{"id":604,"date":"2021-08-22T01:23:19","date_gmt":"2021-08-22T01:23:19","guid":{"rendered":"https:\/\/csiag.eu\/?p=604"},"modified":"2023-01-21T16:44:31","modified_gmt":"2023-01-21T16:44:31","slug":"grundlaeggende-internet-for-dummies","status":"publish","type":"post","link":"https:\/\/csiag.eu\/da\/blog\/2021\/08\/22\/internet-grundlagen-fuer-dummies\/","title":{"rendered":"Grundl\u00e6ggende internet for dummies"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_87_1 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Indholdsfortegnelse<\/p>\n<span class=\"ez-toc-title-toggle\"><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/csiag.eu\/da\/blog\/2021\/08\/22\/internet-grundlagen-fuer-dummies\/#DNS\" >DNS<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/csiag.eu\/da\/blog\/2021\/08\/22\/internet-grundlagen-fuer-dummies\/#Der_Weg_zum_Ziel\" >Vejen til m\u00e5let<\/a><\/li><\/ul><\/nav><\/div>\n<span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">L\u00e6setid<\/span> <span class=\"rt-time\"> 2<\/span> <span class=\"rt-label rt-postfix\">minutter<\/span><\/span>\n<p class=\"wp-block-paragraph\">Det grundl\u00e6ggende for at forst\u00e5 internettet - lad os spille dumme ... - Enhver, der har set Feuerzangenbowle med Heinz R\u00fchmann, vil v\u00e6re bekendt med dette ordsprog om dampmaskinens funktion, der diskuteres der.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Alle, der ikke kender det, har i det mindste h\u00f8rt om Google, som nok er en af de mest brugte s\u00f8gemaskiner p\u00e5 internettet i dag.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Men hvordan fungerer det, at hvis du <em>google.com<\/em> ogs\u00e5 lander p\u00e5 denne s\u00f8gemaskine?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Sammenligningen med den gode gamle telefonbog er ganske vist misvisende, men giver et godt grundlag:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Hvis man f\u00f8r i tiden ville finde telefonnummeret til en bekendt, skulle man som minimum bruge navnet og den by, hvor vedkommende boede. Derefter skulle man bruge telefonbogen for den p\u00e5g\u00e6ldende by til at s\u00f8ge efter navnet. Den havde et omr\u00e5denummer, som man skulle s\u00e6tte foran telefonnummeret. Hvis den bekendte ogs\u00e5 hed M\u00fcller, var fornavnet ogs\u00e5 en hj\u00e6lp. Hvis det ogs\u00e5 var et almindeligt navn, var den eneste m\u00e5de at lokalisere \"M\u00fcller\" og finde hans telefonnummer p\u00e5 at kende gaden. Og hvis han boede i et bof\u00e6llesskab, var opkaldsnummeret ogs\u00e5 relevant, selvf\u00f8lgelig forudsat at den person, man ledte efter, boede i Tyskland.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">P\u00e5 internettet vises landekoden, omr\u00e5denummeret og telefonnummeret, f.eks. til viderestilling, som s\u00e5kaldte IP-adresser (Internet Protocol). Alle fire nummerkomponenter, adskilt fra hinanden af en prik, kan hver is\u00e6r have v\u00e6rdier fra 001 ... 255. Google.de har f.eks. adressen 008.008.008.008.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Denne adresse svarer til IPv4-standarden og giver et adresserum p\u00e5 4 milliarder adresser. IPv6-standarden, som i \u00f8jeblikket stadig drives parallelt, muligg\u00f8r et adresserum p\u00e5 lige under en sextillion (3,4 x 10<sup>38<\/sup>).<br><br><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"DNS\"><\/span>DNS<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Tolvcifrede talr\u00e6kker er ikke s\u00e6rligt mindev\u00e6rdige sammenlignet med navne. Det er derfor, der findes en slags telefonbogstjeneste p\u00e5 internettet, DNS (Domain Name Server). Disse bruger indtastningen af navnet <em>Google.com<\/em> til den ovenn\u00e6vnte nummersekvens 008.008.008.008 eller 8.8.8.8.8.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Lad os se p\u00e5 den rute, en s\u00f8gning tager, n\u00e5r nogen er i Cuxhaven <em>Google.com<\/em> i adresselinjen i browseren p\u00e5 en computer. Kommandoen <em>traceroute<\/em> (f\u00f8lg ruten) under Mac OS, <em>tracert<\/em> under Windows.<br><br><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Der_Weg_zum_Ziel\"><\/span>Vejen til m\u00e5let<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><em>traceroute 8.8.8.8<\/em> eller <em>traceroute google.com<\/em><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Computer 192.168.1.16 via WLAN -&gt; Router (intern DNS; f.eks. AVM FritzBox) - 192.168.1.1 - 1,068 ms<\/li>\n\n\n\n<li>Router -&gt; D - Kassel - 88.134.189.230 - 12.891 ms<\/li>\n\n\n\n<li>-&gt; D - Kassel - 88.134.192.186 - 13.906 ms<\/li>\n\n\n\n<li>-&gt; D - Darmstadt - 145.254.3.62 - 17.076 ms<\/li>\n\n\n\n<li>-&gt; D - Darmstadt - 145.254.2.215 - 17.146 ms<\/li>\n\n\n\n<li>-&gt; USA - CA - Mountain View - 72.14.194.138 - 15.443 ms<\/li>\n\n\n\n<li>-&gt; USA - KS - KansasCity - 8.8.8.8 - 18.787 ms<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Den tid, der kr\u00e6ves for denne rejse over den halve klode, med i alt seks datacentre involveret, er 86,37 ms i alt - et ganske hurtigt svar.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>","protected":false},"excerpt":{"rendered":"<p><span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">L\u00e6setid<\/span> <span class=\"rt-time\"> 2<\/span> <span class=\"rt-label rt-postfix\">minutter<\/span><\/span>Det grundl\u00e6ggende for at forst\u00e5 internettet - lad os spille dumme ... - Enhver, der har set Feuerzangenbowle med Heinz R\u00fchmann, vil kende dette ordsprog om, hvordan dampmaskinen fungerer. Alle, der ikke kender det, har i det mindste h\u00f8rt om Google, som nok er en af de mest brugte s\u00f8gemaskiner p\u00e5 internettet i dag....&nbsp;<a href=\"https:\/\/csiag.eu\/da\/blog\/2021\/08\/22\/internet-grundlagen-fuer-dummies\/\" rel=\"bookmark\">L\u00e6s mere \"<span class=\"screen-reader-text\">Grundl\u00e6ggende internet for dummies<\/span><\/a><\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_lmt_disableupdate":"","_lmt_disable":"","neve_meta_sidebar":"","neve_meta_container":"","neve_meta_enable_content_width":"","neve_meta_content_width":0,"neve_meta_title_alignment":"","neve_meta_author_avatar":"","neve_post_elements_order":"","neve_meta_disable_header":"","neve_meta_disable_footer":"","neve_meta_disable_title":"","footnotes":""},"categories":[360,364],"tags":[1051,1049,1048,576,1050,1052],"class_list":["post-604","post","type-post","status-publish","format-standard","hentry","category-haus-und-garten","category-internet-grundlagen-fuer-dummies","tag-dns","tag-grundlagen","tag-internet","tag-ip","tag-ipv6","tag-traceroute"],"modified_by":"Achim Goerner","_links":{"self":[{"href":"https:\/\/csiag.eu\/da\/wp-json\/wp\/v2\/posts\/604","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/csiag.eu\/da\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/csiag.eu\/da\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/csiag.eu\/da\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/csiag.eu\/da\/wp-json\/wp\/v2\/comments?post=604"}],"version-history":[{"count":0,"href":"https:\/\/csiag.eu\/da\/wp-json\/wp\/v2\/posts\/604\/revisions"}],"wp:attachment":[{"href":"https:\/\/csiag.eu\/da\/wp-json\/wp\/v2\/media?parent=604"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/csiag.eu\/da\/wp-json\/wp\/v2\/categories?post=604"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/csiag.eu\/da\/wp-json\/wp\/v2\/tags?post=604"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}