{"id":699,"date":"2021-01-17T05:38:10","date_gmt":"2021-01-16T18:04:32","guid":{"rendered":"https:\/\/exampracticetests.com\/ISC\/SSCP\/systems-security-certified-practitioner-sscp-question0691\/"},"modified":"2021-01-17T05:44:34","modified_gmt":"2021-01-17T05:44:34","slug":"systems-security-certified-practitioner-sscp-question0691","status":"publish","type":"post","link":"https:\/\/exampracticetests.com\/ISC\/SSCP\/systems-security-certified-practitioner-sscp-question0691\/","title":{"rendered":"Systems Security Certified Practitioner &#8211; SSCP &#8211; Question0691"},"content":{"rendered":"<div class=\"question\">The RSA Algorithm uses which mathematical concept as the basis of its encryption? <br \/><strong><br \/>A.<\/strong> Geometry<br \/><strong>B.<\/strong> 16-round ciphers<br \/><strong>C.<\/strong> PI (3.14159&#8230;) <br \/><strong>D.<\/strong> Two large prime numbers<\/div>\n<p><\/p>\n<style> .hidden-div{ display:none } <\/style>\n<p>\t\t\t\t\t\t\t<button onclick=\"getElementById('hidden-div').style.display = 'block'\"> Show Answer <\/button> <button onclick=\"getElementById('hidden-div').style.display = 'none'\">Hide Answer<\/button><\/p>\n<div class=\"hidden-div\" id=\"hidden-div\"><span style=\"\"><\/p>\n<div class=\"answer\">Correct Answer: <strong>D<\/strong><\/div>\n<p><strong>Explanation:<\/strong> <\/p>\n<div class=\"explanation\">\nSource: TIPTON, et. al, Official (ISC)2 Guide to the CISSP CBK, 2007 edition, page 254.<br \/>\nAnd from the RSA web site, <a href=\"http:\/\/www.rsa.com\/rsalabs\/node.asp?id=2214\" title=\"External link\" rel=\"nofollow noopener\" target=\"_blank\">http:\/\/www.rsa.com\/rsalabs\/node.asp?id=2214<\/a> : The RSA cryptosystem is a public-key cryptosystem that offers both encryption and digital signatures (authentication). Ronald Rivest, Adi Shamir, and Leonard Adleman developed the RSA system in 1977 [RSA78]; RSA stands for the first letter in each of its inventors&#8217; last names.<br \/>\nThe RSA algorithm works as follows: take two large primes, p and q, and compute their product n = pq; n is called the modulus. Choose a number, e, less than n and relatively prime to (p-1)(q-1), which means e and (p-1)(q-1) have no common factors except 1. Find another number d such that (ed -1) is divisible by (p-1)(q-1). The values e and d are called the public and private exponents, respectively. The public key is the pair (n, e); the private key is (n, d). The factors p and q may be destroyed or kept with the private key.<br \/>\nIt is currently difficult to obtain the private key d from the public key (n, e). However if one could factor n into p and q, then one could obtain the private key d. Thus the security of the RSA system is based on the assumption that factoring is difficult. The discovery of an easy method of factoring would &#8220;break&#8221; RSA (see Question 3.1.3 and Question 2.3.3).<br \/>\nHere is how the RSA system can be used for encryption and digital signatures (in practice, the actual use is slightly different; see Questions 3.1.7 and 3.1.8): Encryption<br \/>\nSuppose Alice wants to send a message m to Bob. Alice creates the ciphertext c by exponentiating: c = me mod n, where e and n are Bob&#8217;s public key. She sends c to Bob. To decrypt, Bob also exponentiates: m = cd mod n; the relationship between e and d ensures that Bob correctly recovers m. Since only Bob knows d, only Bob can decrypt this message.<br \/>\nDigital Signature Suppose Alice wants to send a message m to Bob in such a way that Bob is assured the message is both authentic, has not been tampered with, and from Alice. Alice creates a digital signature s by exponentiating: s = md mod n, where d and n are Alice&#8217;s private key. She sends m and s to Bob. To verify the signature, Bob exponentiates and checks that the message m is recovered: m = se mod n, where e and n are Alice&#8217;s public key.<br \/>\nThus encryption and authentication take place without any sharing of private keys: each person uses only another&#8217;s public key or their own private key. Anyone can send an encrypted message or verify a signed message, but only someone in possession of the correct private key can decrypt or sign a message.<\/div>\n<p><\/strong><\/span> <\/div>\n","protected":false},"excerpt":{"rendered":"<p>The RSA Algorithm uses which mathematical concept as the basis of its encryption? A. GeometryB. 16-round ciphersC. PI (3.14159&#8230;) D. Two large prime numbers Show Answer Hide Answer Correct Answer: D Explanation: Source: TIPTON, et. al, Official (ISC)2 Guide to the CISSP CBK, 2007 edition, page 254. And from the RSA web site, http:\/\/www.rsa.com\/rsalabs\/node.asp?id=2214 : [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[1078,694,3],"class_list":["post-699","post","type-post","status-publish","format-standard","hentry","category-systems-security-certified-practitioner-sscp","tag-choices","tag-question-0691","tag-systems-security-certified-practitioner-sscp"],"_links":{"self":[{"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/posts\/699","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/comments?post=699"}],"version-history":[{"count":1,"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/posts\/699\/revisions"}],"predecessor-version":[{"id":1775,"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/posts\/699\/revisions\/1775"}],"wp:attachment":[{"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/media?parent=699"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/categories?post=699"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/exampracticetests.com\/ISC\/SSCP\/wp-json\/wp\/v2\/tags?post=699"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}