{"id":2538,"date":"2019-08-12T10:04:46","date_gmt":"2019-08-12T10:04:46","guid":{"rendered":"http:\/\/teachcomputerscience.com\/?p=530"},"modified":"2024-07-24T11:02:40","modified_gmt":"2024-07-24T11:02:40","slug":"asymmetric-encryption","status":"publish","type":"post","link":"https:\/\/teachcomputerscience.com\/asymmetric-encryption\/","title":{"rendered":"Asymmetric Encryption"},"content":{"rendered":"<div class=\"gb-container gb-container-1798c414 upsell-block\"><div class=\"gb-inside-container\">\n<div class=\"gb-grid-wrapper gb-grid-wrapper-d4aaad39\">\n<div class=\"gb-grid-column gb-grid-column-fb5dfbcc\"><div class=\"gb-container gb-container-fb5dfbcc\"><div class=\"gb-inside-container\">\n\n<h2 class=\"gb-headline gb-headline-93cd47c5 gb-headline-text\">KS3 Encryption Algorithms (14-16 years)<\/h2>\n\n\n\n<ul class=\"wp-block-list\"><li>An editable PowerPoint lesson presentation<\/li><li>Editable revision handouts<\/li><li>A glossary which covers the key terminologies of the module<\/li><li>Topic mindmaps for visualising the key concepts<\/li><li>Printable flashcards to help students engage active recall and confidence-based repetition<\/li><li>A quiz with accompanying answer key to test knowledge and understanding of the module<\/li><\/ul>\n\n\n<div class=\"gb-button-wrapper gb-button-wrapper-adb58505\">\n\n<a class=\"gb-button gb-button-7105bbf6 gb-button-text\" href=\"https:\/\/teachcomputerscience.com\/ks3\/data-representation\/encryption-algorithms\/\">View KS3 Encryption Algorithms Resources<\/a>\n\n<\/div>\n<\/div><\/div><\/div>\n\n<div class=\"gb-grid-column gb-grid-column-0f88b54a\"><div class=\"gb-container gb-container-0f88b54a\"><div class=\"gb-inside-container\">\n\n<h2 class=\"gb-headline gb-headline-93bd04f1 gb-headline-text\">A-Level Compression, Encryption and Hashing (16-18 years)<\/h2>\n\n\n\n<ul class=\"wp-block-list\"><li>An editable PowerPoint lesson presentation<\/li><li>Editable revision handouts<\/li><li>A glossary which covers the key terminologies of the module<\/li><li>Topic mindmaps for visualising the key concepts<\/li><li>Printable flashcards to help students engage active recall and confidence-based repetition<\/li><li>A quiz with accompanying answer key to test knowledge and understanding of the module<\/li><\/ul>\n\n\n<div class=\"gb-button-wrapper gb-button-wrapper-8795cf3f\">\n\n<a class=\"gb-button gb-button-bd725a05 gb-button-text\" href=\"https:\/\/teachcomputerscience.com\/a-level\/exchanging-data\/compression-encryption-and-hashing\/\">View A-Level Compression, Encryption and Hashing Resources<\/a>\n\n<\/div>\n<\/div><\/div><\/div>\n<\/div>\n<\/div><\/div>\n\n\n\n\n<p>Encryption is the process of taking a message and scrambling its contents so that only certain people can look at what\u2019s inside. In this article, we&#8217;re going to focus on asymmetric encryption.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><u>Two Types of Encryption<\/u><\/h2>\n\n\n\n<ul class=\"wp-block-list\"><li><a href=\"http:\/\/teachcomputerscience.com\/symmetric-encryption\/\">Symmetric encryption<\/a><\/li><li>Asymmetric encryption<\/li><\/ul>\n\n\n\n<p><strong>Asymmetric encryption<\/strong> was created to solve the problem brought about by Symmetric encryption.&nbsp; Let\u2019s look at this illustration.&nbsp; User 1 has a sensitive document that he wants to share with User 2.&nbsp; He uses an encryption program to protect his document with a password that he chooses, and then sends the encrypted document to User 2.&nbsp; However, User 2 cannot open the message because he doesn\u2019t know the password that User 1 used to encrypt the document.&nbsp; User 2 doesn\u2019t have the key to open the lock.&nbsp; Now how does User 1 share the password securely with User 2?&nbsp; Sending it through email is risky because others might access the password and use it to decrypt any messages between User 1 and 2.&nbsp; This is why Asymmetric encryption was created.<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"150\" src=\"http:\/\/teachcomputerscience.com\/wp-content\/uploads\/2018\/02\/Asymmetric_encryption_1-300x150.png\" alt=\"Illustration of Asymmetric Encryption.\" class=\"wp-image-5553\" title=\"\" srcset=\"https:\/\/teachcomputerscience.com\/wp-content\/uploads\/2018\/02\/Asymmetric_encryption_1-300x150.png 300w, https:\/\/teachcomputerscience.com\/wp-content\/uploads\/2018\/02\/Asymmetric_encryption_1.png 318w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/figure><\/div>\n\n\n\n<p>Asymmetric encryption can be likened to a mailbox on the street.&nbsp; The mailbox is completely public\u2014anyone who knows its location could go to it and drop in a letter.&nbsp; However, only the owner of the mailbox has a key that allows him to access it and read the letters.<\/p>\n\n\n\n<p>When using asymmetric encryption, both Users 1 and 2 have to generate a key pair on their computers.&nbsp; This is done using the RSA algorithm which is a secure and popular method.&nbsp; The RSA <a href=\"http:\/\/teachcomputerscience.com\/algorithms\/\">algorithm<\/a> will generate a pair of public and private keys that are mathematically linked to each other.&nbsp; Public keys are used to encrypt data, and only the corresponding private key can be used to decrypt it.&nbsp; Even though the keys are paired together, neither can be derived from the other.&nbsp; In other words, even if you know a person\u2019s public key, you can\u2019t use that information to recreate his private key.<\/p>\n\n\n\n<p>Going back to our mailbox example, the mailbox location is the public key, something that is known to the public.&nbsp; The private key is with the owner of the mailbox, which is used to access the mailbox.<\/p>\n\n\n\n<p>Let\u2019s now take a look at how Users 1 and 2 can use asymmetric encryption to exchange messages securely.&nbsp; First of all, they exchange their public keys.&nbsp; User 1 gives his public key to User 2 and User 2 gives his public key to User 1.&nbsp; Now, User 1 can share his sensitive document again by taking the document and encrypting it with User 2\u2019s public key.&nbsp; He then sends the document to User 2, who uses his private key to decrypt the document and read it.&nbsp; Because they use asymmetric encryption, only User 2 can decrypt the message.&nbsp; Not even User 1, the creator of the message, can decrypt it, since he doesn\u2019t have User 2\u2019s private key.&nbsp; Users 1 and 2 have to keep their private keys well protected in order to maintain a strong and secure asymmetric encryption.&nbsp; If User 1\u2019s private key is stolen, it can be used to decrypt all messages that are sent to User 1.&nbsp; But the attacker cannot decrypt messages that were sent by User 1, because they can only be decrypted using User 2\u2019s private key.<\/p>\n\n\n\n<p>Asymmetric encryption is used in a lot of places where security really matters.&nbsp; You might not be aware of it, but every time you visit a website that has been secured via <a href=\"http:\/\/teachcomputerscience.com\/hypertext-transfer-protocol-http\/\">HTTPS<\/a>, you\u2019re actually using asymmetric encryption.&nbsp; It is also used to securely send emails with the PGP protocol. As one last example, Bitcoin uses asymmetric encryption to make sure that only the owner of a money wallet can withdraw or transfer money from it.<\/p>\n\n\n\n<h3 class=\"gb-headline gb-headline-39587718 gb-headline-text\"><strong>Further Readings:<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\"><li><a href=\"https:\/\/en.wikipedia.org\/wiki\/Public-key_cryptography\" target=\"_blank\" rel=\"noopener\">Public-key cryptography<\/a><\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Encryption is the process of taking a message and scrambling its contents so that only certain people can look at what\u2019s inside. In this article, we&#8217;re going to focus on asymmetric encryption. Two Types of Encryption Symmetric encryption Asymmetric encryption Asymmetric encryption was created to solve the problem brought about by Symmetric encryption.&nbsp; Let\u2019s look &#8230; <\/p>\n<p class=\"read-more-container\"><a title=\"Asymmetric Encryption\" class=\"read-more button\" href=\"https:\/\/teachcomputerscience.com\/asymmetric-encryption\/\" aria-label=\"More on Asymmetric Encryption\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_generate-full-width-content":"","_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[29],"tags":[204,47],"class_list":["post-2538","post","type-post","status-publish","format-standard","hentry","category-security","tag-article","tag-hide-old-upsell","generate-columns","tablet-grid-50","mobile-grid-100","grid-parent","grid-50"],"acf":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/posts\/2538","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/comments?post=2538"}],"version-history":[{"count":2,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/posts\/2538\/revisions"}],"predecessor-version":[{"id":605949,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/posts\/2538\/revisions\/605949"}],"wp:attachment":[{"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/media?parent=2538"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/categories?post=2538"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/tags?post=2538"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}