RSA

What is RSA RSA was developed by Ron Rivest, Adi Shamir, and Leonard Adleman in 1977. It is based on the assumption that factoring the product of two large prime numbers is computationally difficult. RSA Mechanism 1. Key Generation Choose two large prime numbers $p$ and $q$ Compute $n = p \times q$ Compute Euler’s totient $\phi(n) = (p - 1)(q - 1)$ Choose an integer $e$ such that $ 1 < e < \phi(n)$ and $gcd(e, \phi(n))=1$ Compute $d$ such that $ e \times d \equiv 1 (\mod \phi(n))$. The Public key is $(e, n)$ and the private key is $(d, n)$. 2. Encryption To encrypt a message $M$: $$ C = M^{e} \mod n $$ ...

August 4, 2025