikipedia"><span>Learn to edit</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Community_portal" title="The hub for editors"><span>Community portal</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="A list of recent changes to Wikipedia [r]" accesskey="r"><span>Recent changes</span></a></li><li id="n-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_upload_wizard" title="Add images or other media for use on Wikipedia"><span>Upload file</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-en.svg" width="117" height="13" style="width: 7.3125em; height: 0.8125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page's font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&returnto=Data+link+layer" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&returnto=Data+link+layer" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Log in and more options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en"><span>Donate</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&returnto=Data+link+layer" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&returnto=Data+link+layer" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Function" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Function"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Function</span> </div> </a> <ul id="toc-Function-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Sublayers" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Sublayers"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Sublayers</span> </div> </a> <button aria-controls="toc-Sublayers-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Sublayers subsection</span> </button> <ul id="toc-Sublayers-sublist" class="vector-toc-list"> <li id="toc-Logical_link_control_sublayer" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Logical_link_control_sublayer"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Logical link control sublayer</span> </div> </a> <ul id="toc-Logical_link_control_sublayer-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Media_access_control_sublayer" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Media_access_control_sublayer"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Media access control sublayer</span> </div> </a> <ul id="toc-Media_access_control_sublayer-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Services" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Services"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Services</span> </div> </a> <ul id="toc-Services-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Error_detection_and_correction" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Error_detection_and_correction"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Error detection and correction</span> </div> </a> <ul id="toc-Error_detection_and_correction-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Protocol_examples" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Protocol_examples"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Protocol examples</span> </div> </a> <ul id="toc-Protocol_examples-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Relation_to_the_TCP/IP_model" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Relation_to_the_TCP/IP_model"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Relation to the TCP/IP model</span> </div> </a> <ul id="toc-Relation_to_the_TCP/IP_model-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Data link layer</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 44 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-44" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">44 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%B7%D8%A8%D9%82%D8%A9_%D8%B1%D8%A8%D8%B7_%D8%A7%D9%84%D8%A8%D9%8A%D8%A7%D9%86%D8%A7%D8%AA" title="طبقة ربط البيانات – Arabic" lang="ar" hreflang="ar" data-title="طبقة ربط البيانات" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Kanal_s%C9%99viyy%C9%99si" title="Kanal səviyyəsi – Azerbaijani" lang="az" hreflang="az" data-title="Kanal səviyyəsi" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%9A%D0%B0%D0%BD%D0%B0%D0%BB%D1%8C%D0%BD%D1%8B_%D1%9E%D0%B7%D1%80%D0%BE%D0%B2%D0%B5%D0%BD%D1%8C" title="Канальны ўзровень – Belarusian" lang="be" hreflang="be" data-title="Канальны ўзровень" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9A%D0%B0%D0%BD%D0%B0%D0%BB%D0%B5%D0%BD_%D1%81%D0%BB%D0%BE%D0%B9_%D0%BD%D0%B0_OSI_%D0%BC%D0%BE%D0%B4%D0%B5%D0%BB%D0%B0" title="Канален слой на OSI модела – Bulgarian" lang="bg" hreflang="bg" data-title="Канален слой на OSI модела" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Capa_d%27enlla%C3%A7_de_dades" title="Capa d'enllaç de dades – Catalan" lang="ca" hreflang="ca" data-title="Capa d'enllaç de dades" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Linkov%C3%A1_vrstva" title="Linková vrstva – Czech" lang="cs" hreflang="cs" data-title="Linková vrstva" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Datalinklaget" title="Datalinklaget – Danish" lang="da" hreflang="da" data-title="Datalinklaget" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/OSI-Modell#Schicht_2_–_Sicherungsschicht" title="OSI-Modell – German" lang="de" hreflang="de" data-title="OSI-Modell" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Kanalikiht" title="Kanalikiht – Estonian" lang="et" hreflang="et" data-title="Kanalikiht" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%95%CF%80%CE%AF%CF%80%CE%B5%CE%B4%CE%BF_%CE%B6%CE%B5%CF%8D%CE%BE%CE%B7%CF%82_%CE%B4%CE%B5%CE%B4%CE%BF%CE%BC%CE%AD%CE%BD%CF%89%CE%BD" title="Επίπεδο ζεύξης δεδομένων – Greek" lang="el" hreflang="el" data-title="Επίπεδο ζεύξης δεδομένων" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Capa_de_enlace_de_datos" title="Capa de enlace de datos – Spanish" lang="es" hreflang="es" data-title="Capa de enlace de datos" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Lotura_geruza" title="Lotura geruza – Basque" lang="eu" hreflang="eu" data-title="Lotura geruza" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%84%D8%A7%DB%8C%D9%87_%D9%BE%DB%8C%D9%88%D9%86%D8%AF_%D8%AF%D8%A7%D8%AF%D9%87%E2%80%8C%D8%A7%DB%8C" title="لایه پیوند داده‌ای – Persian" lang="fa" hreflang="fa" data-title="لایه پیوند داده‌ای" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Couche_liaison_de_donn%C3%A9es" title="Couche liaison de données – French" lang="fr" hreflang="fr" data-title="Couche liaison de données" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%8D%B0%EC%9D%B4%ED%84%B0_%EB%A7%81%ED%81%AC_%EA%B3%84%EC%B8%B5" title="데이터 링크 계층 – Korean" lang="ko" hreflang="ko" data-title="데이터 링크 계층" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Lapisan_taut_data" title="Lapisan taut data – Indonesian" lang="id" hreflang="id" data-title="Lapisan taut data" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Livello_di_collegamento_dati" title="Livello di collegamento dati – Italian" lang="it" hreflang="it" data-title="Livello di collegamento dati" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%A9%D7%9B%D7%91%D7%AA_%D7%94%D7%A7%D7%95_%D7%A9%D7%9C_%D7%9E%D7%95%D7%93%D7%9C_%D7%94-OSI" title="שכבת הקו של מודל ה-OSI – Hebrew" lang="he" hreflang="he" data-title="שכבת הקו של מודל ה-OSI" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%90%D1%80%D0%BD%D0%B0%D0%BB%D1%8B%D2%9B_%D0%B4%D0%B5%D2%A3%D0%B3%D0%B5%D0%B9" title="Арналық деңгей – Kazakh" lang="kk" hreflang="kk" data-title="Арналық деңгей" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Stratum_conexionis_datorum" title="Stratum conexionis datorum – Latin" lang="la" hreflang="la" data-title="Stratum conexionis datorum" data-language-autonym="Latina" data-language-local-name="Latin" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Datu_posma_sl%C4%81nis" title="Datu posma slānis – Latvian" lang="lv" hreflang="lv" data-title="Datu posma slānis" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lmo mw-list-item"><a href="https://lmo.wikipedia.org/wiki/Nivell_de_conligament_di_dacc" title="Nivell de conligament di dacc – Lombard" lang="lmo" hreflang="lmo" data-title="Nivell de conligament di dacc" data-language-autonym="Lombard" data-language-local-name="Lombard" class="interlanguage-link-target"><span>Lombard</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Adatkapcsolati_r%C3%A9teg" title="Adatkapcsolati réteg – Hungarian" lang="hu" hreflang="hu" data-title="Adatkapcsolati réteg" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%9F%D0%BE%D0%B4%D0%B0%D1%82%D0%BE%D1%87%D0%BD%D0%BE_%D0%BD%D0%B8%D0%B2%D0%BE" title="Податочно ниво – Macedonian" lang="mk" hreflang="mk" data-title="Податочно ниво" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Lapisan_pautan_data" title="Lapisan pautan data – Malay" lang="ms" hreflang="ms" data-title="Lapisan pautan data" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/Data_link_layer" title="Data link layer – Mongolian" lang="mn" hreflang="mn" data-title="Data link layer" data-language-autonym="Монгол" data-language-local-name="Mongolian" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Datalinklaag" title="Datalinklaag – Dutch" lang="nl" hreflang="nl" data-title="Datalinklaag" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%83%87%E3%83%BC%E3%82%BF%E3%83%AA%E3%83%B3%E3%82%AF%E5%B1%A4" title="データリンク層 – Japanese" lang="ja" hreflang="ja" data-title="データリンク層" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Datalink-laget" title="Datalink-laget – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Datalink-laget" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Datalinklaget" title="Datalinklaget – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Datalinklaget" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Warstwa_%C5%82%C4%85cza_danych" title="Warstwa łącza danych – Polish" lang="pl" hreflang="pl" data-title="Warstwa łącza danych" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Camada_de_enlace_de_dados" title="Camada de enlace de dados – Portuguese" lang="pt" hreflang="pt" data-title="Camada de enlace de dados" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9A%D0%B0%D0%BD%D0%B0%D0%BB%D1%8C%D0%BD%D1%8B%D0%B9_%D1%83%D1%80%D0%BE%D0%B2%D0%B5%D0%BD%D1%8C" title="Канальный уровень – Russian" lang="ru" hreflang="ru" data-title="Канальный уровень" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Data_Link_Layer" title="Data Link Layer – Albanian" lang="sq" hreflang="sq" data-title="Data Link Layer" data-language-autonym="Shqip" data-language-local-name="Albanian" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Vrstva_d%C3%A1tov%C3%A9ho_spoja" title="Vrstva dátového spoja – Slovak" lang="sk" hreflang="sk" data-title="Vrstva dátového spoja" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Plast_podatkovne_povezave" title="Plast podatkovne povezave – Slovenian" lang="sl" hreflang="sl" data-title="Plast podatkovne povezave" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%A1%D0%BB%D0%BE%D1%98_%D0%B2%D0%B5%D0%B7%D0%B5" title="Слој везе – Serbian" lang="sr" hreflang="sr" data-title="Слој везе" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Sloj_veze" title="Sloj veze – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Sloj veze" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Datal%C3%A4nkskikt" title="Datalänkskikt – Swedish" lang="sv" hreflang="sv" data-title="Datalänkskikt" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Veri_ba%C4%9Flant%C4%B1s%C4%B1_katman%C4%B1" title="Veri bağlantısı katmanı – Turkish" lang="tr" hreflang="tr" data-title="Veri bağlantısı katmanı" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9A%D0%B0%D0%BD%D0%B0%D0%BB%D1%8C%D0%BD%D0%B8%D0%B9_%D1%80%D1%96%D0%B2%D0%B5%D0%BD%D1%8C" title="Канальний рівень – Ukrainian" lang="uk" hreflang="uk" data-title="Канальний рівень" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/T%E1%BA%A7ng_li%C3%AAn_k%E1%BA%BFt_d%E1%BB%AF_li%E1%BB%87u" title="Tầng liên kết dữ liệu – Vietnamese" lang="vi" hreflang="vi" data-title="Tầng liên kết dữ liệu" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E6%95%B0%E6%8D%AE%E9%93%BE%E8%B7%AF%E5%B1%82" title="数据链路层 – Wu" lang="wuu" hreflang="wuu" data-title="数据链路层" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E6%95%B0%E6%8D%AE%E9%93%BE%E8%B7%AF%E5%B1%82" title="数据链路层 – Chinese" lang="zh" hreflang="zh" data-title="数据链路层" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q194134#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Data_link_layer" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Data_link_layer" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Data_link_layer"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Data_link_layer&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Data_link_layer&action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Data_link_layer"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Data_link_layer&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Data_link_layer&action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/Data_link_layer" title="List of all English Wikipedia pages containing links to this page [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/Data_link_layer" rel="nofollow" title="Recent changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_Upload_Wizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages" title="A list of all special pages [q]" accesskey="q"><span>Special pages</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Data_link_layer&oldid=1243885558" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Data_link_layer&action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&page=Data_link_layer&id=1243885558&wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FData_link_layer"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FData_link_layer"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&page=Data_link_layer&action=show-download-screen" title="Download this page as a PDF file"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Data_link_layer&printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Printable version</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="wb-otherproject-link wb-otherproject-commons mw-list-item"><a href="https://commons.wikimedia.org/wiki/Category:Data_link_layer" hreflang="en"><span>Wikimedia Commons</span></a></li><li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q194134" title="Structured data on this page hosted by Wikidata [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><p class="mw-empty-elt"> </p> <div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Second layer of the OSI networking model</div> <p class="mw-empty-elt"> </p> <style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r1246091330">.mw-parser-output .sidebar{width:22em;float:right;clear:right;margin:0.5em 0 1em 1em;background:var(--background-color-neutral-subtle,#f8f9fa);border:1px solid var(--border-color-base,#a2a9b1);padding:0.2em;text-align:center;line-height:1.4em;font-size:88%;border-collapse:collapse;display:table}body.skin-minerva .mw-parser-output .sidebar{display:table!important;float:right!important;margin:0.5em 0 1em 1em!important}.mw-parser-output .sidebar-subgroup{width:100%;margin:0;border-spacing:0}.mw-parser-output .sidebar-left{float:left;clear:left;margin:0.5em 1em 1em 0}.mw-parser-output .sidebar-none{float:none;clear:both;margin:0.5em 1em 1em 0}.mw-parser-output .sidebar-outer-title{padding:0 0.4em 0.2em;font-size:125%;line-height:1.2em;font-weight:bold}.mw-parser-output .sidebar-top-image{padding:0.4em}.mw-parser-output .sidebar-top-caption,.mw-parser-output .sidebar-pretitle-with-top-image,.mw-parser-output .sidebar-caption{padding:0.2em 0.4em 0;line-height:1.2em}.mw-parser-output .sidebar-pretitle{padding:0.4em 0.4em 0;line-height:1.2em}.mw-parser-output .sidebar-title,.mw-parser-output .sidebar-title-with-pretitle{padding:0.2em 0.8em;font-size:145%;line-height:1.2em}.mw-parser-output .sidebar-title-with-pretitle{padding:0.1em 0.4em}.mw-parser-output .sidebar-image{padding:0.2em 0.4em 0.4em}.mw-parser-output .sidebar-heading{padding:0.1em 0.4em}.mw-parser-output .sidebar-content{padding:0 0.5em 0.4em}.mw-parser-output .sidebar-content-with-subgroup{padding:0.1em 0.4em 0.2em}.mw-parser-output .sidebar-above,.mw-parser-output .sidebar-below{padding:0.3em 0.8em;font-weight:bold}.mw-parser-output .sidebar-collapse .sidebar-above,.mw-parser-output .sidebar-collapse .sidebar-below{border-top:1px solid #aaa;border-bottom:1px solid #aaa}.mw-parser-output .sidebar-navbar{text-align:right;font-size:115%;padding:0 0.4em 0.4em}.mw-parser-output .sidebar-list-title{padding:0 0.4em;text-align:left;font-weight:bold;line-height:1.6em;font-size:105%}.mw-parser-output .sidebar-list-title-c{padding:0 0.4em;text-align:center;margin:0 3.3em}@media(max-width:640px){body.mediawiki .mw-parser-output .sidebar{width:100%!important;clear:both;float:none!important;margin-left:0!important;margin-right:0!important}}body.skin--responsive .mw-parser-output .sidebar a>img{max-width:none!important}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sidebar:not(.notheme) .sidebar-list-title,html.skin-theme-clientpref-night .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle{background:transparent!important}html.skin-theme-clientpref-night .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle a{color:var(--color-progressive)!important}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sidebar:not(.notheme) .sidebar-list-title,html.skin-theme-clientpref-os .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle{background:transparent!important}html.skin-theme-clientpref-os .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle a{color:var(--color-progressive)!important}}@media print{body.ns-0 .mw-parser-output .sidebar{display:none!important}}</style><table class="sidebar sidebar-collapse nomobile nowraplinks"><tbody><tr><th class="sidebar-title"><a href="/wiki/OSI_model" title="OSI model">OSI model</a><br /><span style="font-size:80%;">by <a href="/wiki/Abstraction_layer" title="Abstraction layer">layer</a></span></th></tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="color: var(--color-base)">7.  <a href="/wiki/Application_layer" title="Application layer">Application layer</a></div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/Network_News_Transfer_Protocol" title="Network News Transfer Protocol">NNTP</a></li> <li><a href="/wiki/Session_Initiation_Protocol" title="Session Initiation Protocol">SIP</a></li> <li><a href="/wiki/Simple_Sensor_Interface_protocol" title="Simple Sensor Interface protocol">SSI</a></li> <li><a href="/wiki/Domain_Name_System" title="Domain Name System">DNS</a></li> <li><a href="/wiki/File_Transfer_Protocol" title="File Transfer Protocol">FTP</a></li> <li><a href="/wiki/Gopher_(protocol)" title="Gopher (protocol)">Gopher</a></li> <li><a href="/wiki/Hypertext_Transfer_Protocol" class="mw-redirect" title="Hypertext Transfer Protocol">HTTP</a> (<a href="/wiki/HTTP/3" title="HTTP/3">HTTP/3</a>)</li> <li><a href="/wiki/Network_File_System" title="Network File System">NFS</a></li> <li><a href="/wiki/Network_Time_Protocol" title="Network Time Protocol">NTP</a></li> <li><a href="/wiki/Short_Message_Peer-to-Peer" title="Short Message Peer-to-Peer">SMPP</a></li> <li><a href="/wiki/Secure_Shell" title="Secure Shell">SSH</a></li> <li><a href="/wiki/Simple_Mail_Transfer_Protocol" title="Simple Mail Transfer Protocol">SMTP</a></li> <li><a href="/wiki/Simple_Network_Management_Protocol" title="Simple Network Management Protocol">SNMP</a></li> <li><a href="/wiki/Telnet" title="Telnet">Telnet</a></li> <li><a href="/wiki/Dynamic_Host_Configuration_Protocol" title="Dynamic Host Configuration Protocol">DHCP</a></li> <li><a href="/wiki/NETCONF" title="NETCONF">NETCONF</a></li> <li><i><a href="/wiki/Category:Application_layer_protocols" title="Category:Application layer protocols">more....</a></i></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="color: var(--color-base)">6.  <a href="/wiki/Presentation_layer" title="Presentation layer">Presentation layer</a></div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/MIME" title="MIME">MIME</a></li> <li><a href="/wiki/External_Data_Representation" title="External Data Representation">XDR</a></li> <li><a href="/wiki/ASN.1" title="ASN.1">ASN.1</a></li> <li><a href="/wiki/ASCII" title="ASCII">ASCII</a></li> <li><a href="/wiki/Transport_Layer_Security" title="Transport Layer Security">TLS</a></li> <li><a href="/wiki/Pretty_Good_Privacy" title="Pretty Good Privacy">PGP</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="color: var(--color-base)">5.  <a href="/wiki/Session_layer" title="Session layer">Session layer</a></div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/Named_pipe" title="Named pipe">Named pipe</a></li> <li><a href="/wiki/NetBIOS" title="NetBIOS">NetBIOS</a></li> <li><a href="/wiki/Session_Announcement_Protocol" title="Session Announcement Protocol">SAP</a></li> <li><a href="/wiki/Point-to-Point_Tunneling_Protocol" title="Point-to-Point Tunneling Protocol">PPTP</a></li> <li><a href="/wiki/Real-time_Transport_Protocol" title="Real-time Transport Protocol">RTP</a></li> <li><a href="/wiki/SOCKS" title="SOCKS">SOCKS</a></li> <li>X.225<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="color: var(--color-base)">4.  <a href="/wiki/Transport_layer" title="Transport layer">Transport layer</a></div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/Transmission_Control_Protocol" title="Transmission Control Protocol">TCP</a></li> <li><a href="/wiki/User_Datagram_Protocol" title="User Datagram Protocol">UDP</a></li> <li><a href="/wiki/Stream_Control_Transmission_Protocol" title="Stream Control Transmission Protocol">SCTP</a></li> <li><a href="/wiki/Datagram_Congestion_Control_Protocol" title="Datagram Congestion Control Protocol">DCCP</a></li> <li><a href="/wiki/QUIC" title="QUIC">QUIC</a></li> <li><a href="/wiki/IPX/SPX" title="IPX/SPX">SPX</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="color: var(--color-base)">3.  <a href="/wiki/Network_layer" title="Network layer">Network layer</a></div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/Internet_Protocol" title="Internet Protocol">IP</a> <ul><li><a href="/wiki/IPv4" title="IPv4">IPv4</a></li> <li><a href="/wiki/IPv6" title="IPv6">IPv6</a></li></ul></li> <li><a href="/wiki/Internet_Control_Message_Protocol" title="Internet Control Message Protocol">ICMP</a> (<a href="/wiki/ICMPv6" title="ICMPv6">ICMPv6</a>)</li> <li><a href="/wiki/IPsec" title="IPsec">IPsec</a></li> <li><a href="/wiki/Internet_Group_Management_Protocol" title="Internet Group Management Protocol">IGMP</a></li> <li><a href="/wiki/Internetwork_Packet_Exchange" title="Internetwork Packet Exchange">IPX</a></li> <li><a href="/wiki/IS-IS" title="IS-IS">IS-IS</a></li> <li><a href="/wiki/AppleTalk" title="AppleTalk">AppleTalk</a></li> <li><a href="/wiki/X.25" title="X.25">X.25</a></li> <li><a href="/wiki/Packet_Layer_Protocol" title="Packet Layer Protocol">PLP</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="color: var(--color-base)">2.  <a class="mw-selflink selflink">Data link layer</a></div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/Asynchronous_Transfer_Mode" title="Asynchronous Transfer Mode">ATM</a></li> <li><a href="/wiki/Address_Resolution_Protocol" title="Address Resolution Protocol">ARP</a></li> <li><a href="/wiki/Synchronous_Data_Link_Control" title="Synchronous Data Link Control">SDLC</a></li> <li><a href="/wiki/High-Level_Data_Link_Control" title="High-Level Data Link Control">HDLC</a></li> <li><a href="/wiki/Serial_Line_Internet_Protocol#CSLIP" title="Serial Line Internet Protocol">CSLIP</a></li> <li><a href="/wiki/Serial_Line_Internet_Protocol" title="Serial Line Internet Protocol">SLIP</a></li> <li><a href="/wiki/Generic_Framing_Procedure" title="Generic Framing Procedure">GFP</a></li> <li><a href="/wiki/Parallel_Line_Internet_Protocol" title="Parallel Line Internet Protocol">PLIP</a></li> <li><a href="/wiki/IEEE_802.2" title="IEEE 802.2">IEEE 802.2</a></li> <li><a href="/wiki/Logical_link_control" title="Logical link control">LLC</a></li> <li><a href="/wiki/Medium_access_control" title="Medium access control">MAC</a></li> <li><a href="/wiki/Layer_2_Tunneling_Protocol" title="Layer 2 Tunneling Protocol">L2TP</a></li> <li><a href="/wiki/IEEE_802.3" title="IEEE 802.3">IEEE 802.3</a></li> <li><a href="/wiki/Frame_Relay" title="Frame Relay">Frame Relay</a></li> <li><a href="/wiki/G.hn" title="G.hn">ITU-T G.hn DLL</a></li> <li><a href="/wiki/Point-to-Point_Protocol" title="Point-to-Point Protocol">PPP</a></li> <li><a href="/wiki/X.25" title="X.25">X.25</a> <a href="/wiki/LAPB" title="LAPB">LAPB</a></li> <li><a href="/wiki/Link_Access_Procedure_for_Frame_Relay" title="Link Access Procedure for Frame Relay">Q.922 LAPF</a></li> <li><a href="/wiki/IEEE_802.11" title="IEEE 802.11">IEEE 802.11</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="color: var(--color-base)">1.  <a href="/wiki/Physical_layer" title="Physical layer">Physical layer</a></div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/RS-232" title="RS-232">RS-232</a></li> <li><a href="/wiki/RS-449" title="RS-449">RS-449</a></li> <li><a href="/wiki/List_of_ITU-T_V-series_recommendations" title="List of ITU-T V-series recommendations">ITU-T V-Series</a></li> <li><a href="/wiki/I.430" title="I.430">I.430</a></li> <li><a href="/wiki/I.431" title="I.431">I.431</a></li> <li><a href="/wiki/Plesiochronous_digital_hierarchy" title="Plesiochronous digital hierarchy">PDH</a></li> <li><a href="/wiki/Synchronous_optical_networking" title="Synchronous optical networking">SONET/SDH</a></li> <li><a href="/wiki/Passive_optical_network" title="Passive optical network">PON</a></li> <li><a href="/wiki/Optical_Transport_Network" class="mw-redirect" title="Optical Transport Network">OTN</a></li> <li><a href="/wiki/Digital_subscriber_line" title="Digital subscriber line">DSL</a></li> <li><a href="/wiki/IEEE_802.3" title="IEEE 802.3">IEEE 802.3</a></li> <li><a href="/wiki/IEEE_802.11" title="IEEE 802.11">IEEE 802.11</a></li> <li><a href="/wiki/IEEE_802.15" title="IEEE 802.15">IEEE 802.15</a></li> <li><a href="/wiki/IEEE_802.16" title="IEEE 802.16">IEEE 802.16</a></li> <li><a href="/wiki/IEEE_1394" title="IEEE 1394">IEEE 1394</a></li> <li><a href="/wiki/G.hn" title="G.hn">ITU-T G.hn PHY</a></li> <li><a href="/wiki/USB" title="USB">USB</a></li> <li><a href="/wiki/Bluetooth" title="Bluetooth">Bluetooth</a></li></ul></div></div></td> </tr><tr><td class="sidebar-navbar"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:OSI_model" title="Template:OSI model"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:OSI_model" title="Template talk:OSI model"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:OSI_model" title="Special:EditPage/Template:OSI model"><abbr title="Edit this template">e</abbr></a></li></ul></div></td></tr></tbody></table> <p>The <b>data link layer</b>, or <b>layer 2</b>, is the second layer of the seven-layer <a href="/wiki/OSI_model" title="OSI model">OSI model</a> of <a href="/wiki/Computer_network" title="Computer network">computer networking</a>. This layer is the protocol layer that transfers data between nodes on a <a href="/wiki/Network_segment" title="Network segment">network segment</a> across the <a href="/wiki/Physical_layer" title="Physical layer">physical layer</a>.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> The data link layer provides the functional and procedural means to <a href="/wiki/Transfer_(computing)" class="mw-redirect" title="Transfer (computing)">transfer</a> data between network entities and may also provide the means to detect and possibly correct errors that can occur in the physical layer. </p><p>The data link layer is concerned with local delivery of <a href="/wiki/Frame_(networking)" title="Frame (networking)">frames</a> between nodes on the same level of the network. Data-link frames, as these <a href="/wiki/Protocol_data_unit" title="Protocol data unit">protocol data units</a> are called, do not cross the boundaries of a local area network. Inter-network routing and global addressing are higher-layer functions, allowing data-link protocols to focus on local delivery, addressing, and media arbitration. In this way, the data link layer is analogous to a neighborhood traffic cop; it endeavors to arbitrate between parties contending for access to a medium, without concern for their ultimate destination. When devices attempt to use a medium simultaneously, frame collisions occur. Data-link protocols specify how devices detect and recover from such collisions, and may provide mechanisms to reduce or prevent them. </p><p>Examples of data link protocols are <a href="/wiki/Ethernet" title="Ethernet">Ethernet</a>, the <a href="/wiki/IEEE_802.11" title="IEEE 802.11">IEEE 802.11</a> WiFi protocols, <a href="/wiki/Asynchronous_Transfer_Mode" title="Asynchronous Transfer Mode">ATM</a> and <a href="/wiki/Frame_Relay" title="Frame Relay">Frame Relay</a>. In the <a href="/wiki/Internet_Protocol_Suite" class="mw-redirect" title="Internet Protocol Suite">Internet Protocol Suite</a> (TCP/IP), the data link layer functionality is contained within the <a href="/wiki/Link_layer" title="Link layer">link layer</a>, the lowest layer of the descriptive model, which is assumed to be independent of physical infrastructure. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Function">Function</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=1" title="Edit section: Function"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The data link provides for the transfer of <a href="/wiki/Data_frame" class="mw-redirect" title="Data frame">data frames</a> between hosts connected to the physical link. Within the semantics of the OSI network architecture, the protocols of the data link layer respond to service requests from the <a href="/wiki/Network_layer" title="Network layer">network layer</a>, and perform their function by issuing service requests to the <a href="/wiki/Physical_layer" title="Physical layer">physical layer</a>. That transfer can be <a href="/wiki/Reliability_(computer_networking)" title="Reliability (computer networking)">reliable or unreliable</a>; many data link protocols do not have acknowledgments of successful frame reception and acceptance, and some data link protocols might not even perform any check for transmission errors. In those cases, higher-level protocols must provide <a href="/wiki/Flow_control_(data)" title="Flow control (data)">flow control</a>, error checking, acknowledgments, and retransmission. </p><p>The frame header contains the source and destination addresses that indicate which device originated the frame and which device is expected to receive and process it. In contrast to the hierarchical and routable addresses of the network layer, layer 2 addresses are flat, meaning that no part of the address can be used to identify the logical or physical group to which the address belongs. </p><p>In some networks, such as <a href="/wiki/IEEE_802" title="IEEE 802">IEEE 802</a> local area networks, the data link layer is described in more detail with <a href="/wiki/Media_access_control" class="mw-redirect" title="Media access control">media access control</a> (MAC) and <a href="/wiki/Logical_link_control" title="Logical link control">logical link control</a> (LLC) sublayers; this means that the <a href="/wiki/IEEE_802.2" title="IEEE 802.2">IEEE 802.2</a> LLC protocol can be used with all of the IEEE 802 MAC layers, such as Ethernet, <a href="/wiki/Token_Ring" title="Token Ring">Token Ring</a>, <a href="/wiki/IEEE_802.11" title="IEEE 802.11">IEEE 802.11</a>, etc., as well as with some non-802 MAC layers such as <a href="/wiki/FDDI" class="mw-redirect" title="FDDI">FDDI</a>. Other data-link-layer protocols, such as <a href="/wiki/High-Level_Data_Link_Control" title="High-Level Data Link Control">HDLC</a>, are specified to include both sublayers, although some other protocols, such as <a href="/wiki/Cisco_HDLC" title="Cisco HDLC">Cisco HDLC</a>, use HDLC's low-level framing as a MAC layer in combination with a different LLC layer. In the <a href="/wiki/ITU-T" title="ITU-T">ITU-T</a> <a href="/wiki/G.hn" title="G.hn">G.hn</a> standard, which provides a way to create a high-speed (up to 1 Gigabit/s) <a href="/wiki/Local_area_network" title="Local area network">local area network</a> using existing home wiring (<a href="/wiki/Power_line_communication" class="mw-redirect" title="Power line communication">power lines</a>, phone lines and <a href="/wiki/Ethernet_over_coax" title="Ethernet over coax">coaxial cables</a>), the data link layer is divided into three sub-layers (application protocol convergence, logical link control and media access control). </p> <div class="mw-heading mw-heading2"><h2 id="Sublayers">Sublayers</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=2" title="Edit section: Sublayers"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The data link layer is often divided into two sublayers: <i><a href="/wiki/Logical_link_control" title="Logical link control">logical link control</a></i> (LLC) and <i><a href="/wiki/Media_access_control" class="mw-redirect" title="Media access control">media access control</a></i> (MAC).<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Logical_link_control_sublayer">Logical link control sublayer</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=3" title="Edit section: Logical link control sublayer"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The uppermost sublayer, LLC, <a href="/wiki/Multiplexing" title="Multiplexing">multiplexes</a> protocols running at the top of the data link layer, and optionally provides flow control, acknowledgment, and error notification. The LLC provides addressing and control of the data link. It specifies which mechanisms are to be used for addressing stations over the transmission medium and for controlling the data exchanged between the originator and recipient machines. </p> <div class="mw-heading mw-heading3"><h3 id="Media_access_control_sublayer">Media access control sublayer</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=4" title="Edit section: Media access control sublayer"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>MAC may refer to the sublayer that determines who is allowed to access the media at any one time (e.g. <a href="/wiki/Carrier-sense_multiple_access_with_collision_detection" title="Carrier-sense multiple access with collision detection">CSMA/CD</a>). Other times it refers to a <a href="/wiki/Frame_(networking)" title="Frame (networking)">frame</a> structure delivered based on <a href="/wiki/MAC_address" title="MAC address">MAC addresses</a> inside. </p><p>There are generally two forms of media access control: distributed and centralized.<sup id="cite_ref-Miao_4-0" class="reference"><a href="#cite_note-Miao-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Both of these may be compared to communication between people. In a network made up of people speaking, i.e. a conversation, they will each pause a random amount of time and then attempt to speak again, effectively establishing a long and elaborate game of saying "no, you first". </p><p>The Media Access Control sublayer also performs <a href="/wiki/Frame_synchronization" title="Frame synchronization">frame synchronization</a>, which determines the start and end of each frame of data in the transmission <a href="/wiki/Bitstream" title="Bitstream">bitstream</a>. It entails one of several methods: timing-based detection, character counting, byte stuffing, and bit stuffing. </p> <ul><li>The time-based approach expects a specified amount of time between frames.</li> <li>Character counting tracks the count of remaining characters in the frame header. This method, however, is easily disturbed if this field is corrupted.</li> <li><a href="/wiki/Byte_stuffing" class="mw-redirect" title="Byte stuffing">Byte stuffing</a> precedes the frame with a special byte sequence such as <a href="/wiki/Data_Link_Escape" class="mw-redirect" title="Data Link Escape">DLE</a> <a href="/wiki/Start_Of_Text" class="mw-redirect" title="Start Of Text">STX</a> and succeeds it with DLE <a href="/wiki/End-of-Text_character" title="End-of-Text character">ETX</a>. Appearances of DLE (byte value 0x10) have to be <a href="/wiki/Escape_sequence" title="Escape sequence">escaped</a> with another DLE. The start and stop marks are detected at the receiver and removed as well as the inserted DLE characters.</li> <li>Similarly, <a href="/wiki/Bit_stuffing" title="Bit stuffing">bit stuffing</a> replaces these start and end marks with flags consisting of a special bit pattern (e.g. a 0, six 1 bits and a 0). Occurrences of this bit pattern in the data to be transmitted are avoided by inserting a bit. To use the example where the flag is 01111110, a 0 is inserted after 5 consecutive 1's in the data stream. The flags and the inserted 0's are removed at the receiving end. This makes for arbitrary long frames and easy synchronization for the recipient. The stuffed bit is added even if the following data bit is 0, which could not be mistaken for a <a href="/wiki/Sync_sequence" class="mw-redirect" title="Sync sequence">sync sequence</a>, so that the receiver can unambiguously distinguish stuffed bits from normal bits.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Services">Services</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=5" title="Edit section: Services"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The services provided by the data link layer are: </p> <ul><li>Encapsulation of <a href="/wiki/Network_layer" title="Network layer">network layer</a> data packets into <a href="/wiki/Frame_(telecommunications)" class="mw-redirect" title="Frame (telecommunications)">frames</a></li> <li><a href="/wiki/Frame_synchronization" title="Frame synchronization">Frame synchronization</a></li> <li>In the <a href="/wiki/Logical_link_control" title="Logical link control">logical link control</a> (LLC) sublayer: <ul><li><a href="/wiki/Error_control" class="mw-redirect" title="Error control">Error control</a> (<a href="/wiki/Automatic_repeat_request" title="Automatic repeat request">automatic repeat request</a>, ARQ), in addition to ARQ provided by some <a href="/wiki/Transport-layer_protocol" class="mw-redirect" title="Transport-layer protocol">transport-layer protocols</a>, to <a href="/wiki/Forward_error_correction" class="mw-redirect" title="Forward error correction">forward error correction</a> (FEC) techniques provided on the <a href="/wiki/Physical_layer" title="Physical layer">physical layer</a>, and to error-detection and packet canceling provided at all layers, including the <a href="/wiki/Network_layer" title="Network layer">network layer</a>. Data-link-layer error control (i.e. retransmission of erroneous packets) is provided in wireless networks and <a href="/wiki/ITU-T_V.42" class="mw-redirect" title="ITU-T V.42">V.42</a> telephone network modems, but not in LAN protocols such as <a href="/wiki/Ethernet" title="Ethernet">Ethernet</a>, since bit errors are so uncommon in short wires. In that case, only <a href="/wiki/Error_detection" class="mw-redirect" title="Error detection">error detection</a> and canceling of erroneous packets are provided.</li> <li><a href="/wiki/Flow_control_(data)" title="Flow control (data)">Flow control</a>, in addition to the one provided on the <a href="/wiki/Transport_layer" title="Transport layer">transport layer</a>. Data-link-layer flow control is not used in LAN protocols such as Ethernet, but in modems and wireless networks.</li></ul></li> <li>In the <a href="/wiki/Medium_access_control" title="Medium access control">medium access control</a> (MAC) sublayer: <ul><li><a href="/wiki/Multiple_access_method" class="mw-redirect" title="Multiple access method">Multiple access methods</a> for channel-access control, for example <a href="/wiki/Carrier-sense_multiple_access_with_collision_detection" title="Carrier-sense multiple access with collision detection">CSMA/CD</a> protocols for <a href="/wiki/Collision_detection" title="Collision detection">collision detection</a> and re-transmission in <a href="/wiki/Ethernet" title="Ethernet">Ethernet</a> bus networks and hub networks, or the <a href="/wiki/Carrier-sense_multiple_access_with_collision_avoidance" title="Carrier-sense multiple access with collision avoidance">CSMA/CA</a> protocol for <a href="/wiki/Collision_avoidance" class="mw-redirect" title="Collision avoidance">collision avoidance</a> in wireless networks.</li> <li>Physical addressing (<a href="/wiki/MAC_address" title="MAC address">MAC addressing</a>)</li> <li><a href="/wiki/LAN_switching" class="mw-redirect" title="LAN switching">LAN switching</a> (<a href="/wiki/Packet_switching" title="Packet switching">packet switching</a>), including <a href="/wiki/MAC_filtering" title="MAC filtering">MAC filtering</a>, <a href="/wiki/Spanning_Tree_Protocol" title="Spanning Tree Protocol">Spanning Tree Protocol</a> (STP), <a href="/wiki/Shortest_Path_Bridging" class="mw-redirect" title="Shortest Path Bridging">Shortest Path Bridging</a> (SPB) and <a href="/wiki/TRILL" title="TRILL">TRILL</a> (TRansparent Interconnection of Lots of Links)</li> <li>Data packet queuing or <a href="/wiki/Scheduling_algorithm#In_computer_networks_and_multiplexing" class="mw-redirect" title="Scheduling algorithm">scheduling</a></li> <li><a href="/wiki/Store-and-forward" class="mw-redirect" title="Store-and-forward">Store-and-forward</a> switching or <a href="/wiki/Cut-through_switching" title="Cut-through switching">cut-through switching</a></li> <li><a href="/wiki/Quality_of_service" title="Quality of service">Quality of service</a> (QoS) control</li> <li><a href="/wiki/Virtual_LAN" class="mw-redirect" title="Virtual LAN">Virtual LANs</a> (VLAN)</li></ul></li></ul> <div class="mw-heading mw-heading2"><h2 id="Error_detection_and_correction">Error detection and correction</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=6" title="Edit section: Error detection and correction"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In addition to framing, the data link layer may also detect and recover from transmission errors. For a receiver to detect transmission errors, the sender must add redundant information as an <a href="/wiki/Error_detection_and_correction" title="Error detection and correction">error detection code</a> to the frame sent. When the receiver obtains a frame it verifies whether the received error detection code matches a recomputed error detection code. </p><p>An error detection code can be defined as a function that computes the <span class="texhtml mvar" style="font-style:italic;">r</span> (amount of redundant bits) corresponding to each string of <span class="texhtml mvar" style="font-style:italic;">N</span> total number of bits. The simplest error detection code is the <a href="/wiki/Parity_bit" title="Parity bit">parity bit</a>, which allows a receiver to detect transmission errors that have affected a single bit among the transmitted <span class="texhtml mvar" style="font-style:italic;">N + r</span> bits. If there are multiple flipped bits then the checking method might not be able to detect this on the receiver side. More advanced methods than parity error detection do exist providing higher grades of quality and features. </p> <table class="wikitable floatright"> <tbody><tr> <th>H</th> <th>E</th> <th>L</th> <th>L</th> <th>O </th></tr> <tr> <td>8</td> <td>5</td> <td>12</td> <td>12</td> <td>15 </td></tr></tbody></table> <p>A simple example of how this works using <a href="/wiki/Metadata" title="Metadata">metadata</a> is transmitting the word "HELLO", by encoding each letter as its position in the alphabet. Thus, the letter <i>A</i> is coded as 1, <i>B</i> as 2, and so on as shown in the table on the right. Adding up the resulting numbers yields 8 + 5 + 12 + 12 + 15 = 52, and 5 + 2 = 7 calculates the metadata. Finally, the "8 5 12 12 15 7" numbers sequence is transmitted, which the receiver will see on its end if there are no transmission errors. The receiver knows that the last number received is the error-detecting metadata and that all data before is the message, so the receiver can recalculate the above math and if the metadata matches it can be concluded that the data has been received error-free. Though, if the receiver sees something like a "7 5 12 12 15 7" sequence (first element altered by some error), it can run the check by calculating 7 + 5 + 12 + 12 + 15 = 51 and 5 + 1 = 6, and discard the received data as defective since 6 does not equal 7. </p><p>More sophisticated error detection and correction algorithms are designed to reduce the risk that multiple transmission errors in the data would cancel each other out and go undetected. An algorithm that can even detect if the correct bytes are received but out of order is the <a href="/wiki/Cyclic_redundancy_check" title="Cyclic redundancy check">cyclic redundancy check</a> or CRC. This algorithm is often used in the data link layer. </p> <div class="mw-heading mw-heading2"><h2 id="Protocol_examples">Protocol examples</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=7" title="Edit section: Protocol examples"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1184024115">.mw-parser-output .div-col{margin-top:0.3em;column-width:30em}.mw-parser-output .div-col-small{font-size:90%}.mw-parser-output .div-col-rules{column-rule:1px solid #aaa}.mw-parser-output .div-col dl,.mw-parser-output .div-col ol,.mw-parser-output .div-col ul{margin-top:0}.mw-parser-output .div-col li,.mw-parser-output .div-col dd{page-break-inside:avoid;break-inside:avoid-column}</style><div class="div-col" style="column-width: 30em;"> <ul><li><a href="/wiki/ARCnet" class="mw-redirect" title="ARCnet">ARCnet</a></li> <li><a href="/wiki/Asynchronous_Transfer_Mode" title="Asynchronous Transfer Mode">ATM</a></li> <li><a href="/wiki/Cisco_Discovery_Protocol" title="Cisco Discovery Protocol">Cisco Discovery Protocol</a> (CDP)</li> <li><a href="/wiki/Controller_Area_Network" class="mw-redirect" title="Controller Area Network">Controller Area Network</a> (CAN)</li> <li><a href="/wiki/Econet" title="Econet">Econet</a></li> <li><a href="/wiki/Ethernet" title="Ethernet">Ethernet</a></li> <li><a href="/wiki/Ethernet_Automatic_Protection_Switching" title="Ethernet Automatic Protection Switching">Ethernet Automatic Protection Switching</a> (EAPS)</li> <li><a href="/wiki/Fiber_Distributed_Data_Interface" title="Fiber Distributed Data Interface">Fiber Distributed Data Interface</a> (FDDI)</li> <li><a href="/wiki/Frame_Relay" title="Frame Relay">Frame Relay</a></li> <li><a href="/wiki/High-Level_Data_Link_Control" title="High-Level Data Link Control">High-Level Data Link Control</a> (HDLC)</li> <li><a href="/wiki/IEEE_802.2" title="IEEE 802.2">IEEE 802.2</a> (provides LLC functions to IEEE 802 MAC layers)</li> <li><a href="/wiki/IEEE_802.11" title="IEEE 802.11">IEEE 802.11</a> <a href="/wiki/Wireless_LAN" title="Wireless LAN">wireless LAN</a></li> <li><a href="/wiki/I%C2%B2C" title="I²C">I²C</a></li> <li><a href="/wiki/LattisNet" title="LattisNet">LattisNet</a></li> <li><a href="/wiki/Link_Layer_Discovery_Protocol" title="Link Layer Discovery Protocol">Link Layer Discovery Protocol</a> (LLDP)</li> <li><a href="/wiki/LocalTalk" title="LocalTalk">LocalTalk</a></li> <li><a href="/wiki/MIL-STD-1553" title="MIL-STD-1553">MIL-STD-1553</a></li> <li><a href="/wiki/Multiprotocol_Label_Switching" title="Multiprotocol Label Switching">Multiprotocol Label Switching</a> (MPLS)</li> <li><a href="/wiki/Nortel_Discovery_Protocol" title="Nortel Discovery Protocol">Nortel Discovery Protocol</a> (NDP)</li> <li><a href="/wiki/Point-to-Point_Protocol" title="Point-to-Point Protocol">Point-to-Point Protocol</a> (PPP)</li> <li><a href="/wiki/Profibus" title="Profibus">Profibus</a></li> <li><a href="/wiki/SpaceWire" title="SpaceWire">SpaceWire</a></li> <li>Serial Line Internet Protocol (<a href="/wiki/Serial_Line_Internet_Protocol" title="Serial Line Internet Protocol">SLIP</a>) (obsolete)</li> <li><a href="/wiki/Split_multi-link_trunking" class="mw-redirect" title="Split multi-link trunking">Split multi-link trunking</a> (SMLT)</li> <li><a href="/wiki/IEEE_802.1aq" title="IEEE 802.1aq">IEEE 802.1aq</a> - Shortest Path Bridging</li> <li><a href="/wiki/Spanning_Tree_Protocol" title="Spanning Tree Protocol">Spanning Tree Protocol</a></li> <li><a href="/wiki/StarLan" class="mw-redirect" title="StarLan">StarLan</a></li> <li><a href="/wiki/Token_Ring" title="Token Ring">Token Ring</a></li> <li><a href="/wiki/TRILL" title="TRILL">TRILL</a> (Transparent Interconnection of Lots of Links)</li> <li><a href="/wiki/UDLD" class="mw-redirect" title="UDLD">Unidirectional Link Detection</a> (UDLD)</li> <li><a href="/wiki/UNI/O" title="UNI/O">UNI/O</a></li> <li><a href="/wiki/1-Wire" title="1-Wire">1-Wire</a></li> <li>and most forms of <a href="/wiki/Serial_communication" title="Serial communication">serial communication</a> e.g. <a href="/wiki/USB" title="USB">USB</a>, <a href="/wiki/PCI_Express" title="PCI Express">PCI Express</a>.</li></ul> </div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Bit-sequence_independence" title="Bit-sequence independence">Bit-sequence independence</a></div> <div class="mw-heading mw-heading2"><h2 id="Relation_to_the_TCP/IP_model"><span id="Relation_to_the_TCP.2FIP_model"></span>Relation to the TCP/IP model</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=8" title="Edit section: Relation to the TCP/IP model"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1246091330"><table class="sidebar nomobile nowraplinks hlist"><tbody><tr><th class="sidebar-title"><a href="/wiki/Internet_protocol_suite" title="Internet protocol suite">Internet protocol suite</a></th></tr><tr><th class="sidebar-heading"> <a href="/wiki/Application_layer" title="Application layer">Application layer</a></th></tr><tr><td class="sidebar-content"> <ul><li><a href="/wiki/Border_Gateway_Protocol" title="Border Gateway Protocol">BGP</a></li> <li><a href="/wiki/Dynamic_Host_Configuration_Protocol" title="Dynamic Host Configuration Protocol">DHCP</a> (<a href="/wiki/DHCPv6" title="DHCPv6">v6</a>)</li> <li><a href="/wiki/Domain_Name_System" title="Domain Name System">DNS</a></li> <li><a href="/wiki/File_Transfer_Protocol" title="File Transfer Protocol">FTP</a></li> <li><a href="/wiki/HTTP" title="HTTP">HTTP</a> (<a href="/wiki/HTTP/3" title="HTTP/3">HTTP/3</a>)</li> <li><a href="/wiki/HTTPS" title="HTTPS">HTTPS</a></li> <li><a href="/wiki/Internet_Message_Access_Protocol" title="Internet Message Access Protocol">IMAP</a></li> <li><a href="/wiki/IRC" title="IRC">IRC</a></li> <li><a href="/wiki/Lightweight_Directory_Access_Protocol" title="Lightweight Directory Access Protocol">LDAP</a></li> <li><a href="/wiki/Media_Gateway_Control_Protocol" title="Media Gateway Control Protocol">MGCP</a></li> <li><a href="/wiki/MQTT" title="MQTT">MQTT</a></li> <li><a href="/wiki/Network_News_Transfer_Protocol" title="Network News Transfer Protocol">NNTP</a></li> <li><a href="/wiki/Network_Time_Protocol" title="Network Time Protocol">NTP</a></li> <li><a href="/wiki/Open_Shortest_Path_First" title="Open Shortest Path First">OSPF</a></li> <li><a href="/wiki/Post_Office_Protocol" title="Post Office Protocol">POP</a></li> <li><a href="/wiki/Precision_Time_Protocol" title="Precision Time Protocol">PTP</a></li> <li><a href="/wiki/Open_Network_Computing_Remote_Procedure_Call" class="mw-redirect" title="Open Network Computing Remote Procedure Call">ONC/RPC</a></li> <li><a href="/wiki/Real-time_Transport_Protocol" title="Real-time Transport Protocol">RTP</a></li> <li><a href="/wiki/Real_Time_Streaming_Protocol" class="mw-redirect" title="Real Time Streaming Protocol">RTSP</a></li> <li><a href="/wiki/Routing_Information_Protocol" title="Routing Information Protocol">RIP</a></li> <li><a href="/wiki/Session_Initiation_Protocol" title="Session Initiation Protocol">SIP</a></li> <li><a href="/wiki/Simple_Mail_Transfer_Protocol" title="Simple Mail Transfer Protocol">SMTP</a></li> <li><a href="/wiki/Simple_Network_Management_Protocol" title="Simple Network Management Protocol">SNMP</a></li> <li><a href="/wiki/Secure_Shell" title="Secure Shell">SSH</a></li> <li><a href="/wiki/Telnet" title="Telnet">Telnet</a></li> <li><a href="/wiki/Transport_Layer_Security" title="Transport Layer Security">TLS/SSL</a></li> <li><a href="/wiki/XMPP" title="XMPP">XMPP</a></li> <li><a href="/wiki/Category:Application_layer_protocols" title="Category:Application layer protocols"><i>more...</i></a></li></ul></td> </tr><tr><th class="sidebar-heading"> <a href="/wiki/Transport_layer" title="Transport layer">Transport layer</a></th></tr><tr><td class="sidebar-content"> <ul><li><a href="/wiki/Transmission_Control_Protocol" title="Transmission Control Protocol">TCP</a></li> <li><a href="/wiki/User_Datagram_Protocol" title="User Datagram Protocol">UDP</a></li> <li><a href="/wiki/Datagram_Congestion_Control_Protocol" title="Datagram Congestion Control Protocol">DCCP</a></li> <li><a href="/wiki/Stream_Control_Transmission_Protocol" title="Stream Control Transmission Protocol">SCTP</a></li> <li><a href="/wiki/Resource_Reservation_Protocol" title="Resource Reservation Protocol">RSVP</a></li> <li><a href="/wiki/QUIC" title="QUIC">QUIC</a></li> <li><a href="/wiki/Category:Transport_layer_protocols" title="Category:Transport layer protocols"><i>more...</i></a></li></ul></td> </tr><tr><th class="sidebar-heading"> <a href="/wiki/Internet_layer" title="Internet layer">Internet layer</a></th></tr><tr><td class="sidebar-content"> <ul><li><a href="/wiki/Internet_Protocol" title="Internet Protocol">IP</a> <ul><li><a href="/wiki/IPv4" title="IPv4">v4</a></li> <li><a href="/wiki/IPv6" title="IPv6">v6</a></li></ul></li> <li><a href="/wiki/Internet_Control_Message_Protocol" title="Internet Control Message Protocol">ICMP</a> (<a href="/wiki/ICMPv6" title="ICMPv6">v6</a>)</li> <li><a href="/wiki/Neighbor_Discovery_Protocol" title="Neighbor Discovery Protocol">NDP</a></li> <li><a href="/wiki/Explicit_Congestion_Notification" title="Explicit Congestion Notification">ECN</a></li> <li><a href="/wiki/Internet_Group_Management_Protocol" title="Internet Group Management Protocol">IGMP</a></li> <li><a href="/wiki/IPsec" title="IPsec">IPsec</a></li> <li><a href="/wiki/Category:Internet_layer_protocols" title="Category:Internet layer protocols"><i>more...</i></a></li></ul></td> </tr><tr><th class="sidebar-heading"> <a href="/wiki/Link_layer" title="Link layer">Link layer</a></th></tr><tr><td class="sidebar-content"> <ul><li><a href="/wiki/Address_Resolution_Protocol" title="Address Resolution Protocol">ARP</a></li> <li><a href="/wiki/Tunneling_protocol" title="Tunneling protocol">Tunnels</a></li> <li><a href="/wiki/Point-to-Point_Protocol" title="Point-to-Point Protocol">PPP</a></li> <li><a href="/wiki/Medium_access_control" title="Medium access control">MAC</a></li> <li><a href="/wiki/Category:Link_protocols" title="Category:Link protocols"><i>more...</i></a></li></ul></td> </tr><tr><td class="sidebar-navbar"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Internet_protocol_suite" title="Template:Internet protocol suite"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Internet_protocol_suite" title="Template talk:Internet protocol suite"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Internet_protocol_suite" title="Special:EditPage/Template:Internet protocol suite"><abbr title="Edit this template">e</abbr></a></li></ul></div></td></tr></tbody></table> <p>In the <a href="/wiki/Internet_Protocol_Suite" class="mw-redirect" title="Internet Protocol Suite">Internet Protocol Suite</a> (TCP/IP), OSI's data link layer functionality is contained within its lowest layer, the <a href="/wiki/Link_layer" title="Link layer">link layer</a>. The TCP/IP link layer has the operating scope of the link a host is connected to, and only concerns itself with hardware issues to the point of obtaining hardware (MAC) addresses for locating hosts on the link and transmitting data frames onto the link. The link-layer functionality was described in RFC 1122 and is defined differently than the data link layer of OSI, and encompasses all methods that affect the local link. </p><p>The TCP/IP model is not a top-down comprehensive design reference for networks. It was formulated for the purpose of illustrating the logical groups and scopes of functions needed in the design of the suite of internetworking protocols of TCP/IP, as needed for the operation of the Internet. In general, direct or strict comparisons of the OSI and TCP/IP models should be avoided, because the layering in TCP/IP is not a principal design criterion and in general, considered to be "harmful" (RFC 3439). In particular, TCP/IP does not dictate a strict hierarchical sequence of encapsulation requirements, as is attributed to OSI protocols. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=9" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/ALOHAnet#ALOHA_protocol" title="ALOHAnet">ALOHAnet § ALOHA protocol</a></li> <li><a href="/wiki/Open_Data-Link_Interface" title="Open Data-Link Interface">ODI</a></li> <li><a href="/wiki/Network_Driver_Interface_Specification" title="Network Driver Interface Specification">NDIS</a></li> <li><a href="/wiki/SANA-II" class="mw-redirect" title="SANA-II">SANA-II</a> – Standard <a href="/wiki/Amiga" title="Amiga">Amiga</a> Networking Architecture, version 2</li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=10" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.itu.int/rec/T-REC-X.225-199511-I/en">"X.225 : Information technology – Open Systems Interconnection – Connection-oriented Session protocol: Protocol specification"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210201064044/https://www.itu.int/rec/T-REC-X.225-199511-I/en">Archived</a> from the original on February 1, 2021<span class="reference-accessdate">. Retrieved <span class="nowrap">March 10,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=X.225+%3A+Information+technology+%E2%80%93+Open+Systems+Interconnection+%E2%80%93+Connection-oriented+Session+protocol%3A+Protocol+specification&rft_id=https%3A%2F%2Fwww.itu.int%2Frec%2FT-REC-X.225-199511-I%2Fen&rfr_id=info%3Asid%2Fen.wikipedia.org%3AData+link+layer" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20100218075030/http://www.accel-networks.com/blog/2009/09/what-is-layer-2-and-why-should-you-care.html">"What is layer 2, and Why Should You Care?"</a>. accel-networks.com. Archived from <a rel="nofollow" class="external text" href="http://www.accel-networks.com/blog/2009/09/what-is-layer-2-and-why-should-you-care.html">the original</a> on February 18, 2010<span class="reference-accessdate">. Retrieved <span class="nowrap">September 29,</span> 2009</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=What+is+layer+2%2C+and+Why+Should+You+Care%3F&rft.pub=accel-networks.com&rft_id=http%3A%2F%2Fwww.accel-networks.com%2Fblog%2F2009%2F09%2Fwhat-is-layer-2-and-why-should-you-care.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AData+link+layer" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRegis_J._Bates_and_Donald_W._Gregory2007" class="citation book cs1">Regis J. Bates and Donald W. Gregory (2007). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=eq1kRHdyXSUC&pg=PA45"><i>Voice & data communications handbook</i></a> (5th ed.). McGraw-Hill Professional. p. 45. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-07-226335-0" title="Special:BookSources/978-0-07-226335-0"><bdi>978-0-07-226335-0</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Voice+%26+data+communications+handbook&rft.pages=45&rft.edition=5th&rft.pub=McGraw-Hill+Professional&rft.date=2007&rft.isbn=978-0-07-226335-0&rft.au=Regis+J.+Bates+and+Donald+W.+Gregory&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3Deq1kRHdyXSUC%26pg%3DPA45&rfr_id=info%3Asid%2Fen.wikipedia.org%3AData+link+layer" class="Z3988"></span></span> </li> <li id="cite_note-Miao-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-Miao_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGuowang_MiaoGuocong_Song2014" class="citation book cs1"><a href="/wiki/Guowang_Miao" title="Guowang Miao">Guowang Miao</a>; Guocong Song (2014). <i>Energy and spectrum efficient wireless network design</i>. <a href="/wiki/Cambridge_University_Press" title="Cambridge University Press">Cambridge University Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1107039889" title="Special:BookSources/978-1107039889"><bdi>978-1107039889</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Energy+and+spectrum+efficient+wireless+network+design&rft.pub=Cambridge+University+Press&rft.date=2014&rft.isbn=978-1107039889&rft.au=Guowang+Miao&rft.au=Guocong+Song&rfr_id=info%3Asid%2Fen.wikipedia.org%3AData+link+layer" class="Z3988"></span></span> </li> </ol></div></div> <style data-mw-deduplicate="TemplateStyles:r1239549316">.mw-parser-output .refbegin{margin-bottom:0.5em}.mw-parser-output .refbegin-hanging-indents>ul{margin-left:0}.mw-parser-output .refbegin-hanging-indents>ul>li{margin-left:0;padding-left:3.2em;text-indent:-3.2em}.mw-parser-output .refbegin-hanging-indents ul,.mw-parser-output .refbegin-hanging-indents ul li{list-style:none}@media(max-width:720px){.mw-parser-output .refbegin-hanging-indents>ul>li{padding-left:1.6em;text-indent:-1.6em}}.mw-parser-output .refbegin-columns{margin-top:0.3em}.mw-parser-output .refbegin-columns ul{margin-top:0}.mw-parser-output .refbegin-columns li{page-break-inside:avoid;break-inside:avoid-column}@media screen{.mw-parser-output .refbegin{font-size:90%}}</style><div class="refbegin" style=""> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFS._Tanenbaum2005" class="citation book cs1">S. Tanenbaum, Andrew (2005). <a rel="nofollow" class="external text" href="https://archive.org/details/isbn_9788177581652"><i>Computer Networks</i></a> (4th ed.). 482,F.I.E., <a href="/wiki/Patparganj" title="Patparganj">Patparganj</a>, Delhi 110 092: Dorling Kindersley(India)Pvt. Ltd.,licenses of Pearson Education in South Asia. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/81-7758-165-1" title="Special:BookSources/81-7758-165-1"><bdi>81-7758-165-1</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Computer+Networks&rft.place=482%2CF.I.E.%2C+Patparganj%2C+Delhi+110+092&rft.edition=4th&rft.pub=Dorling+Kindersley%28India%29Pvt.+Ltd.%2Clicenses+of+Pearson+Education+in+South+Asia&rft.date=2005&rft.isbn=81-7758-165-1&rft.aulast=S.+Tanenbaum&rft.aufirst=Andrew&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fisbn_9788177581652&rfr_id=info%3Asid%2Fen.wikipedia.org%3AData+link+layer" class="Z3988"></span><span class="cs1-maint citation-comment"><code class="cs1-code">{{<a href="/wiki/Template:Cite_book" title="Template:Cite book">cite book</a>}}</code>: CS1 maint: location (<a href="/wiki/Category:CS1_maint:_location" title="Category:CS1 maint: location">link</a>)</span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOdom2013" class="citation book cs1">Odom, Wendel (2013). <i>CCENT/CCNA ICND1 100-101, CCENT Official cert guide</i>. Paul Boger, cisco press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1-58714-385-4" title="Special:BookSources/978-1-58714-385-4"><bdi>978-1-58714-385-4</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=CCENT%2FCCNA+ICND1+100-101%2C+CCENT+Official+cert+guide&rft.pub=Paul+Boger%2C+cisco+press&rft.date=2013&rft.isbn=978-1-58714-385-4&rft.aulast=Odom&rft.aufirst=Wendel&rfr_id=info%3Asid%2Fen.wikipedia.org%3AData+link+layer" class="Z3988"></span></li></ul> </div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Data_link_layer&action=edit&section=11" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1235681985">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r1237033735">@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}</style><div class="side-box side-box-right plainlinks sistersitebox"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style> <div class="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png" decoding="async" width="30" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/45px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/59px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span></div> <div class="side-box-text plainlist">Wikimedia Commons has media related to <span style="font-weight: bold; font-style: italic;"><a href="https://commons.wikimedia.org/wiki/Category:Data_link_layer" class="extiw" title="commons:Category:Data link layer">Data link layer</a></span>.</div></div> </div> <ul><li><a rel="nofollow" class="external text" href="http://www.codeproject.com/Articles/57072/DataLink-Simulator">DataLink layer simulation, written in C#</a></li> <li><a rel="nofollow" class="external text" href="http://www.cs.gmu.edu/~huangyih/656/error.pdf">DataLink Layer, Part 2: Error Detection and Correction</a></li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Data_link_layer&oldid=1243885558">https://en.wikipedia.org/w/index.php?title=Data_link_layer&oldid=1243885558</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:OSI_model" title="Category:OSI model">OSI model</a></li><li><a href="/wiki/Category:Link_protocols" title="Category:Link protocols">Link protocols</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Use_American_English_from_March_2019" title="Category:Use American English from March 2019">Use American English from March 2019</a></li><li><a href="/wiki/Category:All_Wikipedia_articles_written_in_American_English" title="Category:All Wikipedia articles written in American English">All Wikipedia articles written in American English</a></li><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_matches_Wikidata" title="Category:Short description matches Wikidata">Short description matches Wikidata</a></li><li><a href="/wiki/Category:Use_mdy_dates_from_March_2019" title="Category:Use mdy dates from March 2019">Use mdy dates from March 2019</a></li><li><a href="/wiki/Category:CS1_maint:_location" title="Category:CS1 maint: location">CS1 maint: location</a></li><li><a href="/wiki/Category:Commons_category_link_from_Wikidata" title="Category:Commons category link from Wikidata">Commons category link from Wikidata</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 3 September 2024, at 22:53<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. By using this site, you agree to the <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use" class="extiw" title="foundation:Special:MyLanguage/Policy:Terms of Use">Terms of Use</a> and <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy" class="extiw" title="foundation:Special:MyLanguage/Policy:Privacy policy">Privacy Policy</a>. Wikipedia® is a registered trademark of the <a rel="nofollow" class="external text" href="https://wikimediafoundation.org/">Wikimedia Foundation, Inc.</a>, a non-profit organization.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-contact"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us">Contact Wikipedia</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/en.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//en.m.wikipedia.org/w/index.php?title=Data_link_layer&mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/static/images/footer/wikimedia-button.svg" width="84" height="29" alt="Wikimedia Foundation" loading="lazy"></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/w/resources/assets/poweredby_mediawiki.svg" alt="Powered by MediaWiki" width="88" height="31" loading="lazy"></a></li> </ul> </footer> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-f69cdc8f6-llpj7","wgBackendResponseTime":150,"wgPageParseReport":{"limitreport":{"cputime":"0.584","walltime":"0.809","ppvisitednodes":{"value":1225,"limit":1000000},"postexpandincludesize":{"value":41051,"limit":2097152},"templateargumentsize":{"value":1384,"limit":2097152},"expansiondepth":{"value":14,"limit":100},"expensivefunctioncount":{"value":4,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":41403,"limit":5000000},"entityaccesscount":{"value":1,"limit":400},"timingprofile":["100.00% 637.818 1 -total"," 25.29% 161.299 1 Template:OSIModel"," 25.22% 160.884 1 Template:Reflist"," 24.20% 154.354 1 Template:Sidebar_with_collapsible_lists"," 18.95% 120.840 2 Template:Cite_web"," 16.78% 107.048 1 Template:Commons_category"," 16.39% 104.544 1 Template:Sister_project"," 16.02% 102.180 1 Template:Side_box"," 10.54% 67.201 1 Template:Short_description"," 9.96% 63.552 2 Template:If_then_show"]},"scribunto":{"limitreport-timeusage":{"value":"0.360","limit":"10.000"},"limitreport-memusage":{"value":5823856,"limit":52428800}},"cachereport":{"origin":"mw-web.codfw.main-f69cdc8f6-bjwd6","timestamp":"20241122142555","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Data link layer","url":"https:\/\/en.wikipedia.org\/wiki\/Data_link_layer","sameAs":"http:\/\/www.wikidata.org\/entity\/Q194134","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q194134","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2002-11-29T12:40:17Z","dateModified":"2024-09-03T22:53:01Z","headline":"second layer of the OSI networking model"}</script> </body> </html>