RSA PROGRAM

# Decryption and e for encryption such that d e 1 mod

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decryption) and e (for encryption) such that d * e 1 (mod ø(n)) where ø(n) is the number of positive integers smaller than n that have no factor except 1 in common with n The integers n and e are made public, while p, q, and d are kept secret. Let m be the message to be sent, where m is a positive integer less than and relatively prime to n. A plaintext  message is easily converted to a number by using either the alphabet position of each letter (a=01, b=02, ..., z=26) or  using the standard ASCII table. If necessary (so that m<n), the message can be broken into several blocks.  The encoder computes and sends the number m' = m^e mod n To decode, we simply compute e^d mod n Now, since both n and e are public, the question arises: can we compute from them d? The answer: it is possible, if n   is factored into prime numbers. The security of RSA depends on the fact that it takes an impractical amount of time to factor large numbers two large prime numbers (a prime number

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