{"version":"1.0","provider_name":"De Beveiliging van Overheidsberichten","provider_url":"https:\/\/oberman.nl\/boek","author_name":"admin","author_url":"https:\/\/oberman.nl\/boek\/?author=1","title":"De Beveiliging van Overheidsberichten","type":"rich","width":600,"height":338,"html":"<blockquote class=\"wp-embedded-content\" data-secret=\"sr67gqY3V6\"><a href=\"https:\/\/oberman.nl\/boek\/\">De Beveiliging van Overheidsberichten<\/a><\/blockquote><iframe sandbox=\"allow-scripts\" security=\"restricted\" src=\"https:\/\/oberman.nl\/boek\/?embed=true#?secret=sr67gqY3V6\" width=\"600\" height=\"338\" title=\"&#8220;De Beveiliging van Overheidsberichten&#8221; &#8212; De Beveiliging van Overheidsberichten\" data-secret=\"sr67gqY3V6\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\" class=\"wp-embedded-content\"><\/iframe><script>\n\/*! This file is auto-generated *\/\n!function(d,l){\"use strict\";l.querySelector&&d.addEventListener&&\"undefined\"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!\/[^a-zA-Z0-9]\/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret=\"'+t.secret+'\"]'),o=l.querySelectorAll('blockquote[data-secret=\"'+t.secret+'\"]'),c=new RegExp(\"^https?:$\",\"i\"),i=0;i<o.length;i++)o[i].style.display=\"none\";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute(\"style\"),\"height\"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):\"link\"===t.message&&(r=new URL(s.getAttribute(\"src\")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener(\"message\",d.wp.receiveEmbedMessage,!1),l.addEventListener(\"DOMContentLoaded\",function(){for(var e,t,s=l.querySelectorAll(\"iframe.wp-embedded-content\"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute(\"data-secret\"))||(t=Math.random().toString(36).substring(2,12),e.src+=\"#?secret=\"+t,e.setAttribute(\"data-secret\",t)),e.contentWindow.postMessage({message:\"ready\",secret:t},\"*\")},!1)))}(window,document);\n\/\/# sourceURL=https:\/\/oberman.nl\/boek\/wp-includes\/js\/wp-embed.min.js\n<\/script>\n","description":"Het onderwerp \u2018Beveiliging van overheidsberichten\u2019\u00a0is nog steeds actueel, zo ook de uitwerking ervan. Veertig jaar geleden kreeg ik van mijn vader de documentatie van het eerste naoorlogse crypto-apparaat. Hij had dat systeem in de jaren 1947\u00a0\u2013\u00a01949 gemaakt. De documentatie van dat systeem heb ik jarenlang bewaard, omdat hij had aangegeven dat het later erg interessant zou zijn. Het was indertijd\u00a0Staatsgeheim\u00a0en daardoor was er nooit over gepubliceerd.","thumbnail_url":"https:\/\/oberman.nl\/boek\/wp-content\/uploads\/2022\/05\/boek3-edited.jpg","thumbnail_width":1200,"thumbnail_height":900}