{"id":4581,"date":"2023-06-16T02:03:08","date_gmt":"2023-06-16T02:03:08","guid":{"rendered":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/?post_type=chapter&#038;p=4581"},"modified":"2025-08-26T04:03:21","modified_gmt":"2025-08-26T04:03:21","slug":"cryptography-apply-it-1","status":"web-only","type":"chapter","link":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/chapter\/cryptography-apply-it-1\/","title":{"raw":"Cryptography: Apply It 1","rendered":"Cryptography: Apply It 1"},"content":{"raw":"<section class=\"textbox learningGoals\">\r\n<ul>\r\n\t<li>Compare ways of encrypting and decrypting data using shared symmetric-key methods<\/li>\r\n\t<li>Understand the basics of public key cryptography, including key pairs, digital signatures, and encryption\/decryption<\/li>\r\n\t<li>Compare the pros and cons of using public key cryptography versus symmetric-key methods<\/li>\r\n<\/ul>\r\n<\/section>\r\n<h2>Cryptographic Chronicles: Embarking on Zuri's Journey to Safeguard Data<\/h2>\r\n<p>Let's revisit Zuri and her college internship. Zuri, a college student who has a passion for cybersecurity, just started a new internship at a local cybersecurity firm. She has just been assigned to the \"Digital Defense League\", a special unit responsible for the protection of the digital space in her area. After her success with helping ensure the safety of three organizations using positional systems and bases, Zuri has been promoted to the cryptography team. Her new role is integral to maintaining the confidentiality and integrity of her companies data. Let's help Zuri navigate various methods of cryptography!<\/p>\r\n<center>\r\n[caption id=\"attachment_6499\" align=\"aligncenter\" width=\"500\"]<img class=\"wp-image-6499\" src=\"https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-300x200.jpg\" alt=\"Woman working on a computer.\" width=\"500\" height=\"334\" \/> Figure 1. Help Zuri navigate these tasks about cryptography[\/caption]\r\n<\/center>\r\n<p>&nbsp;<\/p>\r\n<h3>Substitution Cipher<\/h3>\r\n<p>Zuri's teammate, Alice, has encrypted a message to test her skills using a basic substitution cipher. Given that 'a' has been replaced with 'd', 'b' with 'e', 'c' with 'f' and so forth, Alice's message reads \"lwc\".<\/p>\r\n<section class=\"textbox tryIt\">[ohm2_question hide_question_numbers=1]9537[\/ohm2_question]<\/section>\r\n<p>Being part of the cryptography team, Zuri must analyze the efficiency and practicality of different encryption methods. Let's help her understand a different symmetric-key method.<\/p>\r\n<h3><strong>Transposition Cipher<\/strong><\/h3>\r\n<p>Bob, another member of the \"Digital Defense League\", has been working with transposition ciphers. He's scrambled a word by shifting each character two places to the right, resulting in \"atthec\". He passes the message to Zuri to decode.<\/p>\r\n<section class=\"textbox tryIt\">[ohm2_question hide_question_numbers=1]9538[\/ohm2_question]<\/section>","rendered":"<section class=\"textbox learningGoals\">\n<ul>\n<li>Compare ways of encrypting and decrypting data using shared symmetric-key methods<\/li>\n<li>Understand the basics of public key cryptography, including key pairs, digital signatures, and encryption\/decryption<\/li>\n<li>Compare the pros and cons of using public key cryptography versus symmetric-key methods<\/li>\n<\/ul>\n<\/section>\n<h2>Cryptographic Chronicles: Embarking on Zuri&#8217;s Journey to Safeguard Data<\/h2>\n<p>Let&#8217;s revisit Zuri and her college internship. Zuri, a college student who has a passion for cybersecurity, just started a new internship at a local cybersecurity firm. She has just been assigned to the &#8220;Digital Defense League&#8221;, a special unit responsible for the protection of the digital space in her area. After her success with helping ensure the safety of three organizations using positional systems and bases, Zuri has been promoted to the cryptography team. Her new role is integral to maintaining the confidentiality and integrity of her companies data. Let&#8217;s help Zuri navigate various methods of cryptography!<\/p>\n<div style=\"text-align: center;\">\n<figure id=\"attachment_6499\" aria-describedby=\"caption-attachment-6499\" style=\"width: 500px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-6499\" src=\"https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-300x200.jpg\" alt=\"Woman working on a computer.\" width=\"500\" height=\"334\" srcset=\"https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-300x200.jpg 300w, https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-1024x684.jpg 1024w, https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-768x513.jpg 768w, https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-1536x1025.jpg 1536w, https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-2048x1367.jpg 2048w, https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-1200x801.jpg 1200w, https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-65x43.jpg 65w, https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-225x150.jpg 225w, https:\/\/content-cdn.one.lumenlearning.com\/wp-content\/uploads\/sites\/18\/2023\/06\/10204130\/christina-wocintechchat-com-L85a1k-XqH8-unsplash_50-350x234.jpg 350w\" sizes=\"(max-width: 500px) 100vw, 500px\" \/><figcaption id=\"caption-attachment-6499\" class=\"wp-caption-text\">Figure 1. Help Zuri navigate these tasks about cryptography<\/figcaption><\/figure>\n<\/div>\n<p>&nbsp;<\/p>\n<h3>Substitution Cipher<\/h3>\n<p>Zuri&#8217;s teammate, Alice, has encrypted a message to test her skills using a basic substitution cipher. Given that &#8216;a&#8217; has been replaced with &#8216;d&#8217;, &#8216;b&#8217; with &#8216;e&#8217;, &#8216;c&#8217; with &#8216;f&#8217; and so forth, Alice&#8217;s message reads &#8220;lwc&#8221;.<\/p>\n<section class=\"textbox tryIt\"><iframe loading=\"lazy\" id=\"ohm9537\" class=\"resizable\" src=\"https:\/\/ohm.one.lumenlearning.com\/multiembedq.php?id=9537&theme=lumen&iframe_resize_id=ohm9537&source=tnh\" width=\"100%\" height=\"150\"><\/iframe><\/section>\n<p>Being part of the cryptography team, Zuri must analyze the efficiency and practicality of different encryption methods. Let&#8217;s help her understand a different symmetric-key method.<\/p>\n<h3><strong>Transposition Cipher<\/strong><\/h3>\n<p>Bob, another member of the &#8220;Digital Defense League&#8221;, has been working with transposition ciphers. He&#8217;s scrambled a word by shifting each character two places to the right, resulting in &#8220;atthec&#8221;. He passes the message to Zuri to decode.<\/p>\n<section class=\"textbox tryIt\"><iframe loading=\"lazy\" id=\"ohm9538\" class=\"resizable\" src=\"https:\/\/ohm.one.lumenlearning.com\/multiembedq.php?id=9538&theme=lumen&iframe_resize_id=ohm9538&source=tnh\" width=\"100%\" height=\"150\"><\/iframe><\/section>\n","protected":false},"author":23,"menu_order":11,"template":"","meta":{"_candela_citation":"[]","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"part":2245,"module-header":"apply_it","content_attributions":[],"internal_book_links":[],"video_content":null,"cc_video_embed_content":{"cc_scripts":"","media_targets":[]},"try_it_collection":null,"_links":{"self":[{"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/pressbooks\/v2\/chapters\/4581"}],"collection":[{"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/wp\/v2\/users\/23"}],"version-history":[{"count":11,"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/pressbooks\/v2\/chapters\/4581\/revisions"}],"predecessor-version":[{"id":15675,"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/pressbooks\/v2\/chapters\/4581\/revisions\/15675"}],"part":[{"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/pressbooks\/v2\/parts\/2245"}],"metadata":[{"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/pressbooks\/v2\/chapters\/4581\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/wp\/v2\/media?parent=4581"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/pressbooks\/v2\/chapter-type?post=4581"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/wp\/v2\/contributor?post=4581"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/quantitativereasoning\/wp-json\/wp\/v2\/license?post=4581"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}