{"id":20105,"date":"2022-11-26T13:56:16","date_gmt":"2022-11-26T13:56:16","guid":{"rendered":"https:\/\/mdr.foobrdigital.com\/?p=10282"},"modified":"2022-11-26T13:56:16","modified_gmt":"2022-11-26T13:56:16","slug":"rsa-cryptosystem","status":"publish","type":"post","link":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/2022\/11\/26\/rsa-cryptosystem\/","title":{"rendered":"RSA Cryptosystem"},"content":{"rendered":"\n<p>This cryptosystem is one the initial system. It remains most employed cryptosystem even today. The system was invented by three scholars&nbsp;<strong>Ron Rivest, Adi Shamir,<\/strong>&nbsp;and&nbsp;<strong>Len Adleman<\/strong>&nbsp;and hence, it is termed as RSA cryptosystem.<\/p>\n\n\n\n<p>We will see two aspects of the RSA cryptosystem, firstly generation of key pair and secondly encryption-decryption algorithms.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Generation of RSA Key Pair<\/h3>\n\n\n\n<p>Each person or a party who desires to participate in communication using encryption needs to generate a pair of keys, namely public key and private key. The process followed in the generation of keys is described below \u2212<\/p>\n\n\n\n<ul>\n<li><strong>Generate the RSA modulus (n)<\/strong>\n<ul>\n<li>Select two large primes, p and q.<\/li>\n\n\n\n<li>Calculate n=p*q. For strong unbreakable encryption, let n be a large number, typically a minimum of 512 bits.<\/li>\n<\/ul>\n\n\n\n<ul><\/ul>\n<\/li>\n\n\n\n<li><strong>Find Derived Number (e)<\/strong>\n<ul>\n<li>Number&nbsp;<strong>e<\/strong>&nbsp;must be greater than 1 and less than (p \u2212 1)(q \u2212 1).<\/li>\n\n\n\n<li>There must be no common factor for e and (p \u2212 1)(q \u2212 1) except for 1. In other words two numbers e and (p \u2013 1)(q \u2013 1) are coprime.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Form the public key<\/strong>\n<ul>\n<li>The pair of numbers (n, e) form the RSA public key and is made public.<\/li>\n\n\n\n<li>Interestingly, though n is part of the public key, difficulty in factorizing a large prime number ensures that attacker cannot find in finite time the two primes (p &amp; q) used to obtain n. This is strength of RSA.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Generate the private key<\/strong>\n<ul>\n<li>Private Key d is calculated from p, q, and e. For given n and e, there is unique number d.<\/li>\n\n\n\n<li>Number d is the inverse of e modulo (p &#8211; 1)(q \u2013 1). This means that d is the number less than (p &#8211; 1)(q &#8211; 1) such that when multiplied by e, it is equal to 1 modulo (p &#8211; 1)(q &#8211; 1).<\/li>\n\n\n\n<li>This relationship is written mathematically as follows \u2212<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-preformatted\">ed = 1 mod (p \u2212 1)(q \u2212 1)\n<\/pre>\n\n\n\n<p>The Extended Euclidean Algorithm takes p, q, and e as input and gives d as output.<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>This cryptosystem is one the initial system. It remains most employed cryptosystem even today. The system was invented by three scholars&nbsp;Ron Rivest, Adi Shamir,&nbsp;and&nbsp;Len Adleman&nbsp;and hence, it is termed as RSA cryptosystem. We will see two aspects of the RSA cryptosystem, firstly generation of key pair and secondly encryption-decryption algorithms. Generation of RSA Key Pair [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[495],"tags":[],"_links":{"self":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/20105"}],"collection":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/comments?post=20105"}],"version-history":[{"count":0,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/20105\/revisions"}],"wp:attachment":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/media?parent=20105"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/categories?post=20105"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/tags?post=20105"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}