Changes for page Programming knowledge

Last modified by Alexandru Pentilescu on 2025/07/09 14:25

From version 5.1
edited by Alexandru Pentilescu
on 2025/07/09 14:20
Change comment: There is no comment for this version
To version 6.1
edited by Alexandru Pentilescu
on 2025/07/09 14:25
Change comment: There is no comment for this version

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... ... @@ -114,5 +114,13 @@
114 114  
115 115  Let's assume Alice wishes to send Bob a message that only Bob knows how to decrypt. In order to do so, Bob must have previously made public his personal public RSA key, which consists of two numbers: a large modulus N and another number e such that
116 116  
117 -(m^^e^^)^^d^^≡ m (mod n).
117 +(m^^e^^)^^d^^≡ m (mod N) where m is the message.
118 +
119 +N and e must be public and not replaced or changed by malicious actors.
120 +
121 +Assuming that Alice has Bob's correct e and N public numbers, she can then send her own message m which is a number lesser than N by doing:
122 +
123 +m^^e^^ mod N = ciphertext
124 +
125 +Bob, on his side, will have precalculated N as the product of two very large primes p and q that he keeps secret. By using Carmichael's totient function on those numbers, he will calculate the missing d number that will allow him to transform the sent ciphertext back into its original m form using modular arithmetic.
118 118  )))